baikai-trace-otel 0.3.0.3 → 0.4.0.0

raw patch · 5 files changed

+2563/−87 lines, 5 filesdep ~baikaidep ~streamly-corePVP ok

version bump matches the API change (PVP)

Dependency ranges changed: baikai, streamly-core

API changes (from Hackage documentation)

Files

• CHANGELOG.md +2287/−0
• baikai-trace-otel.cabal +18/−15
• src/Baikai/Trace/Sink/OpenTelemetry.hs +62/−45
• test/Main.hs +163/−27
• test/PublicSurfaceSpec.hs +33/−0

@@ -0,0 +1,2287 @@+# Changelog++All notable changes to baikai are recorded here.++The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and+this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).++## [Unreleased]++## [baikai 0.6.0.0] - 2026-08-28++### Added++- `baikai`: `Baikai.ThinkingLevel.parseThinkingLevel :: Text -> Maybe+  ThinkingLevel` and `Baikai.Evidence.parseEvidenceStrength :: Text -> Maybe+  EvidenceStrength`, each beside its renderer. Three hand-copied tables — the+  evidence schema's level parser, `baikai-agent`'s KDL `effort` decoder, and its+  `--require-evidence` parser — now read them instead, so a level or strength+  added later cannot be added in one place and missed in three. (REV-2 G.6.)++- `baikai`: `Baikai.Agent.AgentRunResult` exports its selectors (`provider`,+  `exitCode`, `stdout`, `stderr`, `duration`). It exported neither them nor its+  constructor, so a consumer without generic-lens could not read a run's exit+  code at all. (REV-2 G.6.)++- `baikai`: `Baikai.Api.normaliseApi :: Api -> Api`, which collapses a `Custom`+  tag that spells a built-in API onto that constructor. The registry applies it+  to the key it stores and to the tag it is asked for, so a handler registered+  under `Custom "anthropic-messages"` answers a model tagged `AnthropicMessages`+  and the reverse; the two used to be separate entries and dispatch depended on+  which spelling the model happened to carry. Derived `Eq`/`Ord` on `Api` are+  deliberately unchanged: altering them would silently rearrange every+  `Map Api` a consumer holds. (REV-2 G.4.)++- `baikai`: `Baikai.Header`, a new module exporting `HeaderName` with+  `headerName` and `renderHeaderName`. See the `headers` retype under Changed.++- `baikai`: `Baikai.Error.ErrorCategory` gains `ContentFiltered` (wire tag+  `content_filtered`, never retryable) with the smart constructor+  `contentFiltered`. OpenAI's `finish_reason: "content_filter"` and Anthropic's+  `refusal` stop now carry it. Both used to be `OtherError`, so the only way to+  tell a filtered response from any other non-retryable failure was to match on+  the message text. __Breaking__ for a consumer whose `case` over+  `ErrorCategory` is exhaustive without a wildcard. (REV-1 1.7 residual.)++- `baikai` (breaking to construct, not to read): every record that can still+  grow a field is now built from an exported base value and refined by record+  update, and its constructor is no longer exported —+  `Baikai.Provider.Registry.ApiProvider` (`apiProvider` /`apiProviderWith`),+  `Baikai.Evidence.ModelCallEvidence` (`baseEvidence`),+  `Baikai.Evidence.EvidenceRequest` (`evidenceRequest`), `Baikai.Tool.Tool`+  (`mkTool`, with `emptyTool` kept for fixtures),+  `Baikai.Embedding.EmbeddingModel` (`emptyEmbeddingModel`),+  `Baikai.Cost.Log.CallLogConfig` (`callLogConfig`),+  `baikai-trace-otel`'s `OtelSinkOptions` (`defaultOtelSinkOptions`), and+  `baikai-agent`'s `AgentCliOptions` (`agentCliOptions`), `AgentCliRun`+  (`agentCliRun`), `AgentJob` (`agentJob`) and `AgentConfigPaths`+  (`emptyAgentConfigPaths`). Selectors, record update, `OverloadedRecordDot`+  reads and generic-lens labels all keep working; only construction from the+  constructor stops. Adding `describeThinking` to `ApiProvider` in 0.5.0.0 broke+  every third-party registration site, and `strengthCeiling` would have broken+  them again; from this release such an addition is a minor bump. (REV-2 G.1.)++- `baikai`: `Baikai.Provider.apiProvider`, which builds an `ApiProvider` from an+  `Api` tag and a streaming producer, deriving `complete` with+  `streamingComplete`; and `Baikai.Provider.Registry.apiProviderWith`, which+  takes the completer explicitly. Both default `describeThinking` to+  "nothing requested, nothing translated" and `strengthCeiling` to+  `EvidenceRequestedOnly`, matching `declaredStrength (Custom _)`.++- `baikai`: `Baikai.Tool.mkTool` — a tool from its name, description and JSON+  Schema. A tool built from `emptyTool` and sent unchanged reaches the wire with+  `input_schema: null`; `mkTool` has no such shape.++- `baikai`: `Baikai.Agent.AgentOutputFormat` (`TextFormat`, `JsonFormat`) with+  `renderAgentOutputFormat` and `parseAgentOutputFormat`, and+  `AgentRunRequest.outputFormat`, defaulting to `TextFormat`. `baikai-claude`+  renders `--output-format json` and `baikai-openai` renders `--json`, both+  right after the effort flags; `baikai-agent` reads it from+  `jobs.<name>.output-format`. This is the one setting an evidence record needs+  in order to observe a run's session, model and usage, and asking for it used+  to require the `provider-args` channel that an operator ceiling closes by+  default — an operator should not have to open a privileged channel to get a+  record. (REV-2 F.14.)++- `baikai`: `Baikai.Agent.AgentCeiling` gains three fields and the module gains+  the vocabulary they need. `allowedTools :: [Text]` names tool grants the+  operator permits beyond the ones `toolGrantsImpliedBy` (also new) says a+  capability implies on its own; `maxTimeout :: Maybe NominalDiffTime` and+  `maxOutputLimit :: Maybe Int` bound what any job may request, the second+  defaulting to the new `defaultMaxOutputLimit` (67108864, sixty-four+  mebibytes). `Baikai.Agent.ceilingViolations` is `applyAgentCeiling`'s violation+  list on its own, so a caller can concatenate it with violations of its own.+  (REV-2 F.3.)++- `baikai`: `Baikai.Content.toolArgumentsFromText` and+  `Baikai.Content.isCutOffToolCall`. The first is the single rule that turns a+  tool call's accumulated argument text into its `arguments` value — empty text+  is an empty object, non-empty text that does not decode is kept verbatim as a+  `String` — and both provider assemblers and core's stream-recovery path now+  use it, so the second means the same thing at every layer.++- `baikai`: new exposed module `Baikai.Provider.Internal.StreamWorker` — the+  bounded hand-off both HTTP providers now use between their SSE worker thread+  and the consumer draining the stream. `FrameQueue` is a 64-slot `TBQueue` plus+  a closed flag; `forkFrameWorker` closes the queue however the body ends, and+  `withFrameWorker` runs the consumer under `Stream.bracketIO` so the worker is+  killed when the stream stops. The module is exposed like+  `Baikai.Provider.Cli.Internal`, outside the PVP promise. See+  [docs/adr/0010](docs/adr/0010-a-stream-consumer-that-stops-owns-cancelling-the-producer.md).++- `baikai`: every Anthropic model in the generated catalog now carries an+  explicit `CompatAnthropicMessages` record stating the two request-shaping+  facts of its generation: `AnthropicMessagesCompat.thinkingStyle` (which+  extended-thinking wire shape it accepts) and the new+  `AnthropicMessagesCompat.supportsSamplingParameters` (whether it accepts+  `temperature`, `top_p` and `top_k`). Both are sourced from+  `baikai/data/models/anthropic.json`, which the fetcher writes from its+  curated `anthropicInclude` table, and `baikai-gen-models` now refuses an+  `anthropic-messages` entry that reaches it without a `compat` block rather+  than falling back to host auto-detection, which cannot know a generation.+  This is what fixes `claude-sonnet-5`, whose thinking requests were shaped by+  a prefix table that did not know the id. See+  [docs/adr/0009](docs/adr/0009-provider-capability-facts-live-in-the-generated-catalog-record.md).++- `baikai`: two new `Baikai.Evidence.ThinkingAdjustment` constructors,+  `SamplingDroppedUnsupportedModel` and `SamplingDroppedUnsupportedApi`, encoding as+  `{"kind":"sampling_dropped_unsupported_model","fields":["temperature","top_p"]}` and+  `{"kind":"sampling_dropped_unsupported_api","fields":["seed"]}`. They record sampling+  parameters removed because the model generation rejects them, or because the API has no+  such field on any generation. Both carry a `fields` array and no `requested` level, so+  they can appear on a call whose thinking mode is `absent`.++- `baikai`: `Baikai.Evidence.weakensThinking`, which says whether an adjustment weakens the+  thinking the caller asked for. Strict evidence mode filters through it, so a dropped+  sampling parameter is recorded without refusing the call — the documented contract is+  refusing a call that would weaken the requested *thinking level*.++- `baikai`: new exposed module `Baikai.Url` — the one place baikai turns a URL+  into a host name. `parseUrl` yields a `UrlParts` record with the scheme, host,+  port and path, plus flags saying whether userinfo, a query string or a+  fragment were present; it never holds their text, so the value cannot carry a+  secret into a log line. Alongside it: `urlHost`, `hostMatchesSuffix` (moved+  from `Baikai.Compat`, which now re-exports both), `renderEndpoint`,+  `stripApiVersion`, and `baseUrlProblem`, which says why a URL is unusable as a+  `Model.baseUrl` and what to do instead. See+  [docs/adr/0008](docs/adr/0008-one-url-host-parser-and-every-consumer-uses-it.md).++- `baikai`: new exposed module `Baikai.Provider.Transport.Classify` — the one+  rule every HTTP provider uses to classify a transport failure, exporting+  `classifyTransportException` plus the per-type functions it composes. The rule+  is *where* the failure happened, not what type it is: anything that breaks or+  ends the connection after the request went out is `TransientError`, anything+  that says the request or the configuration is wrong is not retryable, and a+  programming error stays `OtherError`. It understands all three shapes+  `http-client` can deliver — an `HttpException` of any constructor, a raw socket+  `IOException`, and a raw or wrapped `TLSException` — because the manager wraps+  the connect phase but not the body reader. Core gains direct `build-depends` on+  `http-types` and `tls`, both already in its install plan. Written for+  third-party `Custom` providers built on `http-client` as much as for baikai's+  own two. See+  [docs/adr/0011](docs/adr/0011-core-owns-transport-failure-classification.md).++- `baikai`: `Baikai.Error.parseHttpDate` and `Baikai.Error.retryAfterSecondsAt`.+  The first parses an HTTP-date in the IMF-fixdate form servers must send plus+  the two obsolete forms a recipient must accept; the second converts a+  `Retry-After` header in either of its forms to seconds against a reference+  instant, clamping a date already in the past to `0`.+  `parseRetryAfterSeconds` keeps its integer-only contract, now a deliberate+  division of labour rather than a limitation.++- `baikai`: new exposed module `Baikai.Http` — `canonicalBaseUrl`,+  `getClientEnvCached` and `cachedClientEnvCount`, the process-global+  `ClientEnv` cache that both HTTP provider packages now share instead of each+  keeping its own. Core gains direct `build-depends` on `servant-client`,+  `http-client` and `http-client-tls`, which were already in its install plan+  through the `openai` SDK.++- `baikai`: `Baikai.Evidence.ThinkingModeNotTranslated`, encoded as+  `"not_translated"`, and `Baikai.Evidence.untranslatedThinking`; and+  `Baikai.Evidence.Build.requestedTranslation`. A path where no adapter ran to+  translate the caller's level now records the level and says the translation is+  unknown, instead of saying nothing was asked. (REV-2 D.2.)++- `baikai`: `Baikai.Evidence.Build.missingEvidenceError`,+  `Baikai.Evidence.Build.strictnessOf` (moved here from `Baikai.Trace`, where it+  was private), `Baikai.Stream.requireEvidenceOnTerminal` and+  `Baikai.Provider.Registry.requireEvidenceOnResponse`. (REV-2 D.3.)++- `baikai`: `Baikai.Evidence.usageEnvelope`, and+  `Baikai.Evidence.Build.endpointIdentityAt`, `prepareEvidenceAt` and+  `minimalEvidenceAt`, which take the base URL the adapter actually resolved.+  The three unsuffixed functions remain and pass the model's own field.+  (REV-2 D.8, D.11.)++- `baikai`: `Baikai.Evidence.deriveStrength`, the single rule that turns an+  observed model, a provider request id and a response id into an+  `EvidenceStrength`. (REV-2 D.10.)++### Changed++- `baikai`: catalog refresh. `claude-opus-5` joins the curated Anthropic include+  set (adaptive thinking, sampling parameters rejected — the facts+  `docs/plans/60-make-anthropic-thinking-style-and-sampling-support-catalog-driven.md`+  said whoever curated it in would have to state), and the `gpt-5.6` family+  picks up its price cut: `gpt-5.6` and `gpt-5.6-sol` to $4.00/$20.00,+  `gpt-5.6-terra` to $2.00/$12.00, `gpt-5.6-luna` to $0.20/$1.20 per Mtok, cache+  rates in step. `Baikai.Models.Generated` gains `anthropic_claude_opus_5` and+  now carries 36 enabled models. No OpenAI id was added: the `gpt-5.6` family is+  still the newest one models.dev reports that speaks+  `openai-chat-completions`.++- `baikai` (breaking): `ResponseFormat`'s `JsonSchema` carries a+  `JsonSchemaFormat` record — `name`, `schema`, `strict`, exported+  selector-only with the base `jsonSchemaFormat name schema` — instead of+  holding the three fields directly. As fields of a sum they were partial+  selectors: `name f` on a `JsonObject` crashed at runtime rather than failing to+  typecheck, which contradicted the module's own documentation.+  `-Wno-partial-fields` is dropped from the module. The JSON encoding is+  deliberately unchanged (`{"tag":"JsonSchema","name":…,"schema":…,"strict":…}`)+  and is now pinned by a test, because `Options` derives `ToJSON` through it and+  at least one consumer keys a cache on the result. (REV-2 G.2.)++- `baikai`: `Baikai.Context.appendToolResult` returns its input context+  unchanged, and runs no dispatcher, when the response is error-shaped. A failed+  call has no assistant turn worth replaying and no tool calls to answer;+  appending its empty message put a turn into the transcript the model never+  took. `runToolLoop` has always stopped on such a response — the documented+  direct round trip in `docs/user/tools.md` reaches `appendToolResult` instead,+  and now behaves the same way. Its Haddock also stops claiming multi-call+  concurrency lives in the dispatcher: the calls are traversed in order.+  (REV-2 G.7.)++- Release metadata (REV-2 G.8): every publishable package now declares+  `tested-with: GHC ==9.12.4` and ships its `CHANGELOG.md` (a symlink to the+  root one, as `baikai` already did) via `extra-doc-files`, so Hackage shows a+  changelog and a tested compiler for all seven. `baikai-claude` and+  `baikai-openai` describe what they actually contain — four surfaces each, not+  "wraps package X" — and `baikai-trace-otel`'s `streamly-core` bound is+  `>=0.3 && <0.5`, matching every other package in the workspace rather than+  excluding the 0.4 series the others accept.++- `baikai` (breaking): `Options.headers` and `Model.headers` are keyed on+  `Baikai.Header.HeaderName` — a newtype over a case-insensitive `CI Text` that+  keeps the original spelling — instead of `Text`. A header name is+  case-insensitive on the wire, so a `Map Text Text` holding both+  `Authorization` and `authorization` sent whichever the assembling fold reached+  last; the map now holds one entry per header and the last write wins, as a+  caller writing two spellings would expect. `HeaderName` has an `IsString`+  instance, so `Map.singleton "x-test" "1"` and `#headers` updates keep+  compiling; the spelling given is what goes out on the wire and into JSON.+  (REV-2 G.5.)++- `baikai` (breaking): `Options.stopSequences` is `[Text]`, where empty means+  "send nothing", instead of `Maybe (Vector Text)` — `Nothing` and `Just []`+  were indistinguishable on the wire and only one of them could be right. Plan+  43's rule is lists for caller-side configuration and `Vector` for+  provider-bound sequences; this was the one field breaking it. `Options.seed`+  is `Maybe Int` rather than `Maybe Integer`: a seed is a machine integer at+  every provider that accepts one, and it now sits beside+  `timeoutMs :: Maybe Int`. (REV-2 G.5, R14.)++- `baikai` (breaking): `StopReason.Aborted` is removed. Nothing produced it —+  timeouts are `ErrorReason`/`TransientError`, and a consumer abort is recorded+  as evidence `CallAborted` — while `responseError`, `eventsFor` and+  `runToolLoop` all treated it as a *success*, so a value that reached any of+  them would have been silently mishandled. Since 0.6.0.0 a stream consumer that+  stops cancels the producer, so no consumer is left to receive such a terminal+  either. (REV-2 B.6.)++- `baikai`: dispatching a model whose `api` is still `emptyModel`'s+  `Custom ""` says so — `No provider registered for API: <blank Custom tag —+  emptyModel.api was never set>` — where the message used to end after the+  colon. `emptyModel`'s Haddock says the same thing. (REV-2 G.4.)++- `baikai`: `withTrace` and `withTraceStream` wait at most one second for the+  trace sink after writing the shutdown sentinel. On expiry the worker is+  abandoned — not killed, which would abort the sink's fold mid-step and lose+  its end-of-stream action — the call proceeds, and one stderr line reports+  `the trace sink did not confirm delivery within 1000 ms; its worker was+  abandoned, and events already queued may still be delivered later`. A sink+  that blocked forever used to hold the call forever and swallow the first+  attempt to cancel it. A caller under `EvidenceRequired` whose sink did not+  confirm delivery gets a failed call, through the same path a throwing sink+  takes; `Baikai.Evidence.Build.sinkFailureError` now says "its record was not+  confirmed written" rather than "not written", which is the honest claim for+  an abandoned worker whose events are still queued. The synthetic terminal a+  consumer's abort produces is delivered from a garbage-collection hook and is+  not guaranteed before process exit; that was always true and is now stated in+  `docs/user/model-call-evidence.md`, `docs/capabilities/call-tracing.md` and+  the `Baikai.Trace` module documentation, with the pattern for callers who need+  the record. See+  [docs/adr/0015](docs/adr/0015-trace-cleanup-is-bounded-and-abort-cleanup-is-gc-eventual.md).+  (REV-2 D.5, Theme 7.3.)++- `baikai`: `Baikai.Trace.Sink.multiSink` runs each member on its own drain+  thread behind its own unbounded channel, instead of folding `Fold.tee` across+  the list. `Fold.tee` runs one member then the other and lets either's+  exception escape, so a single throwing member stopped delivery to every+  sibling for the rest of the call and skipped their end-of-stream actions — an+  OpenTelemetry span paired with an unwritable file sink was opened and never+  ended, and nothing was exported. The step never blocks; the final action sends+  every member the sentinel, waits for every member, and reports one aggregate+  failure naming each failed member by zero-based index+  (`1 of 2 member sinks failed: member 0: …`). (REV-2 D.6.)++- `baikai`: `AgentSafety.allowedTools` is documented as the __grant__ it is.+  On Claude Code it renders `--allowedTools`, whose help reads "list of tool+  names to allow": it pre-approves tools the permission mode would otherwise+  raise a request for, and in an unattended run a request nobody answers is+  denied. The old Haddock called it "optional narrowing of the provider's tool+  set", which was the opposite, and `applyAgentCeiling` never looked at it. It+  is now bounded: a grant passes when the maximum capability implies it+  (`read-only` implies `Read`, `Glob`, `Grep`, `NotebookRead`, `TodoWrite`;+  `edit-workspace` adds `Edit`, `MultiEdit`, `Write`, `NotebookEdit`;+  `full-access` implies every grant) or when the operator named it in+  `policy.allowed-tools`. Matching is exact, so `Bash(git *)` is not `Bash`.+  A repository job that grants itself `Bash` under `edit-workspace` — which+  passed unexamined before — is now refused with exit 77 before any process is+  created. (REV-2 F.3.)++- `baikai` (breaking): `Baikai.Agent.CeilingViolation` gains five constructors:+  `ToolGrantForbidden`, `TimeoutExceeded`, `OutputLimitExceeded`,+  `RepositoryScopeForbidden` and `WorkingDirOutsideRepository`. A `case` over+  the type that was exhaustive is no longer.++- `baikai` (behaviour): the default ceiling has a finite `maxOutputLimit`, so+  `applyAgentCeiling defaultAgentCeiling` now refuses a request whose+  `outputLimit` is `Nothing` — capture without bound is exactly what the+  maximum exists to refuse. Jobs resolved through `baikai-agent` are unaffected:+  that layer's own default supplies a finite limit, and only an explicit+  `output-limit "unlimited"` reaches the ceiling as `Nothing`.++- `baikai`: a tool call cut off by the output cap is no longer executed.+  `runToolLoop` stops with the response and its tool calls intact when any call+  is cut off, and `appendToolResult` appends a `ToolResultMessage` with+  `isError = True` explaining why instead of calling the dispatcher. Previously+  both assemblers replaced truncated arguments with `{}` and a tool loop+  happily ran the call with no arguments at all. (REV-2 B.2.)++- `baikai`: `Baikai.Model.anthropicMessagesCompatFor` no longer overlays a+  thinking style guessed from the model id onto a model whose `compat` is+  `CompatNone`. `CompatNone` now means host auto-detection alone — the budget+  thinking shape, sampling parameters supported. Every catalog model carries an+  explicit record, so this changes nothing for them; a **hand-rolled** model+  naming an adaptive-era id (`claude-sonnet-5`, `claude-opus-4-7`,+  `claude-opus-4-8`, `claude-fable-5`) must now carry+  `CompatAnthropicMessages (defaultAnthropicMessagesCompat {thinkingStyle = AnthropicThinkingAdaptive, supportsSamplingParameters = False})`+  or start from the catalog value.++- `baikai`: `Baikai.Evidence.evidenceSchemaVersion` is now+  `baikai.model-call-evidence/1.1`. A minor bump: the two sampling adjustment kinds are a+  compatible addition, and no previously recorded digest changes.++- `baikai`: HTTP 413 classifies as `ContextOverflow` rather than `OtherError`,+  from the status alone and whatever the body says. 413 *is* the size-limit+  status and the caller's remedy — shrink the input — is the same either way;+  making the category depend on body wording would recreate for 413 the+  inconsistency this release fixes for connection resets. (REV-2 A.7.)++- `baikai`, `baikai-claude`, `baikai-openai`: an HTTP-date `Retry-After` is+  converted to seconds instead of ignored. Both transports use the response's own+  `Date` header as the reference instant, falling back to the local clock, so a+  CDN-fronted `429` — the common case for a date-valued `Retry-After` — now+  carries a hint rather than leaving the caller to guess. (REV-2 A.9.)++- `baikai`: **breaking.** `Baikai.Embedding.EmbeddingModel.apiKey` is now+  `Maybe ApiKeySource` rather than `ApiKeySource`. `Nothing` means the+  conventional environment variable for the model's host, from+  `defaultApiKeyEnvForBaseUrl` — the same table the chat providers use — and a+  host that table does not know refuses with an `AuthError` naming+  `EmbeddingModel.apiKey`. Migration: `apiKey = source` becomes+  `apiKey = Just source`. `EmbeddingModel` also derives `Eq` and `Generic`, so+  the `#field .~ value` idiom works on it as it does on every other record.+  (REV-2 E.3.)++- `baikai`: **breaking.** `AgentRunFailure`'s `RunTimedOut` constructor now+  carries a new record `AgentTimedOut` — the configured `limit` plus the+  `stdout` and `stderr` a timed-out run drained before its process group was+  killed — instead of a bare `NominalDiffTime`. A caller matching+  `RunTimedOut limit` becomes `RunTimedOut timedOut` and reads `timedOut ^.+  #limit`; `renderAgentRunFailure` is unchanged in what it says. The bytes were+  always there, drained from the moment the child was spawned, and were simply+  dropped on the timeout path — which is the run an operator most wants an+  account of, because the tool started, may have consumed tokens, and may+  already have changed the working tree.++- `baikai`: under `EvidenceRequired`, a successful terminal that carries no+  evidence record fails the call with `missingEvidenceError` rather than+  returning a silent success with zero `call_evidence` lines. Strict mode+  guaranteed that a record which was built and then lost fails the call; it did+  not guarantee that one was built. The rule is applied at both dispatch points,+  so `completeRequest` with no sink gets the same guarantee as a streaming call;+  a failed call keeps the provider's own error, and best effort is unchanged.+  See `docs/adr/0014-strict-evidence-means-a-record-exists.md`. (REV-2 D.3.)++- `baikai`: a caller's thinking level is recorded on every evidence path — the+  consumer abort, an unregistered provider, a `complete` handler that threw, and+  each provider's `immediateError`. The abort path asks the registered adapter's+  own `describeThinking`; the others record `not_translated`. All four used to+  record the caller's request as `absent`, which+  `docs/adr/0002-requested-translated-observed-are-never-collapsed.md` forbids.+  (REV-2 D.2.)++- **`baikai.model-call-evidence/2.0`.** Two digests cover different bytes, so a+  verifier must now select its rules by `schema_version`. `response_commitment`+  covers the provider-reported token counts and never baikai's computed cost:+  the cost comes from the caller's catalog rates rather than from the response,+  so the digest used to change whenever a price was edited and a verifier+  holding only the response could not recompute it. `request_configuration`+  summarises `output_config` and `response_format` as it already summarised+  `tools`, because a structured-output JSON schema carries author-written+  `description` strings and is content wherever it appears — the same schema was+  stripped from `tools[].input_schema` and survived verbatim through the other+  two keys. `thinking.mode` may also now be `"not_translated"`, which is a+  compatible addition. (REV-2 D.7, D.11.)++- **Breaking.** `baikai`: `Baikai.Provider.Registry.ApiProvider` gains a fifth+  field, `strengthCeiling :: EvidenceStrength`, and+  `Baikai.Evidence.Build.checkEvidenceRequirements` takes that ceiling where it+  took an `Api`. The gate compared against `declaredStrength`, a table keyed by+  the API tag, which necessarily answered `EvidenceRequestedOnly` for every+  `Custom` transport — so a gateway that genuinely observes a model could never+  satisfy a strict caller who required that it did. Only a provider knows what+  its evidence reaches. `EvidenceRequestedOnly` reproduces the old behaviour for+  any custom provider; the four built-in providers fill the field from+  `declaredStrength`, which is unchanged in value and still used by the+  unattended-agent surface. (REV-2 D.10, G.1.)++- `baikai`, `baikai-claude`, `baikai-openai`: one strength derivation replaces+  three. An observed **response id** now counts as correlation alongside a+  captured request-id header, so a host that names its model and its response id+  on every chunk but sends no header reaches `model_observed` instead of+  `requested_only` — which had put it *below* a host that sent only a header and+  named nothing. `anthropicStrength` and `openaiStrength` are removed;+  `Baikai.Provider.Cli.Internal.subprocessStrength` keeps its signature and+  delegates. (REV-2 D.10.)++### Removed++- `baikai` **0.6.0.0** (breaking): the sixteen `_Type` base-value aliases deprecated in+  0.3.0.0 — `_Options`, `_Context`, `_Model`, `_ModelCost`, `_Response`,+  `_Usage`, `_Cost`, `_CostBreakdown`, `_Tool`, `_TextContent`,+  `_ThinkingContent`, `_ToolCall`, `_ImageContent`, `_EmbeddingModel`,+  `_InteractiveLaunchRequest` and `_InteractiveLaunchResult`. Each has an+  `empty…` or `zero…` replacement of the same value, named in the pragma that+  has been on it since 0.3.0.0. The 0.3.0.0 entry said they remained "for this+  release"; 0.4.0.0 and 0.5.0.0 shipped without removing them because no entry+  named a version.+  `docs/adr/0016-deprecated-names-are-removed-at-the-next-major.md` now fixes+  the rule: a name deprecated in `A.B.0.0` is removed in `A.(B+1).0.0`, and+  every pragma says so. (REV-2 G.3.)++- `baikai` **0.6.0.0** (breaking): `Baikai.Trace.newEventId`. It has delegated to+  `Baikai.Evidence.newCallId` since 0.5.0.0; call that. (REV-2 G.3.)++- `baikai` **0.6.0.0** (breaking): `Baikai.Compat.defaultAnthropicThinkingStyle`, deprecated+  earlier in this cycle. Nothing in baikai consults it — the thinking style of a+  first-party Anthropic model is a field of its generated catalog record+  (`Baikai.Models.Generated`); start from that value, or set+  `CompatAnthropicMessages` explicitly.++- `baikai` (breaking): `AgentRunRequest.envPassthrough` is renamed `envRequires`.+  The field is a list of variables the job declares it requires, checked as a+  precondition; it has never passed anything through, and the KDL key has said+  `env-requires` since the setting existed.++- `baikai` (breaking): `AgentRunFailure.OutputMalformed`, and with it+  `baikai-agent`'s exit code 70 and its `internalExitCode` export. Nothing ever+  constructed the constructor, and giving it a producer would have been wrong:+  the runner treats the tool's output as best-effort observation and its+  deliverable is the changed working tree, so a run that edited files correctly+  and then printed an unparseable final line would have been reported as a+  failure with its exit code and output discarded. A record's `strength` and+  `unobserved` fields already say when output could not be read. (REV-2 F.13.)++### Fixed++- `baikai`: the terminal event and its evidence record are pushed to the trace+  sink exactly once under asynchronous exceptions. The terminal path pushed the+  evidence record, pushed the terminal event and only then set the+  already-sent flag; an exception delivered between the last two made the+  stream finaliser read the flag as unset and push a second `CallEvidence` and+  an `aborted` `CallFailed` after the real `CallFinished`, so a sink saw two+  records and two contradictory terminals for one call. All three writes now+  run inside one `uninterruptibleMask_` with the flag first. (REV-2 D.4.)++- `baikai`: `Baikai.Cost.Log.closeCallLog` is idempotent. The first caller+  claims the handle and waits for the worker; a second returns at once instead+  of blocking forever on an `MVar` the worker had already emptied — a shape+  `withCallLog` makes easy to reach, since its bracket closes a handle the body+  may also have closed. An `appendEntry` after the close enqueues nothing.++- `baikai`: `reassembleResponse` is total under duplicated, late and+  timestamp-less input. The first `EventStart` wins the skeleton and+  `responseId` merges with `<|>`, so a later `Nothing` cannot erase an id an+  earlier event supplied; events after the first terminal are ignored, so a+  producer that keeps talking cannot rewrite the answer; and `latencyMs` falls+  back to the reassembler's own wall clock when neither the skeleton nor the+  terminal carries a provider timestamp, instead of reporting a zero that reads+  as "instant". (REV-2 B.7.)++- `baikai`: an `EmbeddingModel` pointed at a non-OpenAI host no longer sends+  `OPENAI_API_KEY` to it. The default key source was that variable whatever the+  base URL said, so pointing the client at DeepSeek handed DeepSeek an OpenAI+  credential. It now resolves per host, and refuses an unknown one. New+  `resolveEmbeddingKey` and `embeddingClientEnv` expose both decisions without+  making a request. (REV-2 E.3.)++- `baikai`: `Baikai.Embedding.embed` no longer allocates a TLS manager per call.+  It used the `openai` SDK's own `getClientEnv`, which builds a fresh manager+  every time; it now takes one from `Baikai.Http`'s process-global cache, the+  same one the chat providers use, so an embedding call and a chat call to one+  host share a connection pool.++- `baikai`: **a credential in a header is no longer printed.** `Options.headers`+  and `Model.headers` went through derived `Show` and `ToJSON` instances that+  rendered every value verbatim — while `Baikai.Options`' own documentation+  invites callers to put a gateway's `Authorization` header there and the+  getting-started guide tells them to `print resp`, which renders the embedded+  `Model`. Both types now have hand-written instances that render exactly what+  the derived ones did, except that the value of a header whose name looks+  credential-carrying (`authorization`, `api-key`, `apikey`, `token`, `secret`,+  `cookie`, `password`, or any name ending in `-key`, case-insensitively) prints+  as `<redacted>`. `Baikai.Auth` exports the three pieces — `redactedMarker`,+  `isCredentialHeader`, `redactHeaderValues` — so a caller can apply the same+  rule to its own logging. Only the rendering changes: the field is untouched,+  `Eq` is untouched, and the header is still sent as written. A JSON round trip+  of a `Model` is deliberately lossy, since a serialised `Model` is exactly the+  thing that should not carry a key. (REV-2 E.2.)++- `baikai`: an API-key environment variable set to the empty string, or to+  nothing but whitespace, now counts as **unset**. `ApiKeyEnv` fails with an+  `AuthError` naming the variable and saying it is not set or is empty;+  `ApiKeyEnvChain` skips it and continues, and reports every name when none+  yields a key. Previously an empty variable resolved to an empty key, which+  short-circuited a chain and produced `Authorization: Bearer ` and a provider+  401 that said nothing about the cause. A key with real content is still passed+  through untrimmed. (REV-2 E.6.)++- `baikai`: **the host parse no longer lets a base URL choose which key baikai+  sends.** `urlHost` took the text after the *last* `@` anywhere in a URL, so+  `https://proxy.example.com/v1?u=@api.openai.com` named the host+  `api.openai.com`: `defaultApiKeyEnvForBaseUrl` resolved `OPENAI_API_KEY`,+  `autoDetectOpenAICompletions` returned OpenAI's own compatibility record, and+  the bearer token went to `proxy.example.com`. Anyone who could set `baseUrl` —+  a `Model` decoded from JSON, a proxy override — could pick which provider's+  credential to be handed. The same defect broke the benign direction:+  `https://api.openai.com/v1/@x` named the host `x` and resolved no key at all.+  The authority now ends at the first `/`, `?` or `#`, and userinfo is only ever+  the last `@` inside it. (REV-2 A.1 / E.1.)++- `baikai`: `Baikai.Evidence.Build.sanitizeEndpoint` was a second, separately+  written parser that bounded the authority at the first `/` only, so a URL with+  a query and no path recorded the wrong host. It is now `renderEndpoint <$>+  parseUrl`, which also means a recorded endpoint has a lower-cased scheme and+  host; the path keeps its case and trailing slash.++- `baikai`: `parseCodexJsonlStream` assembles lines in **linear time**. It+  previously unpacked every chunk into a stream of bytes and appended them one+  at a time with `BS.snoc`, copying the whole accumulator per byte — quadratic+  in line length, so one codex event carrying a two-million-character message+  cost on the order of a trillion byte moves and in practice never finished.+  Lines are now cut out of each chunk with `BS.elemIndex` and `BS.splitAt`, and+  the pieces of a line that spans a chunk boundary are joined once. Behaviour is+  unchanged: a non-JSON line is still skipped, and a last line without a+  trailing newline is still parsed.++- `baikai`: a Codex custom agent's instructions body renders as a TOML+  **literal** multi-line string (`'''`), which interprets nothing, instead of a+  basic one (`"""`), which interprets backslash escapes. As a basic string an+  instruction as ordinary as "match `\d+`" made Codex refuse to load the file;+  `tomllib` rejects the old output with `Unescaped '\' in a string`. A body a+  literal string cannot hold — one containing three apostrophes, a bare carriage+  return, or a control character other than tab and newline — falls back to a+  fully escaped basic string. `tomlString`, which renders `name` and+  `description`, now escapes every control character as TOML 1.0 requires+  instead of only the five it happened to name.++- Documentation: `baikai`'s Haddock no longer describes behaviour the code left+  behind. The trace event's token counts are `Maybe` because a non-assistant+  terminal has no usage, not because the CLI providers report nothing — since+  0.5.0.0 both carry what the tool reported. `EventStart`'s `partial` is a+  message skeleton with empty content, zero usage and no stop reason; the api,+  provider and model id live on the `Response`. A lifted stream's `EventStart`+  carries the final usage and stop reason already filled in, because the+  response is complete before the stream begins. `Baikai.CacheRetention` no+  longer mentions an OpenAI Responses 24-hour bucket no code emits. System+  prompts are documented as living on `Context.systemPrompt` rather than on a+  `Baikai.Request` module that no longer exists, `emptyModel`'s `compat` is+  described as auto-detection rather than a placeholder, tool dispatch says+  calls run one at a time in order, and every reference to a plan number is+  gone. (REV-2 H.4.)++## [baikai-claude 0.6.0.0] - 2026-08-28++### Added++- `baikai-claude`: `Baikai.Provider.Claude.Internal.Request` exports `planRequest`,+  `SamplingPlan`, `uncappedMaxTokensFloor` and `normalizeToolCallId` as test seams.+  `planThinking` and `describeThinkingFor` are now projections of `planRequest`, so the+  strict gate, the request builder and the evidence record read one answer.++### Changed++- `baikai-claude`, `baikai-openai` (breaking): each provider's streaming+  machinery moved from `Baikai.Provider.<P>.Api` to+  `Baikai.Provider.<P>.Internal.Stream` — the `SseDriver` seam, `liveSseDriver`,+  `<p>StreamWith`, `Assembler`, `emptyAssembler`, `translate`, and on the OpenAI+  side `RawChunk`, `RawToolDelta`, `parseChunk`, `parseFrame`, `TagScanState`,+  `scanThinkTags`, `closeOpenStream`, `RawUsage`, `parseUsage` and+  `rawUsageToUsage`. `Api` now exports exactly `register`, the provider value+  and the live stream function. The `.Internal` module is exposed for the test+  suites and sibling packages and, like every `.Internal` module, may change in+  any release without a major bump — so changing the assembler stops being a+  documented break. `Shape`, `Sse` and `Transport` keep their names and gain the+  same no-guarantees header. `_TagScanState` is renamed `emptyTagScanState`.+  (REV-2 G.1.)++- `baikai-claude`, `baikai-openai`: a consumer that stops reading now stops the+  provider. Both packages fork their SSE worker under `Stream.bracketIO` and+  hand frames through the bounded `FrameQueue` above instead of an unbounded+  `Chan`. A consumer that cancels — `Ctrl-C`, `System.Timeout.timeout`,+  `cancel` — releases the HTTP connection immediately; a consumer that abandons+  the stream (`Stream.take 3`) stops the socket read within 64 further frames+  and releases the connection at the next major garbage collection. Previously+  the worker read the entire generation into memory for a consumer that would+  never look at it, and the provider billed all of it. The three cleanup+  strengths are stated in+  [docs/adr/0010](docs/adr/0010-a-stream-consumer-that-stops-owns-cancelling-the-producer.md)+  and in caller terms in `docs/user/streaming.md`.++- `baikai-claude`: `anthropic_claude_sonnet_4_6` now sends the adaptive+  thinking shape rather than `budget_tokens`. The budget shape is deprecated+  for that generation; baikai sends the shape Anthropic documents as current.++- `baikai-claude`, `baikai-openai`: **behaviour change.** `Options.timeoutMs` of+  `Just n` with `n <= 0` is refused as `InvalidRequest` before the action runs, so+  no connection is opened. `System.Timeout.timeout` returns immediately at zero+  and runs unbounded below it, and the previous `max 0` clamp made both spellings+  fail instantly as a *retryable* `TransientError` — a classification a caller's+  retry loop re-issues forever for what is a configuration mistake. `Nothing`+  remains the only spelling of "no bound". (REV-2 A.10.)++- `baikai-claude`, `baikai-openai`: an evidence record's `endpoint` names the+  host the call actually went to. Both adapters substitute a vendor default for+  an empty `Model.baseUrl` inside `prepareCall`, so a call with a perfectly+  definite destination recorded `endpoint: null`. Where no adapter ran, `null`+  remains the truthful answer. (REV-2 D.8.)++- `baikai-claude`: the `claude` dependency moves from `^>=1.4` to `^>=1.5`.+  1.5.0 adds a `Pause_Turn` constructor to `Claude.V1.Messages.StopReason`, and+  `mapStopReason` matches that type with no wildcard under+  `-Werror=incomplete-patterns`, so the bump forced a decision. A paused turn+  maps to `Stop`: Anthropic suspends the turn mid-flight for a long-running+  server-side tool and expects the caller to send the message back to continue+  it, so nothing failed, and `Baikai.StopReason` has no constructor that says+  "resume me". Widening that public sum is a breaking change for every consumer+  who matches on it exhaustively, and it is not this bump's to make. The general+  rule is+  [ADR 0018](docs/adr/0018-a-provider-stop-reason-with-no-baikai-equivalent-maps-to-the-nearest-truthful-one.md):+  a provider stop reason with no baikai equivalent maps to the constructor that+  is truthful about whether the call failed, and the sum widens only when baikai+  would behave differently for it.++- `baikai-claude`: `Messages.StreamUsage` lost its `Generic` instance in `claude`+  1.5.0, so the `message_delta` usage is read through `OverloadedRecordDot`+  rather than a generic-lens label. `Messages.max_tokens` and+  `Messages.output_config` became ambiguous selectors — `Messages.Fallback`+  carries both names — so the provider's tests read them through `^. #max_tokens`+  and `^. #output_config` instead.++### Removed++- `baikai-claude`, `baikai-openai` **0.6.0.0** (breaking): the eight registration shims —+  `registerWith`, `registerWithRegistry` and `registerWithRegistryAndConfig` in+  both `Cli` modules, and `registerWithRegistry` in both `Api` modules. Register+  the exported provider value instead:+  `registerApiProvider (claudeCliProvider cfg)`,+  `registerApiProviderWith reg (codexCliProvider cfg)`,+  `registerApiProviderWith reg claudeMessagesProvider`. The batch-mode note that+  had accumulated on `registerWith` — why `complete` stays on the direct path+  rather than going through `streamingComplete` — moves to the provider value it+  describes. (REV-2 G.3.)++- `baikai-claude`, `baikai-openai`: `responseToError` and `classifyErrorText`+  (and its private `classifySdkHttpText` half) from both+  `.Internal.ErrorClass` modules. Neither package runs a `servant-client` client+  on the chat path any more, so the `ClientError` branch was unreachable, and the+  text classifiers parsed a string shape the local SSE transports stopped+  producing in July. The phrase table `classifyErrorText` held survives as the+  message fallback inside `classifyErrorFrame`, pinned through the entry point the+  runtime actually uses. Both modules are documented as outside the PVP-stable+  surface, so this is not a major bump; version bumps are recorded once, later.++- **Breaking.** `baikai-claude`: `Baikai.Provider.Claude.Api.anthropicStrength`+  and `baikai-openai`: `Baikai.Provider.OpenAI.Api.openaiStrength`, both replaced+  by `Baikai.Evidence.deriveStrength`.++### Fixed++- `baikai-claude`, `baikai-openai`: a failure that lands while the response body+  is streaming is classified as the transient failure it is. A connection reset,+  a server closing the socket mid-chunk, a body shorter than its declared length+  and a TLS session torn down after the handshake all now terminate the stream+  with `TransientError` and `isRetryable = True`, carrying whatever text had+  already been drained. Every one of them used to be `OtherError` with+  `isRetryable = False`, while the identical failure at connect time was+  transient — because `http-client` wraps the connect phase with the manager's+  exception wrapper and the body reader with nothing that converts a socket+  `IOException` or a `TLSException`, so those reached the worker raw and missed+  the `HttpException` branch entirely. (REV-2 A.2.)++- `baikai-claude`, `baikai-openai`: a transport failure mid-stream now closes+  the blocks that were open when it arrived, on both providers, so a consumer+  reading raw events and a consumer reassembling them see the same partial+  output. Both providers built their terminal from the closed blocks alone and+  silently dropped open text, thinking and tool arguments. On the Claude side+  this covers `translate (Left …)`, the in-band `error` frame, and the+  unexpected end of stream. (REV-2 B.3.)++- `baikai-claude`: an SSE frame whose event `type` — or whose+  `content_block_delta` `delta.type` — the SDK has no constructor for is now+  skipped instead of ending the stream with a decode error. The SDK decodes both+  with no unknown-tag fallback, so a new frame type from Anthropic used to be a+  terminal fault. A frame of a *known* type that still fails to decode remains+  one. `Baikai.Provider.Claude.Sse` exports the new `decodeFrame`. (REV-2 B.5.)++- `baikai-claude`, `baikai-openai`: an empty `data:` heartbeat is ignored, and+  on the OpenAI side `[DONE]` is compared after trailing whitespace is trimmed,+  so `data: [DONE] ` and `data: [DONE]\r` end the stream rather than failing to+  decode. (REV-2 A.8.)++- `baikai-claude`: every failing stream now begins with `EventStart`. The+  producer pre-seeds the start event before the first wire read, exactly as the+  OpenAI producer already did, and `message_start` updates the assembler without+  emitting a second one. Previously a 401, a rate limit, an in-band `error`+  frame or an EOF arriving before `message_start` produced a lone `EventError`,+  breaking the protocol `Baikai.Stream.Event` documents. `StartPayload.responseId`+  is consequently `Nothing` on both HTTP providers; the provider's message id+  rides `TerminalPayload.responseId`, which `reassembleResponse` already prefers.+  (REV-2 A.4, REV-1 Theme 1.1.)++- `baikai-claude`, `baikai-openai`: an asynchronous exception delivered to the+  stream worker can no longer strand its consumer. End-of-frames is a flag set+  by the worker fork's own `finally` rather than a sentinel value pushed onto+  the channel, so a worker that dies without running its normal exit path still+  ends the stream in an `EventError`. Previously the consumer blocked until the+  runtime's deadlock detector noticed.++- `baikai-smoke`: two keyed cases against `claude-sonnet-5` — one asking for+  thinking (which is a 400 before this release) and one setting `temperature` — plus+  `deepseek-chat` and `openrouter/openai/gpt-4o-mini` in `apiCases`, so the tool and+  structured-output smokes run against a compatible host that is not OpenAI.+  `CompatSmoke` now asserts DeepSeek honoured the output cap rather than only that it+  answered, and `CacheSmoke` asserts the cached token classes cost something.++- `baikai-claude`: a thinking request on `claude-sonnet-5` no longer 400s. It sends+  `"thinking":{"type":"adaptive"}` and no `budget_tokens`, because the shape is read off+  the model's catalog record rather than guessed from its id. (REV-2 C.1.)++- `baikai-claude`: `temperature` and `top_p` are no longer sent to a model generation that+  rejects them with a 400. They are omitted and the omission is recorded as+  `sampling_dropped_unsupported_model` in the call's evidence. `seed`, `frequencyPenalty`+  and `presencePenalty`, which the Anthropic Messages API has no field for on any+  generation, are recorded as `sampling_dropped_unsupported_api`. (REV-2 C.1, C.5.)++- `baikai-claude`: a model whose `maxOutputTokens` is `0` no longer sends+  `"max_tokens":0`, which Anthropic rejects — and, with thinking set, no longer had its+  whole thinking plan discarded for not fitting inside a ceiling of zero. It sends+  `uncappedMaxTokensFloor` (1024, the SDK's own default) instead. An explicit+  `maxTokens = Just 0` is still forwarded as written. (REV-2 C.2.)++- `baikai-claude`: replay no longer sends an empty text block or an empty `content` array,+  both of which Anthropic rejects. An empty text block is dropped; an assistant turn left+  with nothing is dropped whole (it is baikai's own artifact — a block that closed with no+  deltas, or only unsigned thinking, which replay already omits); a user turn left with+  nothing is refused locally with a message naming the turn. (REV-2 C.3.)++- `baikai-claude`: tool-call ids that differ only in characters the alphabet forbids, or+  only past character 64, no longer normalise onto the same id and misroute a tool result.+  A conforming id passes through unchanged — every id Anthropic and OpenAI actually mint+  does — and any other is truncated to 51 characters and suffixed with twelve hex+  characters of its SHA-256. Two `tool_use` blocks in one turn that still collide are+  refused rather than sent. (REV-2 C.7.)++- Documentation: `baikai-claude`'s and `baikai-openai`'s Haddock point at the+  functions that exist. `Baikai.Compat` named+  `Baikai.Provider.OpenAI.Api.mkOpenAIResponseFormat`,+  `…Api.applyThinkingFormat` and `…Api.translateTextLikeDelta`; the first two+  moved to `…Internal.Request` and the third is+  `…Internal.Stream.scanThinkTags`. `ThinkingFormat`'s note said the six+  non-native shapes all clamp through `compatibleEffort`; three do, Z.ai and+  Qwen send a bare toggle, and `ThinkingFormatNone` drops the control.+  `immediateError` carried two `-- |` headers where one was intended.+  (REV-2 H.4.)++- `baikai-claude`: an Anthropic call reports its thinking tokens. `Usage.reasoningTokens`+  was hard-coded to `Nothing` on this provider because `claude` 1.4.0's+  `Messages.Usage` had no breakdown to read; 1.5.0 adds+  `output_tokens_details.thinking_tokens`, and both `message_start` and+  `message_delta` now fill the field from it. `reasoningTokens` is an+  informational subset of `outputTokens`, so no total and no cost moves.++- `baikai-claude`: the prompt-side token counts survive a server-side tool run.+  The final `message_delta` used to contribute only `output_tokens`, and+  `inputTokens`, `cacheReadTokens` and `cacheWriteTokens` kept whatever+  `message_start` had reported — which is wrong for a call whose prompt grew+  mid-stream. `claude` 1.5.0 exposes those three on `Messages.StreamUsage`, and+  each is now taken when present. An absent field still keeps the+  `message_start` figure rather than zeroing it, so a model that sends only+  `output_tokens` is accounted for exactly as before.++## [baikai-openai 0.6.0.0] - 2026-08-28++### Added++- `baikai-openai`: `Baikai.Provider.OpenAI.Internal.ErrorClass.classifyErrorFrame`+  and `Baikai.Provider.OpenAI.Api.parseFrame`, which sort a decoded SSE payload+  into a classified in-band error or a completion chunk.++### Changed++- `baikai-openai`: **breaking.** `Baikai.Provider.OpenAI.Shape`'s+  `injectThinkingShape`, `describeThinkingShape`, `shapeRequestBody` and+  `streamRequestBody` take a `Bool` after the compat record — whether the model+  advertises reasoning support (`Model.reasoning`). A level on a `reasoning = False`+  model now sends no `reasoning_effort`, `reasoning`, `thinking` or `enable_thinking`+  key on any host, and records `thinking_dropped_unsupported_model` instead. The model+  check runs before the host-format check. This is what stops `gpt-4o-mini` plus a+  level from 400ing. (REV-2 C.4.)++### Fixed++- `baikai-openai`: an in-band `{"error": …}` frame on a `2xx` stream terminates+  the call with the frame's own classification, status and message. Compatible+  hosts (OpenRouter, DeepSeek, Together) report an upstream failure they only+  learned about after committing to a `200` this way, and `parseChunk` never+  looked at `error`. The pre-fix behaviour was worse than a bad category:+  OpenRouter's frame carries `choices[0].finish_reason = "error"`, which mapped+  to `Stop`, so the call ended as `EventDone` with `errorInfo = Nothing` — a+  consumer switching on the terminal saw a *completed* call. A frame with no+  `choices` beside the error ended as+  `OtherError "openai stream ended without finish_reason"`. (REV-2 A.3.)++- `baikai-openai`: reasoning that arrives after visible text closes the open+  text block before opening the thinking block, so at most one of the two is+  open at a time, every `_End` precedes the next `_Start`, and no `contentIndex`+  is revisited after a later one. (REV-2 B.4.)++- `baikai-openai`, `baikai-claude`: **a provider POST no longer follows+  redirects.** `http-client`'s default is to follow up to ten with every header+  intact, so a 3xx would have re-sent the bearer token (or `x-api-key`) to+  whatever host the `Location` header named. `redirectCount` is now zero and the+  3xx is delivered as the one in-band terminal error carrying its status. Each+  transport's request builder is exported as `buildRequest`, so the method, the+  composed path and the redirect policy are assertable without a connection.+  (REV-2 A.5 / E.4.)++- `baikai-openai`, `baikai-claude`, `baikai`: **the base-URL convention is+  stated and enforced.** `Model.baseUrl` and `EmbeddingModel.baseUrl` are the+  API *root* — the host, or the prefix a host mounts the API under — because+  baikai appends `/v1/chat/completions`, `/v1/messages` or `/v1/embeddings`+  itself. A trailing `/v1` is accepted and removed rather than doubled, so+  `https://api.deepseek.com/v1` now requests `/v1/chat/completions` instead of+  `/v1/v1/chat/completions`. A base URL with no scheme, a scheme other than+  `http`/`https`, credentials, a query string, a fragment, or a path that is+  already an endpoint is refused as an `InvalidRequest` naming the problem —+  and refused *before* a key is read, so an unusable base URL never causes a+  credential to be looked up. The message renders the URL without its userinfo+  or query, so it is safe to log. `docs/user/models-and-providers.md` gains a+  **Base URLs** section stating all of it. (REV-2 A.6.)++- `baikai-openai`, `baikai-claude`: the `ClientEnv` cache was duplicated in each+  package and keyed on the raw base-URL text, so `https://h` and `https://h/`+  were two TLS managers and two connection pools to one host. There is now one+  cache, in `Baikai.Http`, keyed on the canonical rendering of the parsed base+  URL. `Transport.getClientEnvCached` and `Transport.cachedClientEnvCount` are+  re-exports of the core functions and keep their signatures.++- `baikai-openai`: the Codex interactive launcher now **refuses the two approval+  policies the installed CLI rejects**. `codex --help` at `codex-cli 0.149.1`+  lists exactly `on-request` and `never` for `--ask-for-approval`;+  `CodexApprovalUntrusted` and `CodexApprovalOnFailure` are older spellings the+  CLI answers with `error: invalid value 'untrusted' for+  '--ask-for-approval'`. Rendering them made a launch return `Right` carrying a+  non-zero exit code — a session that ran and failed — instead of the `Left+  SafetyNotExpressible` this module promises for a policy that cannot be+  honoured. They are refused before any process is created, and refused rather+  than quietly mapped onto `on-request`, because substituting a different+  approval policy would change what the caller asked for. The constructors and+  their spellings are unchanged, so code that matches on `CodexApprovalPolicy`+  keeps compiling.++## [baikai-trace-otel 0.4.0.0] - 2026-08-28++### Added++- `baikai-trace-otel`: `OtelSinkOptions` derives `Generic`, so `#spanName`+  resolves on it. No `Eq` or `Show`: `OpenTelemetry.Context.Context` has neither,+  and an instance that ignored `parentContext` would be a lie. (REV-2 G.6.)++- `baikai-trace-otel`: `OtelSinkOptions.parentContext :: Maybe Context`, default+  `Nothing`. When set, every span the sink opens becomes a child of the span in+  that context instead of a root, so a call can be nested under the caller's own+  request span. It is a value fixed when the sink is built rather than an action+  run per call, because the fold runs on baikai's trace worker thread where the+  caller's thread-local context is invisible: capture the context on your own+  thread (`ctx <- getContext`, or `Context.insertSpan mySpan Context.empty`) and+  build the sink for that request. __Breaking for positional construction__ of+  `OtelSinkOptions`; the documented path is a record update on+  `defaultOtelSinkOptions`. (REV-2 D.9.)++### Changed++- `baikai-trace-otel`: the `baikai.evidence.strength` span attribute is rendered+  by `Baikai.Evidence.renderEvidenceStrength`, the function the JSON encoding+  uses, instead of a second spelling local to the sink that could drift from it.++- `baikai-trace-otel`: `gen_ai.response.model` is set only by the evidence+  branch, from the model the provider reported. The terminal branch set it from+  the *requested* id, and since evidence is pushed before the terminal and+  `addAttributes` replaces a key, that both labelled a request as an observation+  on every call without evidence and overwrote the genuinely observed value on+  every call with one. (REV-2 D.1.)++## [baikai-effectful 0.4.0.0] - 2026-08-28++### Changed++- `baikai-effectful` (breaking): the version is a **major** bump although this+  package's own exports are unchanged. Its `baikai` bound moves to `^>=0.6.0`,+  and the `Baikai` effect's three operations are typed in `Model`, `Context`,+  `Options` and `Response` — every one of which baikai 0.6.0.0 changes+  breakingly. A consumer therefore meets a break through this package even+  though nothing in it was renamed, so the number says so rather than making+  `0.3.0.4` look like a safe upgrade.++- `baikai-effectful`: no longer depends on `streamly`. Both stanzas listed it+  while every module imports only `Streamly.Data.Fold` and+  `Streamly.Data.Stream`, which are `streamly-core`. (REV-2 minor.)++## [baikai-kit 0.2.0.0] - 2026-08-28++### Added++- `baikai-kit`: `Baikai.Kit.Error` with the closed `KitError` sum, its+  `Exception` instance and `renderKitError`; `Baikai.Kit.Path.safeSourcePath`,+  which resolves an untrusted relative source below the kit checkout and refuses+  a symbolic link in any component or a canonical path outside the checkout;+  `Baikai.Kit.Manifest.itemSources`/`ItemSources`, the one pure derivation of an+  item's source list, and `supportedManifestVersions`;+  `Baikai.Kit.Sidecar.hashEntries`; `Baikai.Kit.Repo.KitRepo`/`RepoRefresh`;+  `Baikai.Kit.Install.installFrom`, `renderAvailable` and `UpdateReport`;+  `Baikai.Kit.Status.StatusReport`, `UpstreamAvailability` and the now-pure+  `renderStatusTable`; `Baikai.Kit.Command.runKitCommand`. `KitState` gains+  `KitUpstreamRefused`, rendered `refused`. (REV-2 E.5, F.10, F.11.)++- `baikai-kit`: `Baikai.Kit.Install.OverwritePolicy` (`KeepLocalEdits`,+  `OverwriteLocalEdits`), `reinstallPresent` (the network-free half of+  `updateKit`), and `PlannedWrite`/`WriteContent`/`executePlan`/`executePlanWith`+  as a test seam. `SidecarMeta` gains `installedFiles` and `installedHash`,+  which record what this tool wrote for one provider and the hash of exactly+  those bytes; `newSidecarMeta` takes both. `kit update` gains `--force`.+  (REV-2 F.12, Theme 8.2.)++### Changed++- **Breaking.** `baikai-kit`: every library function returns+  `Either KitError a` and prints nothing; only+  `Baikai.Kit.Command.runKit` prints `Error: …` and exits 1. `loadManifest`,+  `loadManifestMaybe`, `installItem`, `listAvailable`, `uninstallItem`,+  `updateKit` and `ensureKitRepo` change shape accordingly, `computeKitHash`+  takes the kit root, a base and relative file names, `kitStatus` returns a+  `StatusReport` instead of printing, and `KitUpdate`'s report is rendered by+  the caller. See `docs/adr/0013-library-code-never-calls-exitfailure.md`. A+  consumer that only calls `runKit` and `kitCommandParser` needs no change; one+  that calls the library directly binds `Right`. (REV-2 F.11.)++- `baikai-kit`: a kit is plain files. Install, the content hash and `kit status`+  resolve every listed source through `safeSourcePath`, so a kit repository that+  commits a symbolic link can no longer have a file read through it and copied+  into a provider directory. `kit status` shows such an item as `refused`.+  (REV-2 E.5 = F.10.)++- `baikai-kit`: a manifest whose `version` is not 1 or 2 is refused with+  `KitManifestVersionUnsupported` instead of being decoded and installed.+  (REV-2 F.12.)++- `baikai-kit`: an agent that lists several `files` installs all of them. The+  first becomes the provider's agent file as before, and each remaining file+  goes into a resource directory named after the agent beside it+  (`<agents dir>/<name>/<file>`), which uninstall removes with the agent. Only+  the first file used to be installed. (REV-2 F.12.)++- `baikai-kit`: `kit update` skips an item whose installed files no longer hash+  to what its sidecar recorded, printing the `--force` invocation that would+  overwrite them; `kit update --force` reinstalls anyway. Sidecars written+  before this release carry no such hash and are updated without the check.+  (REV-2 Theme 8.2.)++### Removed++- **Breaking.** `baikai-kit`: `Baikai.Kit.Path.safeUnder` (exported and unused),+  `Baikai.Kit.Manifest.agentSources` (replaced by `itemSources`) and+  `Baikai.Kit.Install.uninstallOutcomes` (absorbed by `uninstallItem`, which now+  returns the outcomes for the caller to render). The internal `requireSafe` and+  `Baikai.Kit.Status.resolveCacheOrEmpty` are gone with the exits they wrapped.++### Fixed++- `baikai-kit`: `kit status` with no cache and no network prints+  `No kit items installed.` and exits 0. It used to exit 1: the guard around+  `ensureKitRepo` caught `IOException`, which is not what `exitFailure` throws.+  (REV-2 F.11.)++- `baikai-kit`: `Baikai.Kit.Status.upstreamHash` joined the manifest `path`+  without validating it, a second unsanitised join that grew after the July+  hardening pass validated the first. Both now go through `itemSources` and+  `safeSourcePath`. (REV-2 Theme 8.1.)++- `baikai-kit`: an install that fails while renaming files into place now+  restores what was there before, or names the paths it could not restore.+  Phase two was a bare loop of renames, so a failure part-way left earlier+  renames in place while the message said "no changes were made". Temporary+  files are also created with `openTempFile`, so two concurrent installs of one+  item no longer clobber each other's staging file, and a destination that is a+  directory is refused before anything is written. (REV-2 F.12.)++- `baikai-kit`: `Baikai.Kit.Install.stripYamlFrontmatter` normalises line+  endings to LF on every branch. Input without frontmatter, and input whose+  frontmatter is never closed, used to keep their `\r` characters and leak them+  into the Codex agent TOML. (REV-2 Theme 8.7.)++- `baikai-kit`: an `IOException` raised while reinstalling during `kit update`+  is returned as `KitWriteFailed` instead of escaping as an uncaught exception.+  (REV-2 Theme 8.4.)++## [baikai-agent 0.2.0.0] - 2026-08-28++### Added++- `baikai-agent`: three operator-only `policy` keys — `policy.allowed-tools`,+  `policy.max-timeout` (a duration or `"unlimited"`) and+  `policy.max-output-limit` (a byte count or `"unlimited"`) — each defaulting+  from `defaultAgentCeiling`, and all six ceiling fields now printed by+  `agent show` and carried in its `--json` object.++- `baikai-agent`: `Baikai.Agent.Config.repositoryScopeViolations`, which reads+  the resolution report to say which values the untrusted repository file was+  not allowed to supply at all. `Baikai.Agent.Cli` concatenates its answer with+  the pure ceiling's, so an operator sees one refusal naming every problem.++### Changed++- `baikai-agent` (breaking): `AgentConfigScope`'s constructors are+  `AgentUserScope` and `AgentRepositoryScope`. `UserScope` collided with+  `baikai-kit`'s `KitScope` constructor of the same name, the one clash between+  two baikai-family packages. (REV-2 G.5.)++- `baikai-agent` (breaking): a relative `working-dir` resolves against the+  repository root rather than the process's own directory, so `working-dir "."`+  means the checkout whichever file declared it. Resolving against the process+  directory made `"."` mean two places when two documents defined one job, since+  which one it was depended on which layer won. An absolute path is unchanged.+  (REV-2 F.14.)++- `baikai-agent` (breaking): every `--json` output is now built with `aeson`+  rather than a hand-rolled writer, and `agent show --json` always emits one+  object with the same seven keys — `job`, `outcome` (`shown`, `refused` or+  `failed`), `exitCode`, `message`, `configuration`, `ceiling`, `command` —+  with `null` for the parts that do not apply. Previously a refusal emitted a+  different shape from a success and a document that would not parse emitted a+  bare resolution report or nothing at all, so a reader had to know which+  failure mode it was looking at before it could find the exit code. `run --json`+  keeps its `outcome` values and `list --json` is unchanged. (REV-2 F.14.)++- `baikai-agent` (breaking): `--run-id` or `--require-evidence` without either+  `--evidence-file` or `--json` is now a usage error (64) naming both fixes.+  Before, the record was built — a `--version` probe of the tool and two digests+  — and then dropped. Under `--json` the record now travels in the envelope as+  `evidence`, encoded by the same `ToJSON` `--evidence-file` writes.++- `baikai-agent`: `agent show` and `agent run` no longer print another job's+  unknown-key warnings, or the operator file's `policy` keys. The declaration+  describes one job and the ceiling is a separate declaration, so `settei` warns+  about both; neither is a mistake and a document with four jobs printed three+  jobs' worth of noise on every run. A misspelled key inside the selected job+  still warns, and a `policy` node in the *repository* document earns exactly one+  notice saying it has no effect. `Baikai.Agent.Config` exports the two filters,+  `relevantWarnings` and `repositoryPolicyNotice`. (REV-2 F.13.)++- `baikai-agent`: an evidence record's `endpoint` resolves a relative executable+  against the job's working directory before probing it, because that is what+  the child execs. A job whose `executable` is `./bin/agent` previously reported+  a path resolved against the parent's own directory, which does not exist.+  `Baikai.Agent.Run` exports `executableForEvidence`. (REV-2 F.13.)++- `baikai-agent`: a failed run's `error_info.message` keeps the last+  `errorInfoStderrTailBytes` (4096) bytes of standard error, prefixed with how+  many earlier bytes were dropped, instead of the whole captured stream — which+  the output limit allows to reach four mebibytes by default. `Baikai.Agent.Run`+  exports the constant. (REV-2 F.13.)++- `baikai-agent`: `--evidence-file` stages through a uniquely named temporary+  file created with `O_EXCL` beside the destination, instead of the destination+  plus `.partial`. A symbolic link planted at the old, guessable name was+  followed, which let an unattended run overwrite a file of the planter's+  choosing. (REV-2 F.13.)++- `baikai-agent` (breaking): an operator configuration file that lies inside the+  repository root is refused with exit 78, naming the file and the root, and no+  ceiling is established. The source list already refused the repository+  *document*; this closes the shape where the repository supplies the *operator*+  document, which both `--user-config .baikai/policy.kdl` and+  `XDG_CONFIG_HOME=$PWD/.baikai` produce. `--user-config`, `XDG_CONFIG_HOME` and+  `HOME` remain the operator's own inputs: the ceiling is exactly as trustworthy+  as the process environment that selects it, and the guide now says so.+  (REV-2 F.4.)++- `baikai-agent` (breaking): an unrecognised key under the operator file's+  `policy` node is an error rather than a warning, naming the file and every+  such key. Everywhere else a forward-compatible file should not stop an older+  binary; under `policy` a misspelling would silently leave the default ceiling+  in force, which for the one node whose purpose is limiting authority is+  indefensible. Two `AgentConfigError` constructors are added,+  `CeilingFileInsideRepository` and `UnknownPolicySetting`.++- `baikai-agent` (breaking): `AgentConfigPaths` gains `repositoryRoot`, the+  directory the process runs in. `--config PATH` chooses which file supplies+  repository-scope settings and does not move the root, because the root is what+  confines a repository-supplied `working-dir`.++- `baikai-agent` (breaking): a repository configuration file may no longer set+  `executable` or a non-empty `extra-dirs`, and its `working-dir` must resolve —+  after following symbolic links — inside the repository root. Each is refused+  with exit 77 naming the setting, or naming both directories. The operator's+  own file and `--set` may still set all three. `executable` turns configuration+  into code execution with the operator's environment and the prompt on standard+  input; `extra-dirs` inside the root adds nothing the working directory does not+  already give, so the only ones a checkout would ask for are outside it.+  (REV-2 F.3.)++### Removed++- `baikai-agent` (breaking): the `BAIKAI_AGENT_EXECUTABLE` environment binding.+  An environment variable is inherited by every child process and is easy to set+  by accident, and naming the program to run is the widest widening there is.+  An operator whose installation is not on `PATH` writes `executable` in their+  own configuration file or passes `--set`.++### Fixed++- `baikai-agent`: a timed-out run now **escalates to `SIGKILL`**. The runner+  interrupts the child's whole process group, then terminates it, then kills it,+  each of the first two stages bounded by the grace period and ended early once+  the leader has been reaped and no member of the group is left. Previously the+  last resort was `terminateProcess` followed by an *unbounded* wait, so a+  coding agent that ignored `SIGTERM` — or a grandchild holding the output pipe+  — hung the run for as long as it chose to live, with the deadline already+  past. Polling the group rather than waiting on the leader alone is also what+  gives a grandchild the same grace the agent gets.++- `baikai-agent`: a timed-out run **reports the output it drained**. `baikai+  agent run` prints it under the same stream discipline a finished run gets, so+  `response=$(baikai agent run job)` under `capture` receives the partial answer+  with `$?` set to 75, and `--json`'s failure envelope carries the same+  `stdout`, `stdoutTruncated`, `stderr` and `stderrTruncated` fields. A drain+  interrupted because something outside the process group still held the pipe+  open keeps its bytes too, reported as truncated.++- `baikai-agent`: the `baikai` command writes its output as **UTF-8 bytes**+  rather than through the locale encoding. Where an unattended run actually+  happens — cron, a systemd unit, a container — the environment says `LANG=C`,+  and on a platform whose locale encoding follows it a single accented character+  in the agent's answer made the write throw after the run had already finished:+  exit 1, answer lost. This mirrors what the prompt read and the prompt write+  have always done.++- `baikai-agent`: the `baikai` executable now links the **threaded runtime**+  (`ghc-options: -threaded` on the `executable baikai` stanza). Without it a+  blocking operating-system call — the `waitpid` inside+  `System.Process.waitForProcess` — stopped every Haskell thread in the+  installed binary, so a job's configured `timeout` could never fire and a+  coding agent that wrote more than one pipe buffer deadlocked against the+  runner's drain threads. Both defects existed only in the shipped executable:+  the test suite was already compiled `-threaded`, so every runner test passed+  under a runtime the binary did not have.++  The suite now proves the runtime the binary ships with rather than its own.+  `baikai-agent/test/BinaryTests.hs` spawns the built executable — cabal builds+  it first and puts it on the suite's `PATH` through+  `build-tool-depends: baikai-agent:baikai` — asserts that `baikai +RTS --info`+  reports `rts_thr`, and runs `baikai agent run` against a stub agent that+  outlives its deadline, requiring exit 75 within seconds and the whole process+  group gone. See+  [docs/adr/0006](docs/adr/0006-a-process-spawning-executable-ships-on-the-threaded-runtime.md).++## [baikai 0.5.0.0] - 2026-08-05++### Added++- `baikai`: new exposed module `Baikai.Agent`, the provider-neutral vocabulary+  for an **unattended coding-agent run** — a run with no terminal and no human,+  which owns its own tool loop, may change files inside directories the caller+  authorized, and returns a process result rather than a `Response`. It defines+  `AgentRunRequest` (with a required `workingDir`), `AgentRunResult`, the+  `AgentCapability` profile (`read-only`, `edit-workspace`, `full-access`),+  `AgentSafety`, the `AgentOutputMode` and `AgentCapturedOutput` output+  discipline, the `AgentCommand` renderer/runner boundary with an explicit+  prompt transport, and the `AgentRenderError` / `AgentRunFailure` taxonomies.++- `baikai`: the operator policy ceiling — `AgentCeiling`,+  `defaultAgentCeiling`, `CeilingViolation`, and the pure `applyAgentCeiling`.+  It returns a request unchanged when it is within the ceiling and reports+  every violation when it is not; it never clamps an over-broad request to the+  permitted value. The default ceiling permits read-only and edit-workspace+  authority and refuses full access and raw provider arguments.++  `Baikai.Agent` itself is vocabulary and pure policy algebra only: it spawns no+  process and renders no command-line flags. Those live in the vendor packages+  and in `baikai-agent`, below. The module is deliberately not re-exported from+  the umbrella `Baikai` module, because its field accessors share names with+  `Baikai.Interactive`, so `import Baikai` continues to compile unchanged.++- `baikai`: new exposed module `Baikai.Evidence`, the vocabulary for+  **verifiable model-call evidence** — a record of what actually crossed the+  boundary to a provider, as opposed to what the process was configured to ask+  for. It defines `ModelCallEvidence` and the `evidenceSchemaVersion` string+  consumers pin against, `Observed` (a deliberate non-`Maybe` for a value the+  provider either did or did not report, with no function that supplies a+  default), `ThinkingTranslation` with its `ThinkingMode` and+  `ThinkingAdjustment` enumerations describing what a requested+  reasoning-effort level actually became on the wire and every clamp, collapse,+  or drop applied on the way, `EndpointIdentity` and `TransportKind`,+  `CallStatus`, and the ascending `EvidenceStrength` scale.++  It also provides the canonical hashing core: `canonicalEncode` gives a JSON+  value exactly one byte representation (object keys sorted, no insignificant+  whitespace, numbers normalised so `1`, `1.0`, `1.00`, and `1e0` all encode as+  `1`, and a hand-written string escaper so an aeson upgrade cannot silently+  invalidate a recorded digest); `commitmentDigest` hashes a full request+  envelope, and `configurationDigest` hashes an allow-list projection+  (`configurationProjection`) that keeps configuration and replaces content with+  structural summaries, so two calls that ask the same model the same way about+  different subjects agree. The two digests are separate on purpose: the first+  binds a record to a particular request, the second is safe to compare across+  runs that legitimately differ in content.++  Nothing constructs a `ModelCallEvidence` from a real call yet, and no existing+  behaviour changed. New dependencies: `cryptohash-sha256` and+  `base16-bytestring`, both single-purpose packages chosen over a full+  cryptographic framework.++- `baikai`: `Options` gains an `evidence` field carrying an optional+  `EvidenceRequest` — the caller's run identifier, retry provenance, and how+  strictly they need evidence. A call whose `evidence` is `Nothing`, which is+  every call that does not opt in, behaves exactly as it did before: no digest+  is computed and no evidence is emitted.++- (Entry added 2026-08-27; the behaviour shipped in 0.5.0.0.) `baikai`: **strict+  evidence mode**. `EvidenceStrictness` is `EvidenceBestEffort` or+  `EvidenceRequired !EvidenceStrength`, and a caller who asks for the second+  gets a call that **refuses to start** — before any request is built or any+  connection opened — when the configuration cannot reach the strength asked+  for: `Baikai.Evidence.Build.checkEvidenceRequirements` compares the+  requirement against what the provider can deliver and against the thinking+  translation, and `completeRequest` / `streamRequest` return an error-shaped+  response or a terminal `EventError` instead of dispatching. The gate is+  pre-dispatch by design; that is the only point at which refusing is still+  free.++- (Entry added 2026-08-27; the behaviour shipped in 0.5.0.0.) `baikai`:+  **sink-failure semantics under strict mode**. `Baikai.Evidence.Build`+  exports `onSinkFailure`, `sinkFailureIsFatal` and `sinkFailureError`: a trace+  sink that throws fails an `EvidenceRequired` caller's call, because a record+  the sink did not confirm written is not a record, while a best-effort caller's+  call succeeds with the failure reported on stderr.++- (Entry added 2026-08-27; the behaviour shipped in 0.5.0.0.) **Breaking.**+  `baikai`: `Baikai.Provider.Registry.ApiProvider` gained a fourth field,+  `describeThinking :: Model -> Options -> ThinkingTranslation`, which the+  pre-dispatch strictness gate calls to learn what a provider would do with the+  caller's reasoning-effort request without sending anything. Every third-party+  provider constructed with the `ApiProvider` constructor stopped compiling.+  This was not recorded at the time; it is the defect that made 0.6.0.0 hide the+  constructor behind `apiProvider` so that the next field addition is a minor+  release.++- `baikai`: model-call evidence is now **produced and emitted**. A caller who+  sets `Options.evidence` gets exactly one `call_evidence` line per call from+  their trace sink, under every way a call can end: success, provider failure, a+  consumer that abandons the stream (status `aborted`, not `failed` — an abort+  is the consumer's doing and reporting it as a provider failure would+  misattribute it), and dispatch that found no registered handler.++  New exposed module `Baikai.Evidence.Build` bridges the vocabulary to the+  `Model` and `Options` records: `minimalEvidence` and `prepareEvidence` build a+  record, `dispatchEnvelope` supplies the request envelope for the paths where+  no adapter ran, `sanitizeEndpoint` reduces a base URL to scheme/host/port/path+  with the query string and any userinfo dropped wholesale, and `onSinkFailure`+  is the hook a future release replaces to make a strict caller's call fail when+  the trace sink does.++  Every record this release produces has `strength` `requested_only` and every+  provider-observed field set to `"unobserved"`. That is not a placeholder: it+  is a truthful record for a transport that has not yet been taught to observe+  anything. Later releases teach each transport to observe more.++  (Correction added 2026-08-27: the two paragraphs above describe the release+  inaccurately and are kept as shipped rather than rewritten. `onSinkFailure`+  did not await a future release — it shipped in 0.5.0.0 together with+  `sinkFailureIsFatal` and `sinkFailureError`, which already fail a strict+  caller's call when the sink throws. And not every 0.5.0.0 record has `strength`+  `requested_only`: the provider entries below describe what each transport+  reports, and the HTTP adapters reach `correlated` and `model_observed`.)++  **A caller who does not opt in pays nothing.** With `Options.evidence` absent+  no digest is computed, no call identifier is generated, no evidence event is+  emitted, and the request envelope is never even forced — the gate lives inside+  the shared builder rather than at each adapter's call site, and the envelope+  parameter is deliberately lazy. Both facts are guarded by tests.++- `baikai`: `TraceEvent` gains a `CallEvidence` constructor, encoded as+  `{"kind":"call_evidence", …}`. A consumer whose pattern match over `TraceEvent`+  is exhaustive must add a branch; one with a wildcard is unaffected. Filter for+  it with `jq 'select(.kind == "call_evidence") | .evidence'`. Note that a trace+  line carries its fields alongside the `kind` discriminator rather than nested+  under a `data` key, and that the evidence record inside spells its own fields+  in snake_case — the two encodings differ deliberately, because an evidence+  record must render an absent field as explicit `null` while a trace line drops+  it to stay small.++- `baikai`: `Baikai.Provider.Cli.Internal` — the module the two subprocess+  providers share — gains the vocabulary for reading what a coding-agent CLI+  reported about its own run. `CodexRunReport` and the new+  `parseCodexJsonlStream :: Stream IO ByteString -> IO CodexRunReport` fold the+  `codex exec --json` event stream into its assistant text, its thread+  identifier, and its token counts, instead of concatenating agent-message text+  and discarding everything else. `ClaudeCliReport` and+  `decodeClaudeCliResult` do the same for `claude -p --output-format json`.+  Every field but the message text is optional, because both tools' event+  schemas have changed across versions and an absent field is a genuine absence+  rather than a parse failure. **Breaking** for anyone calling+  `parseCodexJsonlStream` directly: its result type is no longer `Text`. This is+  an internal module and is documented as outside the PVP guarantee.++- `baikai`: `Baikai.Provider.Cli.Internal` also gains `ExecutableIdentity` and+  `executableIdentity`, which resolve a configured executable name to an+  absolute path and read the tool's own `--version` line. The probe is cached+  per resolved name for the lifetime of the process, because spawning it per+  model call would roughly double the process cost of the cheapest possible+  call, and it is bounded by a five-second timeout so a tool that hangs on+  `--version` cannot wedge a model call. (Corrected 2026-08-27: the entry said+  two seconds; `versionProbeMicros` has always been five.) A probe that fails records the version+  as absent rather than failing the call. It is only ever called from inside+  the evidence branch: a caller who asked for no evidence must not pay for a+  process whose only purpose is to describe a tool they were about to run+  anyway.++- `baikai`: `subprocessStrength` and `cliResponseEnvelope`, also in+  `Baikai.Provider.Cli.Internal`. The former derives a subprocess call's+  evidence strength from what the tool reported and **nothing else** — the exit+  status is deliberately not one of its arguments. The latter spells the+  response-commitment envelope with the same three keys, in the same shapes, as+  the two API transports build by hand, so a verifier holding a response can+  recompute the digest without first knowing which transport served it.++- `baikai`: `Baikai.Agent` gains `AgentRunOutcome` and `agentRunOutcome`. It+  pairs what an unattended run did — the existing+  `Either AgentRunFailure AgentRunResult` — with the evidence the runner built+  for it. The evidence is a sibling of the outcome rather than a field on+  `AgentRunResult` because the run that most needs a record is one that did not+  produce a result: a run killed by its own timeout reports+  `Left (RunTimedOut …)`, so a record hanging off the `Right` would be+  unreachable exactly there.++### Fixed++- `baikai`: a `call_evidence` event is now emitted **before** its call's+  terminal `call_finished` or `call_failed`, rather than after. The+  OpenTelemetry sink ends and removes a call's span on the terminal, so under+  the old order its evidence-attribute branch was unreachable from any real+  call and every backend saw a span with no evidence on it — nothing failed,+  the attributes were simply never there. No consumer can have depended on the+  old order, because no consumer has ever seen a `call_evidence` line.++- `baikai`: the `ThinkingFormatOpenAI` Haddock in `Baikai.Compat` listed the+  native `reasoning_effort` vocabulary as `minimal | low | medium | high`, which+  predates `xhigh` and `max`. It now lists all six and states that this shape+  alone sends the canonical baikai level verbatim while the other six clamp+  through `compatibleEffort`. No behaviour changed: the native path's exclusion+  from that clamp is deliberate and is guarded by two named tests in+  `baikai-openai/test/ShapeSpec.hs`. A reader who consulted the comment to+  decide whether `xhigh` was safe to use against OpenAI has until now been told+  something untrue.++### Changed++- **Breaking:** `baikai`: `TerminalPayload` gains an `evidence` field and the two+  terminal smart constructors take it as their new first argument:+  `doneTerminal :: Maybe ModelCallEvidence -> Maybe Text -> StopReason -> Message -> TerminalPayload`+  and `errorTerminal` likewise. `Response` gains the same field. A custom+  provider implementation must pass `Nothing` (or a record it builds through+  `Baikai.Evidence.Build`); a custom `Response` built with the record+  constructor must add `evidence = Nothing`. Code that only pattern-matches on+  these types is unaffected.++- **Breaking:** `baikai`: `CallFinished` gains `cachedInputTokens`,+  `cacheWriteTokens`, `reasoningTokens`, and `totalTokens`. The trace path used+  to drop counts that `Baikai.Cost.Log.CallLogEntry` kept from the same `Usage`+  value, which made the cost log strictly more faithful than the trace.++- **Breaking:** `baikai`: a computed cost of **zero is now reported as zero**+  rather than suppressed, in `CallFinished` and at all three `CallLogEntry`+  construction sites. Previously `usd` was omitted whenever the cost came out at+  zero, so "this call was free" and "baikai could not price this call" were+  indistinguishable — and the subscription-based CLI providers always price at+  zero, so that was the common case rather than a corner. **A cost dashboard+  that treated an absent `usd` as "unpriced" will now count those calls as+  costing zero.** That is the correct reading, but it changes what such a+  dashboard shows.++- **Breaking:** `baikai`: `FromJSON TraceEvent` is written out by hand instead of+  derived. The three pre-existing kinds decode exactly as before; a+  `call_evidence` line fails to parse with a message saying to read it as a+  plain `Data.Aeson.Value`. `ModelCallEvidence` has no `FromJSON` on purpose —+  it embeds a `Cost` whose exact `Rational` amounts encode through an+  approximating `Scientific`, so a decoder would return a different value than+  was encoded — and manufacturing that fidelity would be the precise failure+  this vocabulary exists to eliminate.++- `baikai`: `Baikai.Trace.Sink.renderHuman` renders a `CallEvidence` event as a+  single `EVIDENCE run=… call=… strength=…` line rather than the whole record. A+  human-readable sink is for watching calls go by; the full record is meant to+  be read out of `fileSink` output by a machine.++- `baikai`: call identifiers on the trace path are now globally unique.+  `Baikai.Evidence.newCallId` produces 32 lowercase hexadecimal characters+  carrying 128 bits — 48 bits of Unix time in milliseconds, 48 bits of a+  per-process random seed drawn once from `/dev/urandom`, and a 32-bit counter.+  The previous generator combined the process-start *second* with a+  process-local counter into 16 characters, so two processes started within the+  same second emitted identical identifier sequences; its own documentation+  claimed only per-process uniqueness. Identifiers still sort chronologically+  and are still not secrets.++  `Baikai.Trace.newEventId` keeps its name and signature, delegates to+  `newCallId`, and is now deprecated. Anything that pinned the 16-character+  width — a log parser, a fixture, a column type — must widen to 32.++- `baikai`: `renderCeilingViolation` no longer prints the raw provider arguments+  a `ProviderArgsForbidden` violation carries. It reports how many were+  requested and states that their values are not shown. Raw provider arguments+  are the one part of a job description that can hold a credential — the+  configuration layer classifies the setting secret for that reason — and a+  refusal message that quoted them defeated the classification. The constructor+  keeps its `[Text]` payload so a programmatic caller can still inspect it.++## [baikai-claude 0.5.0.0] - 2026-08-05++### Added++- `baikai-claude`: new exposed module `Baikai.Provider.Claude.Agent` with+  `ClaudeAgentConfig`, `defaultClaudeAgentConfig`, and `claudeAgentCommand`, a+  pure renderer from an unattended `AgentRunRequest` to the `claude` argument+  vector. It maps the capability profile onto `--permission-mode`+  (`plan` / `acceptEdits` / `bypassPermissions`), joins a tool allow-list into+  one `--allowedTools` argument, repeats `--add-dir` per extra directory, always+  emits `-p`, and emits `--no-session-persistence` unless `persistSession` is+  set. The prompt travels on standard input and appears nowhere in the argument+  vector. A request naming a different provider is refused with+  `ProviderMismatch`. Nothing is spawned.++- `baikai-claude`: the Anthropic Messages provider now fills in the evidence+  record it previously left blank. It records the model **Anthropic reported+  running** (read from the `message_start` event, which the adapter already+  decoded for the response id and then discarded), Anthropic's `request-id`+  correlation header, the response id, the token counts Anthropic actually+  reported, and a commitment digest over the assembled response. A field the+  provider did not report stays `"unobserved"` and is never backfilled from the+  request — in particular, a stream that fails before `message_start` reports no+  observed model at all. `strength` is `model_observed` when both the model and a+  correlation identifier arrived, `correlated` when only the identifier did, and+  `requested_only` otherwise; a 2xx status never raises it, because a 200 means+  the request was accepted, not that any particular model ran.+  `fully_observed` is unreachable on this transport, since Anthropic does not+  echo the thinking configuration it applied.++- `baikai-claude`: an evidence record's `thinking` field now describes what the+  caller's reasoning-effort preference actually became on the wire, including+  three downgrades that were previously invisible everywhere in baikai's output:+  asking for thinking on a model that does not advertise `reasoning`+  (`thinking_dropped_unsupported_model`); asking for a level whose token budget+  does not fit under the resolved output-token ceiling+  (`thinking_dropped_budget_exceeded`, carrying both colliding numbers), which is+  reachable by lowering `maxTokens` alone; and asking for `high` on an+  adaptive-thinking model, which sends no effort field and so is+  wire-indistinguishable from taking Anthropic's default depth+  (`effort_omitted`). `minimal` on an adaptive model reports `effort_clamped`,+  because Anthropic's adaptive vocabulary has no `minimal`.++- `baikai-claude`: new exports from `Baikai.Provider.Claude.Sse` —+  `ResponseMetadata` and `capturedHeaderNames` — and from+  `Baikai.Provider.Claude.Api` — `claudeMessagesStreamWith`, `SseDriver`, and+  `anthropicStrength`. Response-header capture is an **allow-list**+  (`request-id`, `x-request-id`, `cf-ray`, in that preference order), not a+  denylist, so a header a future gateway adds is not recorded by default.++- `baikai-claude` and `baikai-openai`: both subprocess providers now fill in the+  evidence record they previously left blank, and both export the translation+  function that describes it — `claudeCliThinking` and `codexCliThinking`. They+  record the session or thread identifier the tool reported, the token counts it+  reported, the model it named when it names one, the resolved executable path+  in place of an endpoint URL, the tool's own `--version` string as the+  implementation version (for this transport the tool *is* the implementation),+  a request commitment over the rendered argument vector, and a response+  commitment over the assembled answer.++  **A zero exit status never raises the strength.** A coding-agent CLI that+  exits zero has demonstrated that it ran and did not crash; it has not stated+  which model served the request. Subprocess calls almost always exit zero, so+  encoding that as corroboration would make the weakest evidence in the system+  look like the strongest. `strength` is `model_observed` only when the tool+  named both an identifier and a model, `correlated` when it named only an+  identifier, and `requested_only` otherwise.++  The two transports differ in how far they can get. `claude` names the model+  that consumed tokens in its result event's `modelUsage` map, complete with a+  context-window variant marker such as `[1m]`, so a Claude CLI run can reach+  `model_observed`. `codex-cli 0.146.0` names no model anywhere in its event+  stream, so **no** Codex CLI run can exceed `correlated` — backfilling the+  `--model` flag baikai passed would report the request as an observation.++- `baikai-claude`: an evidence record's `thinking` field now describes what a+  reasoning-effort request became on the `claude` command line: mode `flag`,+  wire field `--effort`, and an `effort_clamped` adjustment recording the+  `minimal` → `low` collapse, because the tool's `--effort` flag has no+  `minimal`. A caller asking for `minimal` and a caller asking for `low` produce+  byte-identical argument vectors — and therefore identical request commitment+  digests — so the translation is the only place that difference survives.++- **Breaking:** `baikai-claude` and `baikai-openai`: `claudeAgentCommand` and+  `codexAgentCommand` return `(AgentCommand, ThinkingTranslation)` rather than+  `AgentCommand`. The runner deliberately imports no vendor renderer, so it+  cannot derive the translation and has to be handed it. A caller that only+  wants the command writes `fmap fst`. Both modules also export the translation+  function alone — `claudeAgentThinking` and `codexAgentThinking` — for asking+  what a level would become without rendering anything.++### Fixed++- **Loud:** `baikai-claude` and `baikai-openai`: both subprocess providers+  hardcoded `usage = zeroUsage` on every call, so a cost dashboard saw every+  `claude -p` and `codex exec` call as consuming no tokens and costing nothing.+  Both tools report their own token counts and baikai now carries them through,+  normalized into the disjoint `Usage` convention: `claude`'s counts are+  Anthropic-shaped and already disjoint, while `codex` reports OpenAI-style+  inclusive prompt counts, so its cached tokens are subtracted out of+  `inputTokens`. `claude` additionally reports a `total_cost_usd`, which now+  populates `Usage.cost` exactly rather than being reported as zero.++  **A dashboard that read these calls as free will now see real tokens and, for+  `claude`, a real cost.** That is the correction, not a regression — but it+  changes what existing reports show, and totals over historical data will not+  match totals over new data.++- `baikai-claude`: `Response.responseId` was always `Nothing` on the `claude -p`+  transport even though `ClaudeCliResult` decoded the tool's `session_id` one+  screen earlier and then dropped it. It now carries that identifier, on both+  the successful and the failed terminal. `baikai-openai`: the same for+  `codex exec`, whose thread identifier was filtered out of the event stream+  along with everything that was not an `agent_message`. These are the handles+  each vendor's support tooling looks a run up by.++### Changed++- **Breaking:** `baikai-claude`: `Baikai.Provider.Claude.Sse`'s four streaming+  entry points — `claudeSseStream`, `claudeSseStreamValue`,+  `claudeSseStreamValueWithHeaders`, and `sseFromResponse` — take a new+  `ResponseMetadata -> IO ()` callback immediately before the existing per-event+  callback. It fires exactly once, before the first event, on both the success+  and the non-2xx path. Pass `(\_ -> pure ())` to keep the previous behaviour.+  The callback is separate rather than a widening of the per-event one because+  the per-event callback runs once per SSE frame and response-level data does not+  belong on that path.++- **Breaking:** `baikai-claude`: `Baikai.Provider.Claude.Internal.Request`'s+  `mapRequest` now returns+  `Either Text (Messages.CreateMessage, ThinkingTranslation)` and+  `computeThinking` returns `(ThinkingPlan, ThinkingTranslation)`. Take `fst` to+  keep the previous value. This module is exposed for provider tests and+  debugging and its header states it is not covered by PVP compatibility+  guarantees, but the change is recorded here because that is not a licence to+  break a consumer silently.++- **Breaking:** `baikai-claude`: `claudeInteractiveCommand` now returns+  `Either AgentRenderError (FilePath, [String])` and `launchClaudeInteractive`+  returns `IO (Either AgentRenderError InteractiveLaunchResult)`. A request+  whose `safety` is a `CodexSandbox` policy — which Claude Code cannot express+  — is refused with `SafetyNotExpressible AgentClaude`, naming the rejected+  sandbox mode and approval policy and suggesting `ClaudeAllowedTools` or+  `DefaultSafety`. Previously the policy was silently discarded and an+  **unrestricted** Claude session was started and reported as a success. A+  `Left` means no process was started; a `Right` with a non-zero exit code+  means the session ran and exited non-zero. `DefaultSafety` and an empty+  `ClaudeAllowedTools` list still render no safety flag and are never refused,+  and no previously rendered argument vector changed. Callers must handle the+  refusal branch.++## [baikai-openai 0.5.0.0] - 2026-08-05++### Added++- `baikai-openai`: new exposed module `Baikai.Provider.OpenAI.Agent` with+  `CodexAgentConfig`, `defaultCodexAgentConfig`, and `codexAgentCommand`, the+  same renderer for `codex exec`. It maps the capability profile onto+  `--sandbox` (`read-only` / `workspace-write` / `danger-full-access`), emits+  `--cd` for the working root, and defaults `--skip-git-repo-check` and+  `--ephemeral` on. A request carrying a tool allow-list is **refused** with+  `UnsupportedToolRestriction`, because `codex exec` has no such flag and running+  it with unrestricted tools would grant more authority than the caller asked+  for. Nothing is spawned.++- `baikai-openai`: an evidence record's `thinking` field now describes what the+  caller's reasoning-effort preference became on the wire for the specific host+  the call went to, across **all seven** OpenAI-compatible wire shapes. The+  OpenAI-native shape sends the canonical level verbatim and records no+  adjustment, because it expresses every level exactly. The four shapes that+  carry an effort word for a non-native host record `effort_clamped` whenever+  the word differs from the canonical name — `minimal` becomes `low`, and both+  `xhigh` and `max` become `high`. Z.ai and Qwen accept a bare+  `enable_thinking: true` with no depth, so **every** level records+  `effort_collapsed_to_toggle`: a caller asking for `max` and a caller asking+  for `low` produce byte-identical requests there, and only the evidence record+  can tell them apart. A host with no reasoning controls records+  `thinking_dropped_unsupported_host` where the option previously vanished with+  no trace. A forty-two-row table test pins the translation and the shaped+  request body for every shape at every level.++- `baikai-openai`: the Chat Completions provider now fills in the evidence record+  it previously left blank. It records the model **the host reported running**+  (read from the first streamed chunk carrying a top-level `model` field and+  never overwritten by a later one), the host's `x-request-id` correlation+  header, the response id, the token counts the host actually reported, and a+  commitment digest over the assembled response. A field the host did not report+  stays `"unobserved"` and is never backfilled from the request — in particular,+  a call that fails before any chunk arrives reports no observed model at all.+  `strength` is `model_observed` when both the model and a correlation+  identifier arrived, `correlated` when only the identifier did, and+  `requested_only` otherwise; a 2xx status never raises it, because a 200 means+  the request was accepted, not that any particular model ran.+  `fully_observed` is unreachable on this transport, since no host in this+  ecosystem echoes the reasoning configuration it applied.++- `baikai-openai`: new exports from `Baikai.Provider.OpenAI.Sse` —+  `ResponseMetadata` and `capturedHeaderNames` — and from+  `Baikai.Provider.OpenAI.Api` — `openaiChatStreamWith` and `SseDriver`.+  Response-header capture is an **allow-list** (`x-request-id`, `request-id`,+  `x-amzn-requestid`, `x-ms-request-id`, `cf-ray`, in that preference order),+  not a denylist, so a header a future gateway adds is not recorded by default.+  The list is longer than the Anthropic one because this transport speaks to an+  open-ended set of hosts and the gateways commonly in front of them.++- `baikai-openai`: the same field for `codex exec`: mode `flag`, wire field+  `model_reasoning_effort`, and **no** adjustments at any level. Codex is the+  only transport in baikai that expresses all six canonical levels exactly, and+  a test asserts each one reaches the command line verbatim.++### Fixed++- `baikai-openai`: `Response.responseId` was always `Nothing` on the Chat+  Completions transport, although every compatible host sends a top-level `id`+  on every streamed chunk. It now carries the identifier the host reported, on+  both the successful and the failed terminal.++### Changed++- **Breaking:** `baikai-openai`: `Baikai.Provider.OpenAI.Sse`'s four streaming+  entry points — `openaiSseStream`, `openaiSseStreamValue`,+  `openaiSseStreamValueWithHeaders`, and `sseFromResponse` — take a new+  `ResponseMetadata -> IO ()` callback immediately before the existing per-chunk+  callback. It fires exactly once, before the first chunk, on both the success+  and the non-2xx path — a failed call's correlation identifier is if anything+  more valuable than a successful one's. Pass `(\_ -> pure ())` to keep the+  previous behaviour. The callback is separate rather than a widening of the+  per-chunk one because that one runs once per SSE frame and response-level data+  does not belong on that path.++- **Breaking:** `baikai-openai`: `Baikai.Provider.OpenAI.Api`'s `RawChunk` gains+  `model` and `responseId` fields, both `Maybe Text`. Code that pattern-matches+  on `RawChunk` is unaffected; code that constructs one with record syntax must+  add them.++- **Breaking:** `baikai-openai`: `Baikai.Provider.OpenAI.Shape`'s+  `shapeRequestBody`, `streamRequestBody`, and `injectThinkingShape` now return+  `(Aeson.Value, ThinkingTranslation)` instead of a bare body. Take `fst` to+  keep the previous value. The description has to travel out of the shaping step+  because nothing downstream can recompute it: it depends on the host's+  `ThinkingFormat`, which only the compat lookup knows. **No request body+  changed** — every one of the seven shapes puts exactly the same bytes on the+  wire as before.++- **Breaking:** `baikai-openai`: `codexInteractiveCommand` now returns+  `Either AgentRenderError (FilePath, [String])` and `launchCodexInteractive`+  returns `IO (Either AgentRenderError InteractiveLaunchResult)`. A request+  whose `safety` is a non-empty `ClaudeAllowedTools` list — which `codex` has+  no flag for — is refused with `SafetyNotExpressible AgentCodex`, quoting the+  rejected tools and suggesting `CodexSandbox` or `DefaultSafety`. Previously+  the allow-list was silently discarded and Codex was started with its default+  sandbox. The same `Left`/`Right` reading applies, `DefaultSafety` and an+  empty allow-list are never refused, and no previously rendered argument+  vector changed. Callers must handle the refusal branch.++  Both changes make the interactive surface honor the same contract as the new+  unattended surface: a safety policy the chosen provider cannot express fails+  visibly instead of silently becoming a weaker policy. Downstream consumers+  must adapt before upgrading; the known one is `shinzui/seihou`, whose+  `Seihou.CLI.AgentLaunchExec` module builds interactive launch requests.++## [baikai-trace-otel 0.3.0.3] - 2026-08-05++### Added++- `baikai-trace-otel`: the sink attaches an evidence record's salient fields to+  the open span as flat attributes (`baikai.evidence.run_id`,+  `baikai.evidence.call_id`, `baikai.evidence.strength`, the two digests, and+  `gen_ai.response.model` only when the provider actually reported one) rather+  than serialising the record into one blob. A `CallEvidence` event neither+  opens nor closes a span.++### Changed++- `baikai-trace-otel`: widened its `baikai` bound to admit `0.5`. No API change.++## [baikai-effectful 0.3.0.3] - 2026-08-05++### Changed++- Widened its `baikai` bound to admit `0.5`. No API change; the package's+  own surface is untouched.++## [baikai-kit 0.1.0.4] - 2026-08-05++### Changed++- Widened its `baikai` bound to admit `0.5`. No API change; the package's+  own surface is untouched.++## [baikai-agent 0.1.0.0] - 2026-08-05++### Added++- `baikai-agent`: **new package** (`0.1.0.0`) holding the unattended+  coding-agent runner. `Baikai.Agent.Run.runAgentCommand` takes an+  `AgentRunRequest` and an already-rendered `AgentCommand` and spawns the tool+  with no terminal and no human present. It delivers the prompt on standard+  input and closes the handle, drains standard output and standard error+  concurrently so a chatty agent cannot deadlock on a full pipe, retains at most+  `outputLimit` bytes per stream while reading and discarding the excess, and+  honors the three output disciplines. Preconditions run before any spawn: a+  missing working directory is `WorkingDirMissing` and unset or empty declared+  variables are `MissingEnvironment`, listing all of them at once. On timeout+  the child's whole process group is interrupted, given a grace period, and then+  terminated, so the agent's own child processes go with it; the failure reports+  the configured limit. A non-zero exit code is a successful run carrying that+  code, not a failure. The runner consumes an already-rendered `AgentCommand`+  and never imports a vendor renderer, so it is exercised entirely with+  hand-written argument vectors. Its POSIX-signal escalation is conditional on a+  non-Windows build.++- `baikai-agent`: new exposed module `Baikai.Agent.Config`, the layered+  configuration layer. `resolveAgentJob` resolves one named job across five+  layers — built-in defaults, the operator file, the repository file, the+  environment, then command-line overrides, later layers winning — and returns+  the resolved `AgentJob` together with a report attributing every value to the+  file, line, and column it came from. `agentJobRequest` converts a job into an+  `AgentRunRequest`, taking the prompt at call time. `listAgentJobs` enumerates+  configured job names, sorted, each attributed to the highest-precedence scope+  defining it. `defaultAgentConfigPaths` locates+  `$XDG_CONFIG_HOME/baikai/agents.kdl` (or `$HOME/.config/baikai/agents.kdl`)+  and `./.baikai/agents.kdl`, with no upward search through parent directories.++  The **policy ceiling** is loaded by a separate function, `loadAgentCeiling`,+  against a separate source list containing the operator file and nothing else:+  no repository file, environment variable, or command-line override can raise+  it. `applyCeilingToJob` refuses an over-broad request with `CeilingRejected`+  rather than clamping it. With no operator file the ceiling is+  `defaultAgentCeiling`. `safety.provider-args` is classified secret and renders+  as `<redacted>` in any report or structured error.++  New dependencies: `settei`, `settei-env`, `settei-kdl`, and+  `settei-optparse-applicative` (all `^>=0.2`, published on Hackage at+  `0.2.0.0`), plus `containers` and `filepath`. `settei-formats` is deliberately+  excluded, because it bundles Dhall loading and repository configuration is+  untrusted input here.++- `baikai-agent`: the **`baikai` executable**, with the `agent run`,+  `agent show`, and `agent list` commands, and the `Baikai.Agent.Cli` module+  that implements them. A shell script now invokes one stable command, supplies+  a prompt on standard input, and selects Claude Code or Codex entirely through+  configuration.++  `agent run` resolves the named job, caps it against the operator ceiling,+  renders it through the vendor renderer for its provider, and spawns it. The+  agent's own exit code passes through unchanged; Baikai's own failures use 64+  and above following the `sysexits` convention — 64 for a usage error or an+  empty prompt, 69 when the executable could not be started, 70 for malformed+  output, 75 for a timeout, 77 for a policy refusal, and 78 for a configuration+  problem. The prompt comes from `--prompt-stdin`, `--prompt-file`, or+  `--prompt`, which are mutually exclusive, and is decoded as UTF-8 explicitly+  rather than through the handle's locale encoding.++  `agent show` performs the whole pipeline except spawning and prints each+  resolved value with the file, line, and column it came from, the policy+  ceiling in force and where it was read, and the exact argument vector that+  would be spawned — with `<redacted>` in place of any raw provider argument. A+  job whose policy is refused prints its configuration first and then the+  refusal. `agent list` enumerates configured jobs and the scope each came from.++  Every Baikai diagnostic goes to standard error. The agent's own output follows+  the job's output mode, so `response=$(baikai agent run job)` yields the+  agent's answer alone for a capturing job. `--set KEY=VALUE` overrides one+  setting of the selected job through `settei`'s own command-line source, so an+  override is attributed with the same fidelity as a file. `--json` emits+  exactly one JSON object per command.++  New dependencies for `baikai-agent`: `baikai-claude`, `baikai-openai`, and+  `optparse-applicative`. The provider packages are needed only so that+  `renderJobCommand`, the single provider dispatch point in the codebase, can+  reach both renderers. This is the first dependency in the workspace from+  `baikai-agent` onto the provider packages, so `baikai-agent` now publishes+  after all three of `baikai`, `baikai-claude`, and `baikai-openai`.++  The user guide `docs/user/unattended-agent-runs.md` documents the whole+  surface: the three commands with their flags, exit codes, and stream+  discipline; the KDL job format and layer precedence; the operator ceiling and+  redaction; the capability mapping tables for both tools; and a before-and-after+  migration of a script that embeds provider flags today.+  `docs/user/cli-providers.md` and `docs/user/interactive-launches.md` link to+  it, and the capability mapping tables moved there from the latter.++- `baikai-agent`: **an unattended coding-agent run now produces model-call+  evidence.** This surface previously had no observability of any kind: no trace+  sink, no `Response`, no usage, no identifiers. An operator could show that a+  process started, exited, and took some time; they could not show which model+  ran, which reasoning effort was applied, or which agent session the run+  corresponds to in the vendor's records.++  A record carries the run and call identifiers, the resolved executable and its+  own reported version, digests over the request, the requested model and what+  the reasoning-effort request became on the command line, whatever the tool+  reported about itself, the outcome, and an honest strength.++  **A zero exit status never raises the strength.** On this surface that rule+  matters more than anywhere else, because almost every unattended run exits+  zero. A coding agent that exits zero has demonstrated that it ran, not which+  model served it.++  Two things gate what a record can prove, and neither is the default. The job+  must **capture** output — under `inherit` the agent's bytes went to the+  operator's terminal and baikai never held them — and the tool must be+  configured to print a structured format, which means `--output-format json`+  for `claude` or `--json` for `codex exec` through the job's `provider-args`.+  Without both, the tool's session identifier, model, and token counts are+  genuinely unavailable and the record says `"unobserved"` rather than inferring+  anything. A timed-out run records `aborted`; a run that never started records+  nothing at all.++- **Breaking:** `baikai-agent`: `Baikai.Agent.Run.runAgentCommand` takes two new+  leading arguments and returns the new outcome type:+  `Maybe EvidenceRequest -> ThinkingTranslation -> AgentRunRequest -> AgentCommand -> IO AgentRunOutcome`.+  A caller who wants the previous behaviour passes `Nothing` and+  `Baikai.Evidence.noThinkingRequested` and reads the `outcome` field; that path+  is byte-for-byte what it was, and costs what it cost — no digest is computed,+  no call identifier is generated, and the tool is not invoked a second time to+  read its version.++- `baikai-agent`: `baikai agent run` gains `--evidence-file PATH` and+  `--run-id TEXT`. Supplying neither leaves the run on the pre-existing path at+  the pre-existing cost; supplying either turns recording on, with the job's own+  name standing in as the run identifier when only a destination is given. The+  file is written atomically — a staging file beside the destination, then a+  rename — so a reader polling the path never sees a half-written object, and it+  is never appended to. A failed write is reported on standard error and never+  changes the exit code, because the agent's own status is what a calling script+  branches on. `docs/user/unattended-agent-runs.md` documents both options and,+  more importantly, what the record does and does not prove.++- `baikai-agent`: `baikai agent run` gains `--require-evidence STRENGTH`, taking+  `requested_only`, `correlated`, `model_observed`, or `fully_observed` — the+  same words a record's `strength` field spells, so what one record showed can+  be passed back as the next run's requirement. A job whose configuration cannot+  produce evidence of at least that strength is refused before anything is+  spawned, exiting 77 — the code a ceiling violation and an inexpressible safety+  policy already use, so a script branching on 77 needs no new case.++## [baikai-claude 0.4.0.1] - 2026-07-30++### Fixed++- Widened the `crypton` bound from `^>=1.0` to `>=1.0 && <1.2` so consumers can+  build `baikai-claude` alongside packages that require `crypton` 1.1.x (for+  example `pg-migrate-1.1.0.0`), which previously had no solvable build plan.+  The only `crypton` use is `Crypto.Hash` (`Digest`, `SHA256`) in+  `Baikai.Provider.Claude.Transport`, whose API is identical across the 1.0/1.1+  boundary. No API change.++## [baikai 0.4.1.0] - 2026-07-20++### Changed++- Version bump only; no library API or code changes. Released so the umbrella+  release tag `baikai-0.4.1.0` names a fresh core version alongside the breaking+  `baikai-claude` / `baikai-openai` 0.4.0.0 releases, matching the tag+  convention downstream consumers pin against.++## [baikai-claude 0.4.0.0] - 2026-07-20++### Changed++- **Breaking:** `claudeCliCommand` now takes the `Options` record and forwards+  `Options.thinking` to batch `claude -p` as `--effort <level>` (`minimal`+  collapses to `low`, matching the interactive launcher and the claude CLI's+  lack of a `minimal` value). `thinking = Nothing` emits no effort flag, keeping+  existing argv byte-for-byte. The added parameter is a PVP-major signature+  change.++## [baikai-openai 0.4.0.0] - 2026-07-20++### Changed++- **Breaking:** `codexCliCommand` now takes the `Options` record and forwards+  `Options.thinking` to `codex exec` as `-c model_reasoning_effort=<level>` for+  all six effort levels. `thinking = Nothing` emits no override, keeping+  existing argv byte-for-byte. The added parameter is a PVP-major signature+  change.++## [baikai 0.4.0.0] - 2026-07-20++### Added++- Added `ThinkingXHigh` and `ThinkingMax` to the exported `ThinkingLevel`+  vocabulary and added a defaulted `InteractiveLaunchRequest.effort` field.+  Extending the closed sum type is a PVP-major API change for downstream+  exhaustive matches.++## [baikai-claude 0.3.0.2] - 2026-07-20++### Added++- Added `--effort` rendering to interactive Claude Code launches and preserved+  `xhigh` / `max` on native adaptive Anthropic API requests, with larger fixed+  budgets for manual-thinking models.++### Changed++- Bumped the internal `baikai` dependency bound to `^>=0.4.0` for the+  baikai 0.4.0.0 release.++## [baikai-openai 0.3.0.2] - 2026-07-20++### Added++- Added `model_reasoning_effort` overrides to interactive Codex launches and+  preserved `xhigh` / `max` in native OpenAI request JSON; non-native+  OpenAI-compatible request shapes continue to clamp them to `high`.++### Changed++- Bumped the internal `baikai` dependency bound to `^>=0.4.0` for the+  baikai 0.4.0.0 release.++## [baikai-trace-otel 0.3.0.2] - 2026-07-20++### Changed++- Bumped the internal `baikai` dependency bound to `^>=0.4.0` for the+  baikai 0.4.0.0 release. No API changes.++## [baikai-effectful 0.3.0.2] - 2026-07-20++### Changed++- Bumped the internal `baikai` dependency bound to `^>=0.4.0` for the+  baikai 0.4.0.0 release. No API changes.++## [baikai-kit 0.1.0.3] - 2026-07-20++### Changed++- Bumped the internal `baikai` dependency bound to `^>=0.4.0` for the+  baikai 0.4.0.0 release. No API changes.++## [baikai 0.3.1.0] - 2026-07-15++### Added++- Added `claude-sonnet-5` to the Anthropic model catalog (1M context window,+  128k max output, `tool_call` + reasoning).+- Added the `gpt-5.6` family — `gpt-5.6`, `gpt-5.6-luna`, `gpt-5.6-sol`, and+  `gpt-5.6-terra` — to the OpenAI model catalog (chat-completions with+  `tool_call` support).++### Changed++- Corrected `claude-sonnet-4-5` context window to 1M tokens and+  `claude-sonnet-4-6` max output to 128k tokens in the catalog.+- Added PVP-compliant upper bounds to all previously-unbounded library and+  executable dependencies.++## [baikai-claude 0.3.0.1] - 2026-07-15++### Changed++- Added PVP-compliant upper bounds to all previously-unbounded library and+  executable dependencies.++## [baikai-openai 0.3.0.1] - 2026-07-15++### Changed++- Added PVP-compliant upper bounds to all previously-unbounded library and+  executable dependencies.++## [baikai-trace-otel 0.3.0.1] - 2026-07-15++### Changed++- Added PVP-compliant upper bounds to all previously-unbounded library and+  executable dependencies.++## [baikai-effectful 0.3.0.1] - 2026-07-15++### Changed++- Added PVP-compliant upper bounds to all previously-unbounded library and+  executable dependencies.++## [baikai-kit 0.1.0.2] - 2026-07-15++### Changed++- Added PVP-compliant upper bounds to all previously-unbounded library and+  executable dependencies.++## [baikai 0.3.0.0] - 2026-07-03++### Added++- Added the documented record-update bases `emptyOptions`, `emptyContext`,+  `emptyModel`, `emptyResponse`, `emptyTool`, `emptyTextContent`,+  `emptyThinkingContent`, `emptyToolCall`, `emptyImageContent`,+  `emptyEmbeddingModel`, plus zero-valued bases `zeroUsage`, `zeroCost`,+  `zeroCostBreakdown`, and `zeroModelCost`.+- Added `firstEmbedding`, a total accessor for OpenAI-compatible embedding+  responses.+- Added `responseError`, `errorResponse`, `httpError`, and+  `parseRetryAfterSeconds` for the in-band error contract.++### Changed++- **Breaking:** Constructors for evolvable records are no longer exported:+  `Options`, `Context`, `Model`, `OpenAICompletionsCompat`,+  `AnthropicMessagesCompat`, and `InteractiveLaunchRequest` are built from+  exported base values plus record updates.+- **Breaking:** The `_X` base values are deprecated in favor of the new+  `empty*` and `zero*` names; the aliases remain for this release.+- **Breaking:** Removed `unModel`; use `mkModel` or `emptyModel` record+  updates.+- **Breaking:** Renamed `InteractiveLaunchRequest.model` to `modelId`.+- **Breaking:** `Response.latencyMs` and trace event `latencyMs` fields are+  now `Int`.+- **Breaking:** `completeRequest` / `completeRequestWith` no longer throw+  `BaikaiError` for unregistered API tags; they return an error-shaped+  `Response`.+- **Breaking:** CLI providers now report subprocess/decode/provider failures+  in-band as error-shaped `Response`s.+- **Breaking:** `errorTerminal` now requires a `BaikaiError`, enforcing+  structured error details for `EventError` construction sites.+- Documented that `Baikai.Prelude` is a convenience module outside the PVP+  stability contract and that `.Internal` modules have no compatibility+  guarantees.++### Fixed++- Empty embedding `data` arrays now produce a typed `decodeError` instead of+  crashing on an empty vector.+- The model-fetch JSON renderer now delegates string escaping to aeson.+- The model generator now fails on sanitized Haskell identifier collisions+  instead of rendering duplicate bindings.+- Live HTTP status, `Retry-After`, and network-failure classification now+  works on both API providers.+- `content_filter` / Anthropic refusals terminate as classified `EventError`+  terminals, and `liftCompleteToStream` preserves error-shaped responses.++## [baikai-claude 0.3.0.0] - 2026-07-03++### Changed++- **Breaking:** `Baikai.Provider.Claude.ErrorClass` moved to+  `Baikai.Provider.Claude.Internal.ErrorClass`.+- **Breaking:** `mapRequest` and pure request-shaping helpers moved from+  `Baikai.Provider.Claude.Api` to+  `Baikai.Provider.Claude.Internal.Request`.+- **Breaking:** `ClaudeCliConfig` and `ClaudeInteractiveConfig` constructors+  are no longer exported; start from their default config values and update+  fields.+- **Breaking:** CLI and interactive `extraArgs` fields are now `[Text]`.++## [baikai-openai 0.3.0.0] - 2026-07-03++### Changed++- **Breaking:** `Baikai.Provider.OpenAI.ErrorClass` moved to+  `Baikai.Provider.OpenAI.Internal.ErrorClass`.+- **Breaking:** `mapRequest` and pure request-shaping helpers moved from+  `Baikai.Provider.OpenAI.Api` to+  `Baikai.Provider.OpenAI.Internal.Request`.+- **Breaking:** `CodexCliConfig` and `CodexInteractiveConfig` constructors are+  no longer exported; start from their default config values and update fields.+- **Breaking:** CLI and interactive `extraArgs` fields are now `[Text]`.++## [baikai-trace-otel 0.3.0.0] - 2026-07-03++### Changed++- Updated the `baikai` dependency bound to `^>=0.3.0`.+- Adjusted to the core trace event `latencyMs :: Int` type.++## [baikai-effectful 0.3.0.0] - 2026-07-03++### Changed++- Updated the `baikai` dependency bound to `^>=0.3.0`.++## [baikai-kit 0.1.0.1] - 2026-07-03++### Changed++- Updated the `baikai` dependency bound to `^>=0.3.0`.++## [baikai 0.2.0.0] - 2026-06-21++### Added++- `Usage`, `Cost`, and `CostBreakdown` now have `Semigroup`/`Monoid`+  instances that add field-by-field, plus `sumUsage :: Foldable f => f+  Usage -> Usage`, so callers can total per-call usage and cost.+  `reasoningTokens` combines as presence-wins (`Nothing` only when both+  operands are `Nothing`).+- A categorised error model: `BaikaiError` is now a record carrying an+  `ErrorCategory` (`AuthError`, `RateLimited`, `ContextOverflow`,+  `InvalidRequest`, `TransientError`, `DecodeFailure`, `ProcessFailure`,+  `ProviderUnavailable`, `OtherError`), an optional HTTP `httpStatus`, a+  `retryAfterSeconds` hint, and a subprocess `exitCode`. New smart+  constructors (`providerError`, `invalidRequest`, `decodeError`,+  `processError`, `rateLimited`, `authError`, `providerUnavailable`),+  the `isRetryable` predicate, and the pure `classifyHttpStatus` /+  `classifyHttpStatusWithBody` helpers let callers implement retry+  policy without parsing error text. `ErrorCategory` and `BaikaiError`+  serialize to JSON.+- `Response` and the streaming `EventError`'s `TerminalPayload` now+  carry `errorInfo :: Maybe BaikaiError`, so a failed `completeRequest`+  (or a drained stream) exposes the structured category/retry hint+  in-band. `Baikai.Stream.Event` gains `doneTerminal` / `errorTerminal`+  constructors.++### Changed++- **Breaking:** `BaikaiError`'s four flat constructors+  (`ProviderError`, `RequestInvalid`, `DecodeError`, `ProcessError`)+  were replaced by the record above. Migrate by lowercasing to the+  smart constructors — `ProviderError "x"` becomes `providerError "x"`,+  `ProcessError n "x"` becomes `processError n "x"`, etc.+- **Breaking:** `Baikai.Stream.Event.TerminalPayload` and+  `Baikai.Response.Response` gained an `errorInfo` field; build+  `TerminalPayload` via `doneTerminal` / `errorTerminal`.++### Fixed++- Restored JSON decoding for `BaikaiError` values with omitted optional+  metadata fields.++## [baikai-claude 0.2.0.0] - 2026-06-21++### Added++- The Anthropic API and `claude -p` CLI providers now classify failures+  into the typed `BaikaiError` categories: HTTP errors (via the caught+  `servant-client` `ClientError`) map status/`Retry-After`/body onto+  `AuthError` / `RateLimited` / `ContextOverflow` / `InvalidRequest` /+  `TransientError`, and mid-stream Anthropic `error` events are+  classified by their error type. The result is surfaced on+  `Response.errorInfo`.++## [baikai-openai 0.2.0.0] - 2026-06-21++### Added++- The OpenAI/OpenAI-compatible API and `codex exec` CLI providers now+  classify failures into the typed `BaikaiError` categories the same way+  as `baikai-claude` (HTTP `ClientError` for status-based errors,+  streamed error text for mid-stream errors), surfaced on+  `Response.errorInfo`.++## [baikai-trace-otel 0.2.0.0] - 2026-06-21++### Changed++- Updated the `baikai` dependency bound to `^>=0.2.0` for compatibility with+  the `baikai 0.2.0.0` breaking API release.++## [baikai-effectful 0.2.0.0] - 2026-06-21++### Changed++- Updated the `baikai` dependency bound to `^>=0.2.0` for compatibility with+  the `baikai 0.2.0.0` breaking API release.++## [baikai 0.1.1.0] - 2026-06-12++### Added++- Added provider-agnostic `ResponseFormat` support on `Options`, including+  plain JSON-object mode and named JSON-schema mode.+- Added `Baikai.Embedding`, an OpenAI `/v1/embeddings` client for text+  embeddings.++## [baikai-claude 0.1.1.0] - 2026-06-12++### Added++- Mapped baikai `ResponseFormat` options onto Anthropic `output_config` for+  Claude API requests.+- Exported `mapRequest` for request-mapping tests and downstream inspection.++## [baikai-openai 0.1.1.0] - 2026-06-12++### Added++- Mapped baikai `ResponseFormat` options onto OpenAI Chat Completions+  `response_format`.+- Exported `mapRequest` for request-mapping tests and downstream inspection.++## [baikai-effectful 0.1.0.0] - 2026-06-12++### Added++- Initial release: effectful binding for baikai with the `Baikai` dynamic+  effect, `complete`, `streamCollect`, `streamEach`, and registry-backed+  interpreters.++## [baikai 0.1.0.0] - 2026-06-04++### Added++- Initial release: unified Haskell interface for working with multiple AI+  providers. Core modules including `Baikai`, `Baikai.Prelude`, `Baikai.Api`,+  `Baikai.Provider`, `Baikai.Provider.Registry`, `Baikai.Response`,+  `Baikai.Stream`, `Baikai.Tool`, `Baikai.Trace`, and the cost/usage modules.+- Depends on released `streamly` (`>=0.11 && <0.13`) and `streamly-core`+  (`>=0.3 && <0.5`) from Hackage, so all dependencies resolve from Hackage.++## [baikai-claude 0.1.0.0] - 2026-06-04++### Added++- Initial release: Anthropic Claude providers for the baikai abstraction,+  wrapping the `claude` package for both the Anthropic API and the `claude -p`+  CLI (`Baikai.Provider.Claude.Api`, `.Cli`, `.Interactive`).++## [baikai-openai 0.1.0.0] - 2026-06-04++### Added++- Initial release: OpenAI providers for the baikai abstraction, wrapping the+  `openai` package for OpenAI's Chat Completions API+  (`Baikai.Provider.OpenAI.Api`, `.Cli`, `.Interactive`).++## [baikai-trace-otel 0.1.0.0] - 2026-06-04++### Added++- Initial release: OpenTelemetry `TraceSink` adapter for baikai+  (`Baikai.Trace.Sink.OpenTelemetry`), emitting one OTel span per provider call+  with GenAI semantic-convention attributes plus baikai cost and latency.

@@ -1,20 +1,22 @@-cabal-version: 3.4-name:          baikai-trace-otel-version:       0.3.0.3-synopsis:      OpenTelemetry TraceSink for baikai.+cabal-version:   3.4+name:            baikai-trace-otel+version:         0.4.0.0+synopsis:        OpenTelemetry TraceSink for baikai. description:   Provides an opt-in OpenTelemetry adapter for the baikai 'TraceSink'   interface. Wiring 'otelSink' into 'Baikai.Trace.withTrace' produces   one OTel span per provider call, with GenAI semantic-convention   attributes plus baikai-specific cost and latency. -category:      AI, Monitoring-license:       BSD-3-Clause-license-file:  LICENSE-author:        Nadeem Bitar-maintainer:    nadeem@gmail.com-copyright:     (c) 2026 Nadeem Bitar-build-type:    Simple+category:        AI, Monitoring+license:         BSD-3-Clause+license-file:    LICENSE+author:          Nadeem Bitar+maintainer:      nadeem@gmail.com+copyright:       (c) 2026 Nadeem Bitar+build-type:      Simple+tested-with:     GHC ==9.12.4+extra-doc-files: CHANGELOG.md  common common-options   ghc-options:@@ -50,13 +52,13 @@   hs-source-dirs:  src   exposed-modules: Baikai.Trace.Sink.OpenTelemetry   build-depends:-    , baikai                                 ^>=0.5.0+    , baikai                                 ^>=0.6.0     , base                                   >=4.20   && <5     , containers                             ^>=0.7     , hs-opentelemetry-api                   >=1.0    && <1.1     , hs-opentelemetry-semantic-conventions  >=1.40   && <2     , scientific                             ^>=0.3-    , streamly-core                          ^>=0.3+    , streamly-core                          >=0.3    && <0.5     , text                                   ^>=2.1     , time                                   ^>=1.14     , unordered-containers                   ^>=0.2@@ -66,10 +68,11 @@   type:           exitcode-stdio-1.0   hs-source-dirs: test   main-is:        Main.hs+  other-modules:  PublicSurfaceSpec   ghc-options:    -threaded -with-rtsopts=-N   build-depends:     , aeson                                ^>=2.2-    , baikai                               ^>=0.5.0+    , baikai                               ^>=0.6.0     , baikai-trace-otel     , base     , generic-lens@@ -77,7 +80,7 @@     , hs-opentelemetry-exporter-in-memory  >=1.0    && <1.1     , hs-opentelemetry-sdk                 >=1.0    && <1.1     , lens                                 ^>=5.3-    , streamly-core                        ^>=0.3+    , streamly-core                        >=0.3    && <0.5     , tasty     , tasty-hunit     , text

@@ -1,5 +1,6 @@ {-# LANGUAGE LambdaCase #-} {-# LANGUAGE NamedFieldPuns #-}+{-# LANGUAGE OverloadedRecordDot #-}  -- | OpenTelemetry adapter for the baikai 'TraceSink' interface. --@@ -16,10 +17,14 @@ -- matching 'CallFinished' or 'CallFailed' closes the span and removes the -- entry. The fold's finalizer closes any spans still in flight at -- end-of-stream so no span ever leaks.+--+-- Every span is a root unless 'OtelSinkOptions.parentContext' supplies+-- one; see that field for why the parent is fixed per sink rather than+-- read from the ambient context. module Baikai.Trace.Sink.OpenTelemetry   ( otelSink,     otelSinkWith,-    OtelSinkOptions (..),+    OtelSinkOptions (spanName, includePromptSummary, parentContext),     defaultOtelSinkOptions,   ) where@@ -31,11 +36,13 @@ import Data.HashMap.Strict qualified as HashMap import Data.Int (Int64) import Data.Map.Strict qualified as Map+import Data.Maybe (fromMaybe) import Data.Scientific qualified as Scientific import Data.Text (Text) import Data.Time (UTCTime) import Data.Time.Clock.POSIX (utcTimeToPOSIXSeconds) import Data.Word (Word64)+import GHC.Generics (Generic) import OpenTelemetry.Attributes qualified as Attr import OpenTelemetry.Attributes.Map qualified as AttrMap import OpenTelemetry.Common (Timestamp, mkTimestamp)@@ -45,21 +52,43 @@ import Streamly.Data.Fold qualified as Fold  -- | Tunable knobs for 'otelSinkWith'.+--+-- Construction: the constructor is deliberately not exported. Start+-- from 'defaultOtelSinkOptions' and override fields by record update,+-- so that a field added in a later release cannot break a call site. data OtelSinkOptions = OtelSinkOptions   { -- | Name to give each emitted span. Default: @"baikai.call"@.     spanName :: !Text,     -- | If 'True', attach the redacted prompt summary as     -- @gen_ai.prompt_summary@. 'False' by default to avoid logging user     -- content into observability backends.-    includePromptSummary :: !Bool+    includePromptSummary :: !Bool,+    -- | The context whose span becomes the parent of every span this+    -- sink opens. 'Nothing', the default, makes each call span a root,+    -- as it always was.+    --+    -- A value fixed when the sink is built, not an action run per call:+    -- the fold runs on baikai's trace worker thread, where the caller's+    -- thread-local context is invisible, so reading the ambient context+    -- at span-creation time would read the worker's, which is empty. To+    -- nest a call under your own span, capture the context on your own+    -- thread — @ctx <- getContext@, or+    -- @Context.insertSpan mySpan Context.empty@ — and build the sink for+    -- that request.+    parentContext :: !(Maybe Context.Context)   }+  -- No 'Eq' or 'Show': 'OpenTelemetry.Context.Context' has neither, and+  -- a hand-written instance ignoring the field would be a lie. 'Generic'+  -- is here so @#spanName@ resolves without the constructor.+  deriving stock (Generic)  -- | Defaults: span name @baikai.call@, prompt summary off. defaultOtelSinkOptions :: OtelSinkOptions defaultOtelSinkOptions =   OtelSinkOptions     { spanName = "baikai.call",-      includePromptSummary = False+      includePromptSummary = False,+      parentContext = Nothing     }  -- | Adapt a 'Otel.Tracer' to a baikai 'TraceSink' with the default options.@@ -84,7 +113,7 @@   Map.Map Text Otel.Span ->   TraceEvent ->   IO (Map.Map Text Otel.Span)-stepEvent tracer OtelSinkOptions {spanName, includePromptSummary} m ev = case ev of+stepEvent tracer OtelSinkOptions {spanName, includePromptSummary, parentContext} m ev = case ev of   CallStarted {eventId, timestamp, provider, model, maxTokens, promptSummary} -> do     let baseAttrs :: HashMap.HashMap Text Attr.Attribute         baseAttrs =@@ -105,9 +134,17 @@               Otel.attributes = attrs,               Otel.startTime = Just (utcToTimestamp timestamp)             }-    sp <- Otel.createSpan tracer Context.empty spanName sargs+    sp <- Otel.createSpan tracer (fromMaybe Context.empty parentContext) spanName sargs     pure (Map.insert eventId sp m)-  CallFinished {eventId, timestamp, model, latencyMs, inputTokens, outputTokens, usd} ->+  -- 'model' is deliberately not bound here. It is the /requested/ model+  -- id on every 'TraceEvent' constructor, and 'gen_ai.response.model'+  -- names what the provider served — an observation, which arrives on+  -- 'CallEvidence' as 'observedModel'. Setting it here labelled the+  -- requested id as the response model on every call that had no+  -- evidence, and, because 'Otel.addAttributes' replaces an existing key+  -- and evidence is pushed before the terminal, overwrote the genuinely+  -- observed value on every call that did.+  CallFinished {eventId, timestamp, latencyMs, inputTokens, outputTokens, usd} ->     case Map.lookup eventId m of       -- A terminal without a live span is unreachable for normal withTraceStream       -- usage because each traced call drives a fresh fold. Keep the silent drop so@@ -119,10 +156,9 @@               maybe id (\n -> AttrMap.insertByKey SC.genAi_usage_inputTokens (fromIntegral n :: Int64)) inputTokens $                 maybe id (\n -> AttrMap.insertByKey SC.genAi_usage_outputTokens (fromIntegral n :: Int64)) outputTokens $                   maybe id (\s -> HashMap.insert "baikai.cost.usd" (Attr.toAttribute (Scientific.toRealFloat s :: Double))) usd $-                    AttrMap.insertByKey SC.genAi_response_model model $-                      HashMap.fromList-                        [ ("baikai.latency_ms", Attr.toAttribute latencyMs)-                        ]+                    HashMap.fromList+                      [ ("baikai.latency_ms", Attr.toAttribute latencyMs)+                      ]         Otel.addAttributes sp attrs         Otel.setStatus sp Otel.Ok         Otel.endSpan sp (Just (utcToTimestamp timestamp))@@ -178,44 +214,25 @@ -- 'Ev.Observed' type exists to prevent, and an observability backend -- gives no way to tell the two apart after the fact. ----- Read through a record pattern rather than bare selectors:+-- Read through 'OverloadedRecordDot' rather than bare selectors: -- 'Ev.ModelCallEvidence' and 'Ev.EvidenceRequest' both carry @runId@, -- so under @DuplicateRecordFields@ a bare @Ev.runId ev@ is an ambiguous--- occurrence. Matching on the constructor resolves every field at once--- and costs this package no new dependency.+-- occurrence. A record pattern would also resolve every field at once,+-- but the constructor is no longer exported. evidenceAttributes :: Ev.ModelCallEvidence -> HashMap.HashMap Text Attr.Attribute-evidenceAttributes-  Ev.ModelCallEvidence-    { Ev.schemaVersion,-      Ev.runId,-      Ev.callId,-      Ev.requestedModel,-      Ev.observedModel,-      Ev.strength,-      Ev.requestCommitment,-      Ev.requestConfiguration-    } =-    maybe id (HashMap.insert "gen_ai.response.model" . Attr.toAttribute) observed $-      HashMap.fromList-        [ ("baikai.evidence.schema_version", Attr.toAttribute schemaVersion),-          ("baikai.evidence.run_id", Attr.toAttribute runId),-          ("baikai.evidence.call_id", Attr.toAttribute callId),-          ("baikai.evidence.strength", Attr.toAttribute (strengthText strength)),-          ("gen_ai.request.model", Attr.toAttribute requestedModel),-          ("baikai.evidence.request_commitment", Attr.toAttribute requestCommitment),-          ("baikai.evidence.request_configuration", Attr.toAttribute requestConfiguration)-        ]-    where-      observed = Ev.observedValue observedModel---- | Render an 'Ev.EvidenceStrength' with the same spelling the JSON--- encoding uses, so a span attribute and a trace line agree.-strengthText :: Ev.EvidenceStrength -> Text-strengthText = \case-  Ev.EvidenceRequestedOnly -> "requested_only"-  Ev.EvidenceCorrelated -> "correlated"-  Ev.EvidenceModelObserved -> "model_observed"-  Ev.EvidenceFullyObserved -> "fully_observed"+evidenceAttributes ev =+  maybe id (HashMap.insert "gen_ai.response.model" . Attr.toAttribute) observed $+    HashMap.fromList+      [ ("baikai.evidence.schema_version", Attr.toAttribute ev.schemaVersion),+        ("baikai.evidence.run_id", Attr.toAttribute ev.runId),+        ("baikai.evidence.call_id", Attr.toAttribute ev.callId),+        ("baikai.evidence.strength", Attr.toAttribute (Ev.renderEvidenceStrength ev.strength)),+        ("gen_ai.request.model", Attr.toAttribute ev.requestedModel),+        ("baikai.evidence.request_commitment", Attr.toAttribute ev.requestCommitment),+        ("baikai.evidence.request_configuration", Attr.toAttribute ev.requestConfiguration)+      ]+  where+    observed = Ev.observedValue ev.observedModel  -- | Convert a 'UTCTime' to an OpenTelemetry 'Timestamp'. --

@@ -9,6 +9,7 @@ import Baikai.Evidence   ( CallStatus (..),     EvidenceRequest,+    Observed (..),     TransportKind (..),     evidenceRequest,     noThinkingRequested,@@ -17,14 +18,19 @@ import Baikai.Message (AssistantPayload (..), user) import Baikai.Model (Model (..), emptyModel) import Baikai.Options (Options, emptyOptions)-import Baikai.Provider (ApiProvider (..), registerApiProvider)+import Baikai.Provider (apiProviderWith, registerApiProvider) import Baikai.Response (Response (..)) import Baikai.StopReason (StopReason (..)) import Baikai.Stream (liftCompleteToStream) import Baikai.Trace (withTrace, withTraceStream) import Baikai.Trace.Event (TraceEvent (..))-import Baikai.Trace.Sink (TraceSink (..))-import Baikai.Trace.Sink.OpenTelemetry (otelSink)+import Baikai.Trace.Sink (TraceSink (..), multiSink)+import Baikai.Trace.Sink.OpenTelemetry+  ( OtelSinkOptions (..),+    defaultOtelSinkOptions,+    otelSink,+    otelSinkWith,+  ) import Baikai.Usage (Usage, zeroUsage) import Control.Concurrent (threadDelay) import Control.Exception (throwIO)@@ -38,8 +44,11 @@ import Data.Time (getCurrentTime) import Data.Vector qualified as V import OpenTelemetry.Attributes qualified as Attr+import OpenTelemetry.Context qualified as Context import OpenTelemetry.Exporter.InMemory.Span (inMemoryListExporter) import OpenTelemetry.Trace.Core qualified as Otel+import PublicSurfaceSpec qualified+import Streamly.Data.Fold qualified as Fold import Streamly.Data.Stream qualified as Stream import System.Mem (performMajorGC) import Test.Tasty (TestTree, defaultMain, testGroup)@@ -51,10 +60,14 @@     testGroup       "baikai-trace-otel"       [ successSpanTest,+        observedModelSpanTest,         failureSpanTest,         abortSpanTest,         evidenceSpanTest,-        liveEvidenceSpanTest+        liveEvidenceSpanTest,+        multiSinkSiblingSpanTest,+        parentContextTest,+        PublicSurfaceSpec.tests       ]  -- | Build a stub 'Model' under a private 'Api' tag. Each test uses@@ -105,23 +118,21 @@ registerOk a =   let handler _m _ctx _opts = pure (stubResponse a)    in registerApiProvider-        ApiProvider-          { apiTag = a,-            stream = liftCompleteToStream handler,-            complete = handler,-            describeThinking = \_ _ -> noThinkingRequested-          }+        ( apiProviderWith+            a+            (liftCompleteToStream handler)+            (handler)+        )  registerFail :: Api -> BaikaiError -> IO () registerFail a e =   let handler _m _ctx _opts = throwIO e    in registerApiProvider-        ApiProvider-          { apiTag = a,-            stream = liftCompleteToStream handler,-            complete = handler,-            describeThinking = \_ _ -> noThinkingRequested-          }+        ( apiProviderWith+            a+            (liftCompleteToStream handler)+            (handler)+        )  newTracerWithInMemory :: IO (Otel.Tracer, IO [Otel.ImmutableSpan]) newTracerWithInMemory = do@@ -157,7 +168,14 @@         assertBool "has gen_ai.operation.name" (HashMap.member "gen_ai.operation.name" attrs)         assertBool "has gen_ai.request.model" (HashMap.member "gen_ai.request.model" attrs)         assertBool "has gen_ai.request.max_tokens" (HashMap.member "gen_ai.request.max_tokens" attrs)-        assertBool "has gen_ai.response.model" (HashMap.member "gen_ai.response.model" attrs)+        -- Absent, not present: this stub reports no model, and+        -- gen_ai.response.model names what the provider served. The+        -- terminal used to set it from the /requested/ id, which is a+        -- different fact and the one gen_ai.request.model already+        -- carries.+        assertBool+          "gen_ai.response.model must be absent when the provider reported no model"+          (not (HashMap.member "gen_ai.response.model" attrs))         assertBool "has gen_ai.usage.input_tokens" (HashMap.member "gen_ai.usage.input_tokens" attrs)         assertBool "has gen_ai.usage.output_tokens" (HashMap.member "gen_ai.usage.output_tokens" attrs)         assertBool "has baikai.event_id" (HashMap.member "baikai.event_id" attrs)@@ -171,6 +189,62 @@           other -> assertFailure ("expected Client kind, got: " <> show other)       _ -> assertFailure "expected exactly one span" +-- | A sink that throws on every event, paired with the OpenTelemetry+-- sink. Under 'Fold.tee' the throw stopped delivery to the sibling and+-- skipped its end-of-stream action, so the span was opened and never+-- ended and nothing was exported. Per-member isolation ends it.+throwingSink :: TraceSink+throwingSink =+  TraceSink (Fold.drainMapM (\_ -> throwIO (providerError "sink exploded")))++multiSinkSiblingSpanTest :: TestTree+multiSinkSiblingSpanTest =+  testCase "a throwing multiSink member still lets the OTel sibling end its span" $ do+    let a = Custom "baikai-otel-multisink-sibling"+    registerOk a+    (tracer, getSpans) <- newTracerWithInMemory+    let sink = multiSink [throwingSink, otelSink tracer]+    _ <- withTrace sink (stubModel a) stubContext stubOptions+    spans <- getSpans+    assertEqual "exactly one span recorded" 1 (length spans)+    case spans of+      [sp] -> do+        hot <- spanHotSnapshot sp+        Otel.hotName hot @?= "baikai.call"+        case Otel.hotStatus hot of+          Otel.Ok -> pure ()+          other -> assertFailure ("expected Ok status, got: " <> show other)+      _ -> assertFailure "expected exactly one span"++-- | The fold runs on baikai's trace worker thread, where the caller's+-- thread-local context is invisible, so the parent is supplied as a+-- value when the sink is built. Before 'parentContext' existed every+-- call span was a root and a caller could not nest one under its own+-- request span at all.+parentContextTest :: TestTree+parentContextTest =+  testCase "parentContext nests the call span under the caller's span" $ do+    let a = Custom "baikai-otel-parent-context"+    registerOk a+    (tracer, getSpans) <- newTracerWithInMemory+    parent <- Otel.createSpan tracer Context.empty "caller.request" Otel.defaultSpanArguments+    let sink =+          otelSinkWith+            tracer+            defaultOtelSinkOptions {parentContext = Just (Context.insertSpan parent Context.empty)}+    _ <- withTrace sink (stubModel a) stubContext stubOptions+    Otel.endSpan parent Nothing+    parentCtx <- Otel.getSpanContext parent+    spans <- getSpans+    named <- mapM (\sp -> (,) sp . Otel.hotName <$> spanHotSnapshot sp) spans+    case [sp | (sp, n) <- named, n == "baikai.call"] of+      [sp] -> do+        Otel.traceId (Otel.spanContext sp) @?= Otel.traceId parentCtx+        assertBool+          "the call span records a parent"+          (maybe False (const True) (Otel.spanParent sp))+      other -> assertFailure ("expected one baikai.call span, got " <> show (length other))+ failureSpanTest :: TestTree failureSpanTest =   testCase "failure path emits one Error span with error message" $ do@@ -242,10 +316,12 @@ -- already delimits, so it must neither open a span nor close one. -- -- The sink is fed a hand-built sequence rather than driven through--- 'withTrace', for two reasons. It isolates the claim to the sink's own--- behaviour, and it is the only way to reach the attach path at all:--- "Baikai.Trace" pushes the evidence event /after/ the terminal, by--- which point the span has been ended and removed from the map.+-- 'withTrace' so the claim is about the sink's own behaviour and+-- nothing else: this case chooses the event order, which is what lets+-- it assert that an evidence event on its own neither opens a span nor+-- ends one. The live order — evidence before the terminal — is+-- 'liveEvidenceSpanTest's subject, and 'Baikai.Trace' pins it in+-- @baikai/test/TraceSpec.hs@. -- | The evidence attributes reach a span from a __live__ call, not only -- from a hand-fed stream. --@@ -313,13 +389,68 @@             Nothing         pure (stubResponse a & #evidence .~ ev)    in registerApiProvider-        ApiProvider-          { apiTag = a,-            stream = liftCompleteToStream handler,-            complete = handler,-            describeThinking = \_ _ -> noThinkingRequested-          }+        ( apiProviderWith+            a+            (liftCompleteToStream handler)+            (handler)+        ) +-- | The observed model reaches the span, and the requested one stays+-- where it belongs.+--+-- Fails on the pre-fix code with the requested id under the response+-- key: 'Baikai.Trace' pushes 'CallEvidence' before the terminal, and+-- 'Otel.addAttributes' replaces an existing key, so the terminal's+-- attribute won.+observedModelSpanTest :: TestTree+observedModelSpanTest =+  testCase "A SERVED MODEL REACHES THE SPAN AND THE REQUESTED ONE DOES NOT OVERWRITE IT" $ do+    let a = Custom "baikai-otel-observed-model"+    registerOkObservingModel a+    (tracer, getSpans) <- newTracerWithInMemory+    _ <-+      withTrace+        (otelSink tracer)+        (stubModel a)+        stubContext+        (stubOptions & #evidence .~ Just (evidenceRequest "run-otel-observed" :: EvidenceRequest))+    spans <- getSpans+    assertEqual "exactly one span recorded" 1 (length spans)+    case spans of+      [sp] -> do+        hot <- spanHotSnapshot sp+        let attrs = Attr.getAttributeMap (Otel.hotAttributes hot)+        HashMap.lookup "gen_ai.response.model" attrs+          @?= Just (Attr.toAttribute ("stub-1-as-served" :: Text))+        HashMap.lookup "gen_ai.request.model" attrs+          @?= Just (Attr.toAttribute ("stub-1" :: Text))+      _ -> assertFailure "expected exactly one span"++-- | 'registerOkWithEvidence' whose record observes a served model.+registerOkObservingModel :: Api -> IO ()+registerOkObservingModel a =+  let handler m _ctx opts = do+        now <- getCurrentTime+        ev <-+          minimalEvidence+            m+            opts+            TransportHttpApi+            noThinkingRequested+            (Aeson.object ["model" Aeson..= (m ^. #modelId :: Text)])+            now+            now+            CallSucceeded+            Nothing+        pure (stubResponse a & #evidence .~ fmap observeServedModel ev)+      observeServedModel ev = ev & #observedModel .~ Observed "stub-1-as-served"+   in registerApiProvider+        ( apiProviderWith+            a+            (liftCompleteToStream handler)+            (handler)+        )+ evidenceSpanTest :: TestTree evidenceSpanTest =   testCase "a CallEvidence event neither opens nor closes a span" $ do@@ -380,6 +511,11 @@             "baikai.evidence.request_commitment",             "baikai.evidence.request_configuration"           ]+        -- The spelling, not merely the key: the sink used to carry its+        -- own copy of the strength names in a local 'strengthText',+        -- which could drift from the one the JSON encoding writes.+        HashMap.lookup "baikai.evidence.strength" attrs+          @?= Just (Attr.toAttribute ("requested_only" :: Text))         -- The provider reported no model, so nothing may claim it did.         assertBool           "gen_ai.response.model must be absent when observedModel is Unobserved"

@@ -0,0 +1,33 @@+{-# LANGUAGE OverloadedRecordDot #-}++-- | A downstream consumer's view of @baikai-trace-otel@, compiled.+--+-- Imports only the public module and builds 'OtelSinkOptions' the way a+-- consumer now must: from 'defaultOtelSinkOptions' by record update,+-- since the constructor is no longer exported. The compilation is the+-- test.+module PublicSurfaceSpec (tests) where++import Baikai.Trace.Sink.OpenTelemetry+  ( OtelSinkOptions (includePromptSummary, parentContext, spanName),+    defaultOtelSinkOptions,+  )+import Test.Tasty (TestTree, testGroup)+import Test.Tasty.HUnit (assertBool, testCase, (@?=))++tests :: TestTree+tests =+  testGroup+    "public surface (baikai-trace-otel)"+    [ testCase "OtelSinkOptions is built from its base by record update" $ do+        let opts = defaultOtelSinkOptions {spanName = "probe", includePromptSummary = True}+        opts.spanName @?= "probe"+        opts.includePromptSummary @?= True+        -- 'Context' has no Eq, so the field is checked for absence+        -- rather than compared.+        assertBool "the default parent context is absent" (isNothingContext opts)+    ]+  where+    isNothingContext opts = case opts.parentContext of+      Nothing -> True+      Just _ -> False