diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -4,9 +4,9 @@
 
 # Status
 
-Still in development. Lacks documentation, example code, and real error messages.
+Still in development. Its handling of the `id` keyword passes tests, but is probably incorrect.
 
-Also while the official tests pass, its handling of the `id` keyword is incomplete.
+Also lacks documentation and example code.
 
 # Install Tests
 
diff --git a/hjsonschema.cabal b/hjsonschema.cabal
--- a/hjsonschema.cabal
+++ b/hjsonschema.cabal
@@ -1,5 +1,5 @@
 name:                   hjsonschema
-version:                0.2.0.0
+version:                0.3.0.0
 synopsis:               Haskell implementation of JSON Schema v4.
 homepage:               https://github.com/seagreen/hjsonschema
 license:                MIT
@@ -42,6 +42,7 @@
   default-language:     Haskell2010
   ghc-options:          -Wall
   default-extensions:   OverloadedStrings
+  other-extensions:     TemplateHaskell
   build-depends:        aeson
                       , base
                       , bytestring
@@ -62,6 +63,7 @@
   default-language:     Haskell2010
   ghc-options:          -Wall
   default-extensions:   OverloadedStrings
+  other-extensions:     TemplateHaskell
   build-depends:        aeson
                       , base
                       , bytestring
diff --git a/src/Data/JsonSchema.hs b/src/Data/JsonSchema.hs
--- a/src/Data/JsonSchema.hs
+++ b/src/Data/JsonSchema.hs
@@ -11,6 +11,7 @@
 import           Data.JsonSchema.Utils
 import           Data.JsonSchema.Validators
 import           Data.Maybe
+import           Data.Text                     (Text)
 import qualified Data.Text                     as T
 import           Data.Vector                   (Vector)
 import qualified Data.Vector                   as V
@@ -46,30 +47,31 @@
   , ("definitions"         , (noVal               , objMembersEmbed))
   ]
 
-fetchRefs :: Spec -> RawSchema -> Graph -> IO Graph
+fetchRefs :: Spec -> RawSchema -> Graph -> IO (Either Text Graph)
 fetchRefs spec a graph =
   let startingGraph = H.insert (_rsURI a) (_rsObject a) graph
-  in foldlM fetch startingGraph (includeEmbedded a)
+  in foldlM fetch (Right startingGraph) (includeSubschemas a)
 
   where
     -- TODO: optimize
-    includeEmbedded :: RawSchema -> Vector RawSchema
-    includeEmbedded r =
+    includeSubschemas :: RawSchema -> Vector RawSchema
+    includeSubschemas r =
       let newId = updateId (_rsURI r) (_rsObject r)
           xs = H.intersectionWith (\(_,f) x -> f newId x) (_unSpec spec) (_rsObject r)
           ys = V.concat . H.elems $ xs
-      in V.cons r . V.concat . V.toList $ includeEmbedded <$> ys
+      in V.cons r . V.concat . V.toList $ includeSubschemas <$> ys
 
-    fetch :: Graph -> RawSchema -> IO Graph
-    fetch g r =
+    fetch :: Either Text Graph -> RawSchema -> IO (Either Text Graph)
+    fetch (Right g) r =
       case H.lookup "$ref" (_rsObject r) >>= toTxt >>= refAndP of
-        Nothing     -> return g
+        Nothing     -> return (Right g)
         Just (s, _) ->
           let t = (_rsURI r `combineIdAndRef` s)
           in if T.length t <= 0 || H.member t g || not ("://" `T.isInfixOf` t)
-            then return g
+            then return (Right g)
             else do
               eResp <- fetchRef t
               case eResp of
+                Left e    -> return (Left e)
                 Right obj -> fetchRefs spec (RawSchema t obj) g
-                _         -> return g
+    fetch leftGraph _ = return leftGraph
diff --git a/src/Data/JsonSchema/JsonReference.hs b/src/Data/JsonSchema/JsonReference.hs
--- a/src/Data/JsonSchema/JsonReference.hs
+++ b/src/Data/JsonSchema/JsonReference.hs
@@ -51,11 +51,13 @@
 fetchRef t = do
   eResp <- safeGet t
   case eResp of
-    Left _  -> return (Left "TODO")
-    Right b ->
-      case decode b of
-        Just (Object z) -> return (Right z)
-        _               -> return (Left "TODO")
+    Left err -> return (Left err)
+    Right b  ->
+      case eitherDecode b of
+        Right (Object z) -> return (Right z)
+        Right v          -> return . Left $
+          "fetchRef returned the following instead of an object" <> T.pack (show v)
+        Left e           -> return . Left . T.pack $ e
 
 safeGet :: Text -> IO (Either Text ByteString)
 safeGet url =
diff --git a/src/Data/JsonSchema/Validators.hs b/src/Data/JsonSchema/Validators.hs
--- a/src/Data/JsonSchema/Validators.hs
+++ b/src/Data/JsonSchema/Validators.hs
@@ -1,5 +1,3 @@
-{-# LANGUAGE OverloadedLists #-}
-
 -- | This is generally meant to be an internal module.
 -- It's only exposed in case you want to make your own
 -- 'Spec'. If you just want to use JSON Schema Draft 4
@@ -66,7 +64,7 @@
 
 -- TODO: optimize
 arrayEmbed :: Text -> Value -> Vector RawSchema
-arrayEmbed t (Array vs) = V.concat . V.toList $ (\o -> objEmbed t o) <$> vs
+arrayEmbed t (Array vs) = V.concat . V.toList $ objEmbed t <$> vs
 arrayEmbed _ _ = V.empty
 
 objOrArrayEmbed :: Text -> Value -> Vector RawSchema
@@ -75,7 +73,7 @@
 objOrArrayEmbed _ _ = V.empty
 
 objMembersEmbed :: Text -> Value -> Vector RawSchema
-objMembersEmbed t (Object o) = V.concat $ (\x -> objEmbed t x) <$> H.elems o
+objMembersEmbed t (Object o) = V.concat $ objEmbed t <$> H.elems o
 objMembersEmbed _ _ = V.empty
 
 --------------------------------------------------
@@ -190,7 +188,7 @@
   Just (\x ->
     case x of
       (Array ys) -> if not val && V.length ys > 0
-        then V.singleton "TODO"
+        then V.singleton ("Val error against additionalItems false for: " <> tshow x)
         else mempty
       _ -> mempty)
 additionalItems' spec g s (Object val) =
@@ -230,7 +228,8 @@
     case x of
       (Array ys) -> if allUnique ys
         then mempty
-        else V.singleton "TODO"
+        else V.singleton
+          ("Val error against uniqueItems " <> tshow val <> " for: " <> tshow x)
       _ -> mempty)
 uniqueItems _ _ _ _ = Nothing
 
@@ -374,9 +373,9 @@
 additionalProperties' _ _ _ (Bool val) =
   Just (\x ->
     case x of
-      (Object y) -> if val || H.size y == 0
-        then mempty
-        else V.singleton "TODO"
+      (Object y) -> if not val && H.size y > 0
+        then V.singleton ("Val error against additionalProperties false for: " <> tshow x)
+        else mempty
       _ -> mempty)
 additionalProperties' spec g s (Object val) =
   let sub = compile spec g (RawSchema (_rsURI s) val)
@@ -444,7 +443,9 @@
         Nothing -> mempty
         Just _  ->
           case traverse ($ d) (H.lookup <$> ts) of
-            Nothing -> V.singleton "TODO at least one failed"
+            Nothing -> V.singleton
+              ("Val error against property dependency with the key "
+               <> t <> " and the value " <> tshow ts <> " for: " <> tshow d)
             Just _  -> mempty
 
 dependencies _ _ _ _ = Nothing
@@ -484,7 +485,7 @@
   Just (\x ->
     if V.elem V.empty (validate <$> ss <*> pure x)
       then mempty
-      else V.singleton "TODO")
+      else V.singleton ("Val error against anyOf " <> tshow vs <> " for: " <> tshow x))
 anyOf _ _ _ _ = Nothing
 
 oneOf :: ValidatorGen
@@ -494,7 +495,7 @@
   Just (\x ->
     if count V.empty (validate <$> ss <*> pure x) == 1
       then mempty
-      else V.singleton "TODO")
+      else V.singleton ("Val error against oneOf " <> tshow vs <> " for: " <> tshow x))
 oneOf _ _ _ _ = Nothing
 
 notValidator :: ValidatorGen
@@ -502,7 +503,7 @@
   let sub = compile spec g (RawSchema (_rsURI s) val)
   Just (\x ->
     if V.null $ validate sub x
-      then V.singleton "TODO"
+      then V.singleton ("Val error against not validator " <> tshow val <> " for: " <> tshow x)
       else mempty)
 notValidator _ _ _ _ = Nothing
 
@@ -526,4 +527,4 @@
 ref _ _ _ _ = Nothing
 
 noVal :: ValidatorGen
-noVal = (\_ _ _ _ -> Just (const V.empty))
+noVal _ _ _ _ = Just (const V.empty)
diff --git a/tests/Lib.hs b/tests/Lib.hs
--- a/tests/Lib.hs
+++ b/tests/Lib.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE TemplateHaskell #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 
 module Lib where
 
@@ -82,12 +83,18 @@
 
 assertValid, assertInvalid :: RawSchema -> Value -> HU.Assertion
 assertValid r v = do
-  g <- fetchRefs draft4 r H.empty
+  g <- assertRight =<< fetchRefs draft4 r H.empty
   let es = validate (compile draft4 g r) v
   unless (V.length es == 0) $ HU.assertFailure (show es)
 assertInvalid r v = do
-  g <- fetchRefs draft4 r H.empty
+  g <- assertRight =<< fetchRefs draft4 r H.empty
   let es = validate (compile draft4 g r) v
   when (V.length es == 0) $ HU.assertFailure "expected a validation error"
+
+assertRight :: (Show a) => Either a b -> IO b
+assertRight a =
+  case a of
+    Left e  -> HU.assertFailure (show e) >> fail "assertRight failed"
+    Right b -> return b
 
 $(deriveFromJSON defaultOptions { fieldLabelModifier = map toLower . drop 3 } ''SchemaTestCase)