diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,13 @@
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 0.8.4.0 - 2024-05-19
+
+### Added
+
+- `hercules-ci-api-openapi3` package in the flake, containing the experimental OpenAPI 3 spec
+- `operationId` to the endpoints in that spec
+
 ## 0.8.3.0 - 2024-05-03
 
 ### Fixed
diff --git a/hercules-ci-api.cabal b/hercules-ci-api.cabal
--- a/hercules-ci-api.cabal
+++ b/hercules-ci-api.cabal
@@ -1,6 +1,6 @@
 cabal-version:      2.2
 name:               hercules-ci-api
-version:            0.8.3.0
+version:            0.8.4.0
 synopsis:           Hercules CI API definition with Servant
 homepage:           https://github.com/hercules-ci/hercules-ci-agent#readme
 bug-reports:        https://github.com/hercules-ci/hercules-ci-agent/issues
@@ -185,6 +185,7 @@
     , hercules-ci-api
     , http-api-data
     , http-media
+    , insert-ordered-containers
     , lens
     , memory
     , network-uri
diff --git a/hercules-gen-swagger/Main.hs b/hercules-gen-swagger/Main.hs
--- a/hercules-gen-swagger/Main.hs
+++ b/hercules-gen-swagger/Main.hs
@@ -1,11 +1,19 @@
+{-# LANGUAGE OverloadedStrings #-}
+
 module Main
   ( main,
   )
 where
 
+import Control.Lens (over, (?~))
 import Data.Aeson (encode)
 import Data.Function ((&))
+import Data.HashMap.Strict.InsOrd (InsOrdHashMap, mapWithKey)
+import Data.Maybe (fromMaybe)
+import Data.OpenApi (HasPaths (paths), OpenApi, Operation, PathItem, operationId)
+import Data.OpenApi qualified as O
 import Data.String.Conv (toS)
+import Data.Text (Text)
 import Data.Text qualified as T
 import Hercules.API (openapi3, swagger)
 import System.Environment (getArgs)
@@ -19,6 +27,7 @@
     ["--experimental-openapi3"] ->
       putStrLn $
         openapi3
+          & transferOperationIds
           & encode
           & toS
           & T.replace "Attribute_(Result_AttributeError_Derivation)" "Attribute_Result_AttributeError_Derivation"
@@ -27,3 +36,66 @@
     _ -> do
       hPutStrLn stderr "Usage: hercules-gen-swagger [--experimental-openapi3] > swagger.json"
       error $ "Unknown arguments" <> show args
+
+transferOperationIds :: OpenApi -> OpenApi
+transferOperationIds = over (paths) fPathItems
+  where
+    fPathItems :: InsOrdHashMap FilePath PathItem -> InsOrdHashMap FilePath PathItem
+    fPathItems = mapWithKey fPathItem
+
+    fPathItem :: FilePath -> PathItem -> PathItem
+    fPathItem p pit =
+      pit
+        & over (O.get . traverse) (fOperation p "get")
+          . over (O.put . traverse) (fOperation p "put")
+          . over (O.post . traverse) (fOperation p "post")
+          . over (O.delete . traverse) (fOperation p "delete")
+          . over (O.options . traverse) (fOperation p "options")
+          . over (O.head_ . traverse) (fOperation p "head")
+          . over (O.patch . traverse) (fOperation p "patch")
+          . over (O.trace . traverse) (fOperation p "trace")
+
+    fOperation :: FilePath -> Text -> Operation -> Operation
+    fOperation p method o = o & operationId ?~ makeId p method o
+
+    makeId :: FilePath -> Text -> Operation -> Text
+    makeId path method _o = pathPart <> "_" <> method
+      where
+        pathPart =
+          toS path
+            & T.stripPrefix "/api/v1/"
+            & fromMaybe (toS path)
+            -- Resources by id
+            & T.replace "accounts/{accountId}" "account_by_id"
+            & T.replace "organizations/{organizationId}" "organization_by_id"
+            & T.replace "projects/{projectId}" "project_by_id"
+            & T.replace "jobs/{jobId}" "job_by_id"
+            & T.replace "cli_tokens/{cliTokenId}" "cli_token_by_id"
+            & T.replace "forges/{forgeId}" "forge_by_id"
+            & T.replace "sites/{forgeId}" "site_forge_by_id" -- legacy
+            & T.replace "gitlab/installation/{installationId}" "gitlab_installation_by_id"
+            & T.replace "clusterJoinTokens/{clusterJoinTokenId}" "cluster_join_token_by_id"
+            & T.replace "lock-leases/{lockLeaseId}" "lock_lease_by_id"
+            & T.replace "installation/{installationId}" "installation_by_id"
+            & T.replace "auth/cli/tokens/{cliTokenId}" "auth_cli_token_by_id"
+            -- Resources by name
+            & T.replace "forge/{forgeName}" "forge_by_name"
+            & T.replace "state/{stateName}" "state_by_name"
+            & T.replace "lock/{lockName}" "lock_by_name"
+            -- Resources by multiple names
+            & T.replace "site/{site}/account/{account}/project/{project}" "project_by_names"
+            & T.replace "site/{site}/account/{account}" "account_by_names"
+            -- Resources by other key
+            & T.replace "derivations/{derivationPath}" "derivation_by_path"
+            & T.replace "authorization/request/{browserToken}" "authorization_request_by_browser_token"
+            & T.replace "auth/cli/authorization/request/status/{temporaryToken}" "auth_cli_authorization_request_status_by_temporary_token"
+            & T.replace "on-schedule/{jobName}" "on_schedule_by_job_name"
+            & T.replace "evaluation/compare/{baseJobId}" "evaluation_compare_by_base_job_id"
+            -- Composite resources
+            & T.replace "effects/{attribute}" "effect_attribute"
+            -- Syntax
+            & T.replace "/" "_"
+            & T.replace "__" "_"
+            & T.replace "__" "_"
+            & T.replace "__" "_"
+            & T.replace "__" "_"