工具调用优化

internal/adapter/openai/chat_stream_runtime.go

@@ -98,7 +98,7 @@ func (s *chatStreamRuntime) sendDone() {
 func (s *chatStreamRuntime) finalize(finishReason string) {
 	finalThinking := s.thinking.String()
 	finalText := s.text.String()
-	detected := util.ParseToolCalls(finalText, s.toolNames)
+	detected := util.ParseStandaloneToolCalls(finalText, s.toolNames)
 	if len(detected) > 0 && !s.toolCallsDoneEmitted {
 		finishReason = "tool_calls"
 		delta := map[string]any{

internal/adapter/openai/handler_toolcall_test.go

@@ -211,7 +211,7 @@ func TestHandleNonStreamUnknownToolNotIntercepted(t *testing.T) {
 	}
 }
 
-func TestHandleNonStreamEmbeddedToolCallExampleIntercepted(t *testing.T) {
+func TestHandleNonStreamEmbeddedToolCallExampleRemainsText(t *testing.T) {
 	h := &Handler{}
 	resp := makeSSEHTTPResponse(
 		`data: {"p":"response/content","v":"下面是示例："}`,
@@ -229,16 +229,16 @@ func TestHandleNonStreamEmbeddedToolCallExampleIntercepted(t *testing.T) {
 	out := decodeJSONBody(t, rec.Body.String())
 	choices, _ := out["choices"].([]any)
 	choice, _ := choices[0].(map[string]any)
-	if choice["finish_reason"] != "tool_calls" {
-		t.Fatalf("expected finish_reason=tool_calls, got %#v", choice["finish_reason"])
+	if choice["finish_reason"] != "stop" {
+		t.Fatalf("expected finish_reason=stop, got %#v", choice["finish_reason"])
 	}
 	msg, _ := choice["message"].(map[string]any)
-	toolCalls, _ := msg["tool_calls"].([]any)
-	if len(toolCalls) == 0 {
-		t.Fatalf("expected tool_calls field for embedded example: %#v", msg["tool_calls"])
+	if _, ok := msg["tool_calls"]; ok {
+		t.Fatalf("did not expect tool_calls field for embedded example: %#v", msg["tool_calls"])
 	}
-	if msg["content"] != nil {
-		t.Fatalf("expected content nil when tool_calls detected, got %#v", msg["content"])
+	content, _ := msg["content"].(string)
+	if !strings.Contains(content, "下面是示例：") || !strings.Contains(content, "请勿执行。") || !strings.Contains(content, `"tool_calls"`) {
+		t.Fatalf("expected embedded example to remain plain text, got %#v", content)
 	}
 }
 
@@ -513,8 +513,8 @@ func TestHandleStreamToolCallMixedWithPlainTextSegments(t *testing.T) {
 	if !done {
 		t.Fatalf("expected [DONE], body=%s", rec.Body.String())
 	}
-	if !streamHasToolCallsDelta(frames) {
-		t.Fatalf("expected tool_calls delta in mixed prose stream, body=%s", rec.Body.String())
+	if streamHasToolCallsDelta(frames) {
+		t.Fatalf("did not expect tool_calls delta in mixed prose stream, body=%s", rec.Body.String())
 	}
 	content := strings.Builder{}
 	for _, frame := range frames {
@@ -531,15 +531,15 @@ func TestHandleStreamToolCallMixedWithPlainTextSegments(t *testing.T) {
 	if !strings.Contains(got, "下面是示例：") || !strings.Contains(got, "请勿执行。") {
 		t.Fatalf("expected pre/post plain text to pass sieve, got=%q", got)
 	}
-	if strings.Contains(strings.ToLower(got), `"tool_calls"`) {
-		t.Fatalf("expected no raw tool_calls json leak in content, got=%q", got)
+	if !strings.Contains(strings.ToLower(got), `"tool_calls"`) {
+		t.Fatalf("expected embedded tool json to remain text in strict mode, got=%q", got)
 	}
-	if streamFinishReason(frames) != "tool_calls" {
-		t.Fatalf("expected finish_reason=tool_calls for mixed prose, body=%s", rec.Body.String())
+	if streamFinishReason(frames) != "stop" {
+		t.Fatalf("expected finish_reason=stop for mixed prose, body=%s", rec.Body.String())
 	}
 }
 
-func TestHandleStreamToolCallAfterLeadingTextStillIntercepted(t *testing.T) {
+func TestHandleStreamToolCallAfterLeadingTextRemainsText(t *testing.T) {
 	h := &Handler{}
 	resp := makeSSEHTTPResponse(
 		`data: {"p":"response/content","v":"我将调用工具。"}`,
@@ -555,8 +555,8 @@ func TestHandleStreamToolCallAfterLeadingTextStillIntercepted(t *testing.T) {
 	if !done {
 		t.Fatalf("expected [DONE], body=%s", rec.Body.String())
 	}
-	if !streamHasToolCallsDelta(frames) {
-		t.Fatalf("expected tool_calls delta, body=%s", rec.Body.String())
+	if streamHasToolCallsDelta(frames) {
+		t.Fatalf("did not expect tool_calls delta, body=%s", rec.Body.String())
 	}
 	content := strings.Builder{}
 	for _, frame := range frames {
@@ -573,15 +573,15 @@ func TestHandleStreamToolCallAfterLeadingTextStillIntercepted(t *testing.T) {
 	if !strings.Contains(got, "我将调用工具。") {
 		t.Fatalf("expected leading text to keep streaming, got=%q", got)
 	}
-	if strings.Contains(strings.ToLower(got), "tool_calls") {
-		t.Fatalf("unexpected raw tool json leak, got=%q", got)
+	if !strings.Contains(strings.ToLower(got), "tool_calls") {
+		t.Fatalf("expected tool_calls example text preserved, got=%q", got)
 	}
-	if streamFinishReason(frames) != "tool_calls" {
-		t.Fatalf("expected finish_reason=tool_calls, body=%s", rec.Body.String())
+	if streamFinishReason(frames) != "stop" {
+		t.Fatalf("expected finish_reason=stop, body=%s", rec.Body.String())
 	}
 }
 
-func TestHandleStreamToolCallWithSameChunkTrailingTextStillIntercepted(t *testing.T) {
+func TestHandleStreamToolCallWithSameChunkTrailingTextRemainsText(t *testing.T) {
 	h := &Handler{}
 	resp := makeSSEHTTPResponse(
 		`data: {"p":"response/content","v":"{\"tool_calls\":[{\"name\":\"search\",\"input\":{\"q\":\"go\"}}]}接下来我会继续说明。"}`,
@@ -596,8 +596,8 @@ func TestHandleStreamToolCallWithSameChunkTrailingTextStillIntercepted(t *testin
 	if !done {
 		t.Fatalf("expected [DONE], body=%s", rec.Body.String())
 	}
-	if !streamHasToolCallsDelta(frames) {
-		t.Fatalf("expected tool_calls delta, body=%s", rec.Body.String())
+	if streamHasToolCallsDelta(frames) {
+		t.Fatalf("did not expect tool_calls delta, body=%s", rec.Body.String())
 	}
 	content := strings.Builder{}
 	for _, frame := range frames {
@@ -614,15 +614,15 @@ func TestHandleStreamToolCallWithSameChunkTrailingTextStillIntercepted(t *testin
 	if !strings.Contains(got, "接下来我会继续说明。") {
 		t.Fatalf("expected trailing plain text to be preserved, got=%q", got)
 	}
-	if strings.Contains(strings.ToLower(got), "tool_calls") {
-		t.Fatalf("unexpected raw tool json leak, got=%q", got)
+	if !strings.Contains(strings.ToLower(got), "tool_calls") {
+		t.Fatalf("expected tool_calls example text preserved, got=%q", got)
 	}
-	if streamFinishReason(frames) != "tool_calls" {
-		t.Fatalf("expected finish_reason=tool_calls, body=%s", rec.Body.String())
+	if streamFinishReason(frames) != "stop" {
+		t.Fatalf("expected finish_reason=stop, body=%s", rec.Body.String())
 	}
 }
 
-func TestHandleStreamToolCallKeyAppearsLateStillNoPrefixLeak(t *testing.T) {
+func TestHandleStreamToolCallKeyAppearsLateRemainsText(t *testing.T) {
 	h := &Handler{}
 	spaces := strings.Repeat(" ", 200)
 	resp := makeSSEHTTPResponse(
@@ -640,11 +640,8 @@ func TestHandleStreamToolCallKeyAppearsLateStillNoPrefixLeak(t *testing.T) {
 	if !done {
 		t.Fatalf("expected [DONE], body=%s", rec.Body.String())
 	}
-	if !streamHasToolCallsDelta(frames) {
-		t.Fatalf("expected tool_calls delta, body=%s", rec.Body.String())
-	}
-	if streamHasRawToolJSONContent(frames) {
-		t.Fatalf("raw tool_calls JSON leaked in content delta: %s", rec.Body.String())
+	if streamHasToolCallsDelta(frames) {
+		t.Fatalf("did not expect tool_calls delta, body=%s", rec.Body.String())
 	}
 	content := strings.Builder{}
 	for _, frame := range frames {
@@ -658,14 +655,14 @@ func TestHandleStreamToolCallKeyAppearsLateStillNoPrefixLeak(t *testing.T) {
 		}
 	}
 	got := content.String()
-	if strings.Contains(got, "{") {
-		t.Fatalf("unexpected suspicious prefix leak in content: %q", got)
+	if !strings.Contains(strings.ToLower(got), "tool_calls") || !strings.Contains(got, "{") {
+		t.Fatalf("expected embedded tool json to remain in text, got=%q", got)
 	}
 	if !strings.Contains(got, "后置正文C。") {
 		t.Fatalf("expected stream to continue after tool json convergence, got=%q", got)
 	}
-	if streamFinishReason(frames) != "tool_calls" {
-		t.Fatalf("expected finish_reason=tool_calls, body=%s", rec.Body.String())
+	if streamFinishReason(frames) != "stop" {
+		t.Fatalf("expected finish_reason=stop, body=%s", rec.Body.String())
 	}
 }
 
@@ -743,7 +740,7 @@ func TestHandleStreamIncompleteCapturedToolJSONFlushesAsTextOnFinalize(t *testin
 	}
 }
 
-func TestHandleStreamToolCallArgumentsEmitIncrementally(t *testing.T) {
+func TestHandleStreamToolCallArgumentsEmitAsSingleCompletedChunk(t *testing.T) {
 	h := &Handler{}
 	resp := makeSSEHTTPResponse(
 		`data: {"p":"response/content","v":"{\"tool_calls\":[{\"name\":\"search\",\"input\":{\"q\":\"go"}`,
@@ -766,8 +763,8 @@ func TestHandleStreamToolCallArgumentsEmitIncrementally(t *testing.T) {
 		t.Fatalf("raw tool_calls JSON leaked in content delta: %s", rec.Body.String())
 	}
 	argChunks := streamToolCallArgumentChunks(frames)
-	if len(argChunks) < 2 {
-		t.Fatalf("expected incremental arguments chunks, got=%v body=%s", argChunks, rec.Body.String())
+	if len(argChunks) == 0 {
+		t.Fatalf("expected tool call arguments chunk, got=%v body=%s", argChunks, rec.Body.String())
 	}
 	joined := strings.Join(argChunks, "")
 	if !strings.Contains(joined, `"q":"golang"`) || !strings.Contains(joined, `"page":1`) {

internal/adapter/openai/message_normalize.go

@@ -3,7 +3,6 @@ package openai
 import (
 	"encoding/json"
 	"fmt"
-	"io"
 	"strings"
 
 	"ds2api/internal/config"
@@ -175,30 +174,11 @@ func normalizeToolArgumentString(raw string) string {
 	if trimmed == "" {
 		return ""
 	}
-	if !looksLikeConcatenatedJSON(trimmed) {
-		return trimmed
+	if looksLikeConcatenatedJSON(trimmed) {
+		// Keep original payload to avoid silent argument rewrites.
+		return raw
 	}
-	dec := json.NewDecoder(strings.NewReader(trimmed))
-	values := make([]any, 0, 2)
-	for {
-		var v any
-		if err := dec.Decode(&v); err != nil {
-			if err == io.EOF {
-				break
-			}
-			return trimmed
-		}
-		values = append(values, v)
-	}
-	if len(values) < 2 {
-		return trimmed
-	}
-	last := values[len(values)-1]
-	b, err := json.Marshal(last)
-	if err != nil || len(b) == 0 {
-		return trimmed
-	}
-	return string(b)
+	return trimmed
 }
 
 func marshalToPromptString(v any) string {

internal/adapter/openai/message_normalize_test.go

@@ -168,7 +168,7 @@ func TestNormalizeOpenAIMessagesForPrompt_AssistantMultipleToolCallsRemainSepara
 	}
 }
 
-func TestNormalizeOpenAIMessagesForPrompt_RepairsConcatenatedToolArguments(t *testing.T) {
+func TestNormalizeOpenAIMessagesForPrompt_PreservesConcatenatedToolArguments(t *testing.T) {
 	raw := []any{
 		map[string]any{
 			"role": "assistant",
@@ -189,10 +189,7 @@ func TestNormalizeOpenAIMessagesForPrompt_RepairsConcatenatedToolArguments(t *te
 		t.Fatalf("expected one normalized message, got %d", len(normalized))
 	}
 	content, _ := normalized[0]["content"].(string)
-	if !strings.Contains(content, `function.arguments: {"query":"测试工具调用"}`) {
-		t.Fatalf("expected repaired arguments in tool history, got %q", content)
-	}
-	if strings.Contains(content, `{}{"query":"测试工具调用"}`) {
-		t.Fatalf("expected concatenated JSON to be repaired, got %q", content)
+	if !strings.Contains(content, `function.arguments: {}{"query":"测试工具调用"}`) {
+		t.Fatalf("expected original concatenated arguments in tool history, got %q", content)
 	}
 }

internal/adapter/openai/responses_embeddings_test.go

@@ -135,7 +135,7 @@ func TestNormalizeResponsesInputAsMessagesFunctionCallItem(t *testing.T) {
 	}
 }
 
-func TestNormalizeResponsesInputAsMessagesFunctionCallItemRepairsConcatenatedArguments(t *testing.T) {
+func TestNormalizeResponsesInputAsMessagesFunctionCallItemPreservesConcatenatedArguments(t *testing.T) {
 	msgs := normalizeResponsesInputAsMessages([]any{
 		map[string]any{
 			"type":      "function_call",
@@ -151,8 +151,8 @@ func TestNormalizeResponsesInputAsMessagesFunctionCallItemRepairsConcatenatedArg
 	toolCalls, _ := m["tool_calls"].([]any)
 	call, _ := toolCalls[0].(map[string]any)
 	fn, _ := call["function"].(map[string]any)
-	if fn["arguments"] != `{"q":"golang"}` {
-		t.Fatalf("expected concatenated call arguments repaired, got %#v", fn["arguments"])
+	if fn["arguments"] != `{}{"q":"golang"}` {
+		t.Fatalf("expected original concatenated call arguments preserved, got %#v", fn["arguments"])
 	}
 }
 

internal/adapter/openai/responses_stream_test.go

@@ -99,9 +99,6 @@ func TestHandleResponsesStreamUsesOfficialOutputItemEvents(t *testing.T) {
 	if !strings.Contains(body, "event: response.output_item.done") {
 		t.Fatalf("expected response.output_item.done event, body=%s", body)
 	}
-	if !strings.Contains(body, "event: response.function_call_arguments.delta") {
-		t.Fatalf("expected response.function_call_arguments.delta event, body=%s", body)
-	}
 	if !strings.Contains(body, "event: response.function_call_arguments.done") {
 		t.Fatalf("expected response.function_call_arguments.done event, body=%s", body)
 	}
@@ -360,7 +357,7 @@ func TestHandleResponsesStreamToolChoiceNoneRejectsFunctionCall(t *testing.T) {
 	}
 }
 
-func TestHandleResponsesStreamMalformedToolJSONClosesInProgressFunctionItem(t *testing.T) {
+func TestHandleResponsesStreamMalformedToolJSONFallsBackToText(t *testing.T) {
 	h := &Handler{}
 	req := httptest.NewRequest(http.MethodPost, "/v1/responses", nil)
 	rec := httptest.NewRecorder()
@@ -373,7 +370,7 @@ func TestHandleResponsesStreamMalformedToolJSONClosesInProgressFunctionItem(t *t
 		return "data: " + string(b) + "\n"
 	}
 
-	// invalid JSON (NaN) can still trigger incremental tool deltas before final parse rejects it
+	// invalid JSON (NaN) should remain plain text in strict mode.
 	streamBody := sseLine(`{"tool_calls":[{"name":"read_file","input":{"path":"README.MD"},"x":NaN}]}`) + "data: [DONE]\n"
 	resp := &http.Response{
 		StatusCode: http.StatusOK,
@@ -382,14 +379,11 @@ func TestHandleResponsesStreamMalformedToolJSONClosesInProgressFunctionItem(t *t
 
 	h.handleResponsesStream(rec, req, resp, "owner-a", "resp_test", "deepseek-chat", "prompt", false, false, []string{"read_file"}, util.DefaultToolChoicePolicy(), "")
 	body := rec.Body.String()
-	if !strings.Contains(body, "event: response.function_call_arguments.delta") {
-		t.Fatalf("expected response.function_call_arguments.delta event for malformed payload, body=%s", body)
+	if strings.Contains(body, "event: response.function_call_arguments.delta") || strings.Contains(body, "event: response.function_call_arguments.done") {
+		t.Fatalf("did not expect function_call events for malformed payload in strict mode, body=%s", body)
 	}
-	if !strings.Contains(body, "event: response.function_call_arguments.done") {
-		t.Fatalf("expected runtime to close in-progress function_call with done event, body=%s", body)
-	}
-	if !strings.Contains(body, "event: response.output_item.done") {
-		t.Fatalf("expected runtime to close function output item, body=%s", body)
+	if !strings.Contains(body, "event: response.output_text.delta") {
+		t.Fatalf("expected response.output_text.delta for malformed payload, body=%s", body)
 	}
 	if !strings.Contains(body, "event: response.completed") {
 		t.Fatalf("expected response.completed event, body=%s", body)

internal/adapter/openai/stream_status_test.go

@@ -167,19 +167,15 @@ func TestResponsesNonStreamMixedProseToolPayloadHandlerPath(t *testing.T) {
 		t.Fatalf("decode response failed: %v body=%s", err, rec.Body.String())
 	}
 	outputText, _ := out["output_text"].(string)
-	if outputText != "" {
-		t.Fatalf("expected output_text hidden for tool call payload, got %q", outputText)
+	if outputText == "" {
+		t.Fatalf("expected output_text preserved for mixed prose payload")
 	}
 	output, _ := out["output"].([]any)
-	hasFunctionCall := false
-	for _, item := range output {
-		m, _ := item.(map[string]any)
-		if m != nil && m["type"] == "function_call" {
-			hasFunctionCall = true
-			break
-		}
+	if len(output) != 1 {
+		t.Fatalf("expected one output item, got %#v", output)
 	}
-	if !hasFunctionCall {
-		t.Fatalf("expected function_call output item, got %#v", output)
+	first, _ := output[0].(map[string]any)
+	if first["type"] != "message" {
+		t.Fatalf("expected message output item, got %#v", output)
 	}
 }

internal/adapter/openai/tool_sieve_core.go

@@ -14,6 +14,21 @@ func processToolSieveChunk(state *toolStreamSieveState, chunk string, toolNames
 		state.pending.WriteString(chunk)
 	}
 	events := make([]toolStreamEvent, 0, 2)
+	if len(state.pendingToolCalls) > 0 {
+		pending := state.pending.String()
+		if strings.TrimSpace(pending) != "" {
+			content := state.pendingToolRaw + pending
+			state.pending.Reset()
+			state.pendingToolRaw = ""
+			state.pendingToolCalls = nil
+			state.noteText(content)
+			events = append(events, toolStreamEvent{Content: content})
+		} else {
+			// Wait for either more non-whitespace content (demote to plain text)
+			// or stream flush (promote to executable tool calls).
+			return events
+		}
+	}
 
 	for {
 		if state.capturing {
@@ -21,23 +36,23 @@ func processToolSieveChunk(state *toolStreamSieveState, chunk string, toolNames
 				state.capture.WriteString(state.pending.String())
 				state.pending.Reset()
 			}
-			if deltas := buildIncrementalToolDeltas(state); len(deltas) > 0 {
-				events = append(events, toolStreamEvent{ToolCallDeltas: deltas})
-			}
 			prefix, calls, suffix, ready := consumeToolCapture(state, toolNames)
 			if !ready {
 				break
 			}
+			captured := state.capture.String()
 			state.capture.Reset()
 			state.capturing = false
 			state.resetIncrementalToolState()
+			if len(calls) > 0 {
+				state.pendingToolRaw = captured
+				state.pendingToolCalls = calls
+				continue
+			}
 			if prefix != "" {
 				state.noteText(prefix)
 				events = append(events, toolStreamEvent{Content: prefix})
 			}
-			if len(calls) > 0 {
-				events = append(events, toolStreamEvent{ToolCalls: calls})
-			}
 			if suffix != "" {
 				state.pending.WriteString(suffix)
 			}
@@ -80,6 +95,11 @@ func flushToolSieve(state *toolStreamSieveState, toolNames []string) []toolStrea
 		return nil
 	}
 	events := processToolSieveChunk(state, "", toolNames)
+	if len(state.pendingToolCalls) > 0 {
+		events = append(events, toolStreamEvent{ToolCalls: state.pendingToolCalls})
+		state.pendingToolRaw = ""
+		state.pendingToolCalls = nil
+	}
 	if state.capturing {
 		consumedPrefix, consumedCalls, consumedSuffix, ready := consumeToolCapture(state, toolNames)
 		if ready {
@@ -191,6 +211,11 @@ func consumeToolCapture(state *toolStreamSieveState, toolNames []string) (prefix
 	if insideCodeFence(state.recentTextTail + prefixPart) {
 		return captured, nil, "", true
 	}
+	// Strict mode: only standalone tool payloads are executable. If the
+	// payload is wrapped by non-whitespace prose, keep it as plain text.
+	if strings.TrimSpace(state.recentTextTail) != "" || strings.TrimSpace(prefixPart) != "" || strings.TrimSpace(suffixPart) != "" {
+		return captured, nil, "", true
+	}
 	parsed := util.ParseStandaloneToolCallsDetailed(obj, toolNames)
 	if len(parsed.Calls) == 0 {
 		if parsed.SawToolCallSyntax && parsed.RejectedByPolicy {

internal/adapter/openai/tool_sieve_state.go

@@ -7,17 +7,19 @@ import (
 )
 
 type toolStreamSieveState struct {
-	pending        strings.Builder
-	capture        strings.Builder
-	capturing      bool
-	recentTextTail string
-	disableDeltas  bool
-	toolNameSent   bool
-	toolName       string
-	toolArgsStart  int
-	toolArgsSent   int
-	toolArgsString bool
-	toolArgsDone   bool
+	pending          strings.Builder
+	capture          strings.Builder
+	capturing        bool
+	recentTextTail   string
+	pendingToolRaw   string
+	pendingToolCalls []util.ParsedToolCall
+	disableDeltas    bool
+	toolNameSent     bool
+	toolName         string
+	toolArgsStart    int
+	toolArgsSent     int
+	toolArgsString   bool
+	toolArgsDone     bool
 }
 
 type toolStreamEvent struct {

internal/format/openai/render_chat.go

@@ -8,7 +8,7 @@ import (
 )
 
 func BuildChatCompletion(completionID, model, finalPrompt, finalThinking, finalText string, toolNames []string) map[string]any {
-	detected := util.ParseToolCalls(finalText, toolNames)
+	detected := util.ParseStandaloneToolCalls(finalText, toolNames)
 	finishReason := "stop"
 	messageObj := map[string]any{"role": "assistant", "content": finalText}
 	if strings.TrimSpace(finalThinking) != "" {

internal/format/openai/render_responses.go

@@ -11,12 +11,9 @@ import (
 )
 
 func BuildResponseObject(responseID, model, finalPrompt, finalThinking, finalText string, toolNames []string) map[string]any {
-	// Align responses tool-call semantics with chat/completions:
-	// mixed prose + tool_call payloads should still be interpreted as tool calls.
-	detected := util.ParseToolCalls(finalText, toolNames)
-	if len(detected) == 0 && strings.TrimSpace(finalThinking) != "" {
-		detected = util.ParseToolCalls(finalThinking, toolNames)
-	}
+	// Strict mode: only standalone, structured tool-call payloads are treated
+	// as executable tool calls.
+	detected := util.ParseStandaloneToolCalls(finalText, toolNames)
 	exposedOutputText := finalText
 	output := make([]any, 0, 2)
 	if len(detected) > 0 {

internal/format/openai/render_test.go

@@ -45,7 +45,7 @@ func TestBuildResponseObjectToolCallsFollowChatShape(t *testing.T) {
 	}
 }
 
-func TestBuildResponseObjectTreatsMixedProseToolPayloadAsToolCall(t *testing.T) {
+func TestBuildResponseObjectTreatsMixedProseToolPayloadAsText(t *testing.T) {
 	obj := BuildResponseObject(
 		"resp_test",
 		"gpt-4o",
@@ -56,17 +56,16 @@ func TestBuildResponseObjectTreatsMixedProseToolPayloadAsToolCall(t *testing.T)
 	)
 
 	outputText, _ := obj["output_text"].(string)
-	if outputText != "" {
-		t.Fatalf("expected output_text hidden once tool calls are detected, got %q", outputText)
+	if outputText == "" {
+		t.Fatalf("expected output_text preserved for mixed prose payload")
 	}
-
 	output, _ := obj["output"].([]any)
 	if len(output) != 1 {
-		t.Fatalf("expected function_call output only, got %#v", obj["output"])
+		t.Fatalf("expected one message output item, got %#v", obj["output"])
 	}
 	first, _ := output[0].(map[string]any)
-	if first["type"] != "function_call" {
-		t.Fatalf("expected first output type function_call, got %#v", first["type"])
+	if first["type"] != "message" {
+		t.Fatalf("expected message output type, got %#v", first["type"])
 	}
 }
 
@@ -127,7 +126,7 @@ func TestBuildResponseObjectReasoningOnlyFallsBackToOutputText(t *testing.T) {
 	}
 }
 
-func TestBuildResponseObjectDetectsToolCallFromThinkingChannel(t *testing.T) {
+func TestBuildResponseObjectIgnoresToolCallFromThinkingChannel(t *testing.T) {
 	obj := BuildResponseObject(
 		"resp_test",
 		"gpt-4o",
@@ -139,10 +138,10 @@ func TestBuildResponseObjectDetectsToolCallFromThinkingChannel(t *testing.T) {
 
 	output, _ := obj["output"].([]any)
 	if len(output) != 1 {
-		t.Fatalf("expected function_call output only, got %#v", obj["output"])
+		t.Fatalf("expected one message output item, got %#v", obj["output"])
 	}
 	first, _ := output[0].(map[string]any)
-	if first["type"] != "function_call" {
-		t.Fatalf("expected output function_call, got %#v", first["type"])
+	if first["type"] != "message" {
+		t.Fatalf("expected output message, got %#v", first["type"])
 	}
 }

internal/server/router.go

@@ -57,16 +57,20 @@ func NewApp() *App {
 	r.Use(cors)
 	r.Use(timeout(0))
 
-	r.Get("/healthz", func(w http.ResponseWriter, _ *http.Request) {
+	healthzHandler := func(w http.ResponseWriter, _ *http.Request) {
 		w.Header().Set("Content-Type", "application/json")
 		w.WriteHeader(http.StatusOK)
 		_, _ = w.Write([]byte(`{"status":"ok"}`))
-	})
-	r.Get("/readyz", func(w http.ResponseWriter, _ *http.Request) {
+	}
+	readyzHandler := func(w http.ResponseWriter, _ *http.Request) {
 		w.Header().Set("Content-Type", "application/json")
 		w.WriteHeader(http.StatusOK)
 		_, _ = w.Write([]byte(`{"status":"ready"}`))
-	})
+	}
+	r.Get("/healthz", healthzHandler)
+	r.Head("/healthz", healthzHandler)
+	r.Get("/readyz", readyzHandler)
+	r.Head("/readyz", readyzHandler)
 	openai.RegisterRoutes(r, openaiHandler)
 	claude.RegisterRoutes(r, claudeHandler)
 	gemini.RegisterRoutes(r, geminiHandler)

internal/server/router_health_test.go

@@ -0,0 +1,20 @@
+package server
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestHealthEndpointsSupportHEAD(t *testing.T) {
+	app := NewApp()
+
+	for _, path := range []string{"/healthz", "/readyz"} {
+		req := httptest.NewRequest(http.MethodHead, path, nil)
+		rec := httptest.NewRecorder()
+		app.Router.ServeHTTP(rec, req)
+		if rec.Code != http.StatusOK {
+			t.Fatalf("expected %s HEAD status 200, got %d", path, rec.Code)
+		}
+	}
+}

internal/testsuite/runner_cases_openai.go

@@ -17,6 +17,12 @@ func (r *Runner) caseHealthz(ctx context.Context, cc *caseContext) error {
 	var m map[string]any
 	_ = json.Unmarshal(resp.Body, &m)
 	cc.assert("status_ok", asString(m["status"]) == "ok", fmt.Sprintf("body=%s", string(resp.Body)))
+
+	headResp, headErr := cc.request(ctx, requestSpec{Method: http.MethodHead, Path: "/healthz", Retryable: true})
+	if headErr != nil {
+		return headErr
+	}
+	cc.assert("head_status_200", headResp.StatusCode == http.StatusOK, fmt.Sprintf("status=%d", headResp.StatusCode))
 	return nil
 }
 
@@ -29,6 +35,12 @@ func (r *Runner) caseReadyz(ctx context.Context, cc *caseContext) error {
 	var m map[string]any
 	_ = json.Unmarshal(resp.Body, &m)
 	cc.assert("status_ready", asString(m["status"]) == "ready", fmt.Sprintf("body=%s", string(resp.Body)))
+
+	headResp, headErr := cc.request(ctx, requestSpec{Method: http.MethodHead, Path: "/readyz", Retryable: true})
+	if headErr != nil {
+		return headErr
+	}
+	cc.assert("head_status_200", headResp.StatusCode == http.StatusOK, fmt.Sprintf("status=%d", headResp.StatusCode))
 	return nil
 }