remove extra context, fix non thinking constraining

server/routes.go

@@ -1967,12 +1967,10 @@ func (s *Server) ChatHandler(c *gin.Context) {
 		toolParser = tools.NewParser(m.Template.Template, req.Tools)
 	}
 
-	ctx, cancel := context.WithCancel(c.Request.Context())
 	structuredOutputsStarted := false
 	ch := make(chan any)
 	go func() {
 		defer close(ch)
-		defer cancel()
 
 		applyStructuredOutputs := false
 
@@ -1980,12 +1978,13 @@ func (s *Server) ChatHandler(c *gin.Context) {
 			var tb strings.Builder
 
 			currentFormat := req.Format
-			if req.Format != nil && !structuredOutputsStarted {
+			// set format to nil if a parser exists and structured outputs haven't started
+			if req.Format != nil && !structuredOutputsStarted && (thinkingState != nil || builtinParser != nil) {
 				currentFormat = nil
 			}
 
-			// sets up new context given parent context
-			requestCtx, requestCancel := context.WithCancel(ctx)
+			// sets up new context given parent context per request
+			requestCtx, requestCancel := context.WithCancel(c.Request.Context())
 			err := r.Completion(requestCtx, llm.CompletionRequest{
 				Prompt:  prompt,
 				Images:  images,
@@ -2081,7 +2080,7 @@ func (s *Server) ChatHandler(c *gin.Context) {
 				ch <- res
 			})
 			if err != nil {
-				if applyStructuredOutputs && !structuredOutputsStarted && (errors.Is(err, context.Canceled) || strings.Contains(err.Error(), "context canceled")) && ctx.Err() == nil {
+				if applyStructuredOutputs && !structuredOutputsStarted && (errors.Is(err, context.Canceled) || strings.Contains(err.Error(), "context canceled")) && c.Request.Context().Err() == nil {
 					// only ignores error if it's a context cancellation due to setting structured outputs
 				} else {
 					slog.Error("chat completion error", "error", err.Error())

server/routes_generate_test.go

@@ -594,6 +594,126 @@ func TestGenerateChat(t *testing.T) {
 			t.Errorf("final tool call mismatch (-got +want):\n%s", diff)
 		}
 	})
+
+	t.Run("structured outputs format propagation", func(t *testing.T) {
+		format := json.RawMessage(`{"type":"object","properties":{"answer":{"type":"string"}}}`)
+		streamRequest := false
+
+		w := createRequest(t, s.CreateHandler, api.CreateRequest{
+			Model:  "test-chat-format",
+			From:   "test",
+			Stream: &streamRequest,
+		})
+		if w.Code != http.StatusOK {
+			t.Fatalf("expected status 200 creating test-chat-format, got %d", w.Code)
+		}
+
+		w = createRequest(t, s.CreateHandler, api.CreateRequest{
+			Model:  "test-chat-format-parser",
+			From:   "test-chat-format",
+			Parser: "passthrough",
+			Stream: &streamRequest,
+		})
+		if w.Code != http.StatusOK {
+			t.Fatalf("expected status 200 creating test-chat-format-parser, got %d", w.Code)
+		}
+
+		t.Run("without parser applies format", func(t *testing.T) {
+			var requests []llm.CompletionRequest
+			mock.CompletionFn = func(ctx context.Context, r llm.CompletionRequest, fn func(llm.CompletionResponse)) error {
+				requests = append(requests, r)
+				fn(llm.CompletionResponse{
+					Content:            `{"answer":"ok"}`,
+					Done:               true,
+					DoneReason:         llm.DoneReasonStop,
+					PromptEvalCount:    1,
+					PromptEvalDuration: 1,
+					EvalCount:          1,
+					EvalDuration:       1,
+				})
+				return nil
+			}
+			t.Cleanup(func() { mock.CompletionFn = nil })
+
+			respRecorder := createRequest(t, s.ChatHandler, api.ChatRequest{
+				Model: "test-chat-format",
+				Messages: []api.Message{
+					{Role: "user", Content: "Give me json"},
+				},
+				Format: format,
+				Stream: &streamRequest,
+			})
+
+			if respRecorder.Code != http.StatusOK {
+				t.Fatalf("expected status 200, got %d", respRecorder.Code)
+			}
+
+			if len(requests) != 1 {
+				t.Fatalf("expected 1 completion call, got %d", len(requests))
+			}
+
+			if diff := cmp.Diff(string(requests[0].Format), string(format)); diff != "" {
+				t.Errorf("format mismatch (-got +want):\n%s", diff)
+			}
+
+			var resp api.ChatResponse
+			if err := json.NewDecoder(respRecorder.Body).Decode(&resp); err != nil {
+				t.Fatal(err)
+			}
+
+			if resp.Message.Content != `{"answer":"ok"}` {
+				t.Errorf("expected structured response, got %q", resp.Message.Content)
+			}
+		})
+
+		t.Run("with parser missing thinking skips format", func(t *testing.T) {
+			var requests []llm.CompletionRequest
+			mock.CompletionFn = func(ctx context.Context, r llm.CompletionRequest, fn func(llm.CompletionResponse)) error {
+				requests = append(requests, r)
+				fn(llm.CompletionResponse{
+					Content:            `{"answer":"ok"}`,
+					Done:               true,
+					DoneReason:         llm.DoneReasonStop,
+					PromptEvalCount:    1,
+					PromptEvalDuration: 1,
+					EvalCount:          1,
+					EvalDuration:       1,
+				})
+				return nil
+			}
+			t.Cleanup(func() { mock.CompletionFn = nil })
+
+			respRecorder := createRequest(t, s.ChatHandler, api.ChatRequest{
+				Model: "test-chat-format-parser",
+				Messages: []api.Message{
+					{Role: "user", Content: "Give me json"},
+				},
+				Format: format,
+				Stream: &streamRequest,
+			})
+
+			if respRecorder.Code != http.StatusOK {
+				t.Fatalf("expected status 200, got %d", respRecorder.Code)
+			}
+
+			if len(requests) != 1 {
+				t.Fatalf("expected 1 completion call, got %d", len(requests))
+			}
+
+			if requests[0].Format != nil {
+				t.Errorf("expected format to be nil when parser is present without thinking")
+			}
+
+			var resp api.ChatResponse
+			if err := json.NewDecoder(respRecorder.Body).Decode(&resp); err != nil {
+				t.Fatal(err)
+			}
+
+			if resp.Message.Content != `{"answer":"ok"}` {
+				t.Errorf("expected structured response passthrough, got %q", resp.Message.Content)
+			}
+		})
+	})
 }
 
 func TestGenerate(t *testing.T) {
@@ -968,6 +1088,7 @@ func TestGenerate(t *testing.T) {
 			t.Errorf("mismatch (-got +want):\n%s", diff)
 		}
 	})
+
 }
 
 func TestChatWithPromptEndingInThinkTag(t *testing.T) {
@@ -1208,7 +1329,7 @@ func TestChatWithPromptEndingInThinkTag(t *testing.T) {
 
 		wg.Add(2)
 
-		format := json.RawMessage([]byte(`{"type":"object","properties":{"answer":{"type":"string"}}}`))
+		format := json.RawMessage(`{"type":"object","properties":{"answer":{"type":"string"}}}`)
 
 		mock.CompletionFn = func(ctx context.Context, r llm.CompletionRequest, fn func(r llm.CompletionResponse)) error {
 			defer wg.Done()
@@ -1311,7 +1432,7 @@ func TestChatWithPromptEndingInThinkTag(t *testing.T) {
 
 		wg.Add(2)
 
-		format := json.RawMessage([]byte(`{"type":"object","properties":{"answer":{"type":"string"}}}`))
+		format := json.RawMessage(`{"type":"object","properties":{"answer":{"type":"string"}}}`)
 
 		mock.CompletionFn = func(ctx context.Context, r llm.CompletionRequest, fn func(r llm.CompletionResponse)) error {
 			defer wg.Done()