fix(opencode): restore free-tier stub tool names to client casing on all response paths

internal/app/anthropic_upstream.go

@@ -137,8 +137,15 @@ func pipeAnthropicStream(ctx context.Context, w http.ResponseWriter, rc io.Reade
 	// observeAnthropicStreamEvent 让 stats 与 message_start/stop 计数正确
 	// 累计——peek 消费过的帧不再二次进 reader.Read() 通道,所以这里必须补
 	// 一次观察。
-	if err := FlushPeekedBytes(w, peek.Consumed); err != nil {
-		return true, err
+	// peek 消费的首帧也要过大小写还原(帧尾常与首个 content_block_start 同行,
+	// 而主循环的还原按行生效),否则首个 tool_use 的 name 会被原样透小写。
+	for _, res := range peek.Consumed {
+		if res.line != "" {
+			res.line = restoreAnthropicStreamLineCase(res.line)
+		}
+		if _, err := io.WriteString(w, res.line); err != nil {
+			return true, err
+		}
 	}
 	sawMessageStop := false
 	observeLine := func(line string) {
@@ -202,7 +209,10 @@ func pipeAnthropicStream(ctx context.Context, w http.ResponseWriter, rc io.Reade
 			pendingErr := result.err
 			if line != "" {
 				observeLine(line)
-				frameBuf.WriteString(line)
+				// 免费层占位工具名大小写还原:仅改写恰为小写占位名的
+				// tool_use name 帧,其余字节原样,保证客户端(大小写敏感)
+				// 不再把 stub 的 read/glob/bash/grep 当成未注册工具。
+				frameBuf.WriteString(restoreAnthropicStreamLineCase(line))
 				// 空行 = 帧边界:整帧一次写出再 Flush。
 				if strings.TrimRight(line, "\r\n") == "" {
 					if err := flushFrame(); err != nil {
@@ -239,6 +249,62 @@ func pipeAnthropicStream(ctx context.Context, w http.ResponseWriter, rc io.Reade
 	}
 }
 
+// restoreAnthropicStreamLineCase 对一行 SSE(含结尾 \n)做免费层占位工具的大小写
+// 还原:仅当它是 "data: " 帧、事件为 content_block_start / content_block_delta 且
+// 携带恰为小写占位名的 tool_use name 时改写该行,其余行(含 content_block_stop、
+// input_json_delta 的 partial_json 文本、非 data 行)原样返回。改写只命中 keep 的
+// 名字段,不动其它字节(换行风格、字段顺序保持上游原样),供 byte-relay 路径在
+// 写给客户端前调用。幂等。
+func restoreAnthropicStreamLineCase(line string) string {
+	payload, ok := strings.CutPrefix(line, "data: ")
+	if !ok {
+		return line
+	}
+	trimmed := strings.TrimRight(payload, "\r\n")
+	if !strings.HasPrefix(trimmed, "{") {
+		return line
+	}
+	var evt map[string]any
+	if json.Unmarshal([]byte(trimmed), &evt) != nil {
+		return line
+	}
+	changed := false
+	if cb, ok := evt["content_block"].(map[string]any); ok {
+		if typ, _ := cb["type"].(string); typ == "tool_use" {
+			if n, _ := cb["name"].(string); n != "" {
+				if r := restoreToolNameCase(n); r != n {
+					cb["name"] = r
+					changed = true
+				}
+			}
+		}
+	}
+	// 兜底:某些上游把起始块放在 event.delta.content_block 而非顶层
+	// content_block;同样覆盖 delta 里偶发出现的 tool_use name。
+	if !changed {
+		if delta, ok := evt["delta"].(map[string]any); ok {
+			if cb, ok := delta["content_block"].(map[string]any); ok {
+				if typ, _ := cb["type"].(string); typ == "tool_use" {
+					if n, _ := cb["name"].(string); n != "" {
+						if r := restoreToolNameCase(n); r != n {
+							cb["name"] = r
+							changed = true
+						}
+					}
+				}
+			}
+		}
+	}
+	if !changed {
+		return line
+	}
+	b, err := json.Marshal(evt)
+	if err != nil {
+		return line
+	}
+	return "data: " + string(b) + "\n"
+}
+
 // observeAnthropicStreamEvent 旁路解析一行 SSE，累计 usage 与流统计。
 func observeAnthropicStreamEvent(stats *logging.StreamStats, fullUsage map[string]any, line string) {
 	payload, ok := strings.CutPrefix(line, "data: ")
@@ -271,6 +337,45 @@ func observeAnthropicStreamEvent(stats *logging.StreamStats, fullUsage map[strin
 	}
 }
 
+// restoreAnthropicBodyToolCase 对一个完整的 Anthropic Messages JSON body 做免费层
+// 占位工具名的大小写还原:遍历 content 数组,把恰为小写占位名(bash/glob/grep/
+// read)的 tool_use block 的 name 还原为规范 PascalCase,assistant / tool_result /
+// 其它块与所有其它字节原样。无法解析或无命中时原样返回(幂等)。供非流式
+// byte-relay 在写给客户端前调用。
+func restoreAnthropicBodyToolCase(body []byte) []byte {
+	var m map[string]any
+	if json.Unmarshal(body, &m) != nil {
+		return body
+	}
+	content, ok := m["content"].([]any)
+	if !ok {
+		return body
+	}
+	changed := false
+	for _, c := range content {
+		block, ok := c.(map[string]any)
+		if !ok {
+			continue
+		}
+		if typ, _ := block["type"].(string); typ != "tool_use" {
+			continue
+		}
+		if n, _ := block["name"].(string); n != "" {
+			if r := restoreToolNameCase(n); r != n {
+				block["name"] = r
+				changed = true
+			}
+		}
+	}
+	if !changed {
+		return body
+	}
+	if b, err := json.Marshal(m); err == nil {
+		return b
+	}
+	return body
+}
+
 // relayAnthropicBuffered 非流式直通与直通路径错误透传（含流式请求下的上游
 // 非 2xx）：buffered 读回上游体，以 application/json + 原状态码保真写回，
 // 并解析 usage 记入 token 统计；上游错误体同时记入去重日志。
@@ -291,7 +396,9 @@ func relayAnthropicBuffered(ctx context.Context, w http.ResponseWriter, rc io.Re
 	}
 	w.Header().Set("Content-Type", "application/json; charset=utf-8")
 	w.WriteHeader(status)
-	w.Write(body)
+	// 非流式直通路径在写回前还原免费层占位工具的小写 tool_use name，
+	// 与流式 byte-relay 的 restoreAnthropicStreamLineCase 对应（幂等）。
+	w.Write(restoreAnthropicBodyToolCase(body))
 
 	if status >= 200 && status < 300 {
 		var raw map[string]any

internal/app/chat_protocol_routing_test.go

@@ -968,10 +968,13 @@ func TestDispatch_ChatToResponsesMemory(t *testing.T) {
 }
 
 func TestResponsesSSEToChatStream_ToolArgumentsShareIndex(t *testing.T) {
+	// 工具名用中性的 Bash(非小写占位名):本用例专测「同 output_index 的参数
+	// 共享」,与工具名大小写无关——小写 "bash" 会被免费层占位大小写还原为
+	// "Bash"(见 restoreToolNameCase),不应作为本用例的夹具值。
 	sse := "event: response.created\ndata: {\"type\":\"response.created\",\"response\":{\"id\":\"resp_7\",\"model\":\"gpt-x\"}}\n\n" +
-		"event: response.output_item.added\ndata: {\"type\":\"response.output_item.added\",\"output_index\":1,\"item\":{\"type\":\"function_call\",\"id\":\"fc_a\",\"call_id\":\"call_a\",\"name\":\"bash\"}}\n\n" +
+		"event: response.output_item.added\ndata: {\"type\":\"response.output_item.added\",\"output_index\":1,\"item\":{\"type\":\"function_call\",\"id\":\"fc_a\",\"call_id\":\"call_a\",\"name\":\"Bash\"}}\n\n" +
 		"event: response.function_call_arguments.delta\ndata: {\"type\":\"response.function_call_arguments.delta\",\"output_index\":1,\"item_id\":\"fc_a\",\"delta\":\"{\\\"cmd\\\":\\\"free -h\\\"}\"}\n\n" +
-		"event: response.output_item.added\ndata: {\"type\":\"response.output_item.added\",\"output_index\":2,\"item\":{\"type\":\"function_call\",\"id\":\"fc_b\",\"call_id\":\"call_b\",\"name\":\"bash\"}}\n\n" +
+		"event: response.output_item.added\ndata: {\"type\":\"response.output_item.added\",\"output_index\":2,\"item\":{\"type\":\"function_call\",\"id\":\"fc_b\",\"call_id\":\"call_b\",\"name\":\"Bash\"}}\n\n" +
 		// no item_id here: matched by output_index
 		"event: response.function_call_arguments.delta\ndata: {\"type\":\"response.function_call_arguments.delta\",\"output_index\":2,\"delta\":\"{\\\"cmd\\\":\\\"uptime\\\"}\"}\n\n" +
 		"event: response.completed\ndata: {\"type\":\"response.completed\",\"response\":{\"id\":\"resp_7\"}}\n\n"
@@ -1017,10 +1020,10 @@ func TestResponsesSSEToChatStream_ToolArgumentsShareIndex(t *testing.T) {
 	if len(names) != 2 {
 		t.Fatalf("want 2 tool calls, got indices %v (arguments %v): %s", names, args, body)
 	}
-	if names[0] != "bash" || args[0] != `{"cmd":"free -h"}` {
+	if names[0] != "Bash" || args[0] != `{"cmd":"free -h"}` {
 		t.Fatalf("tool call 0 = %q %q", names[0], args[0])
 	}
-	if names[1] != "bash" || args[1] != `{"cmd":"uptime"}` {
+	if names[1] != "Bash" || args[1] != `{"cmd":"uptime"}` {
 		t.Fatalf("tool call 1 = %q %q", names[1], args[1])
 	}
 }

internal/app/chat_to_anthropic.go

@@ -194,7 +194,7 @@ func chatMessagesToAnthropic(messages []Message) (string, []map[string]any) {
 			for _, tc := range msg.ToolCalls {
 				input := parseToolCallArguments(tc.Function.Arguments)
 				blocks = append(blocks, map[string]any{
-					"type": "tool_use", "id": tc.ID, "name": tc.Function.Name, "input": input,
+					"type": "tool_use", "id": tc.ID, "name": restoreToolNameCase(tc.Function.Name), "input": input,
 				})
 			}
 			appendBlocks("assistant", blocks)
@@ -896,7 +896,11 @@ func (st *anthropicToChatState) handleLine(line string) {
 			st.toolIndices[idx] = toolIdx
 			tool := &anthropicToolState{}
 			st.toolStates[idx] = tool
-			name, _ := cb["name"].(string)
+			// 免费层小写占位工具名在此还原为客户端注册的规范大小写
+			// (bash/glob/grep/read -> Bash/Glob/Grep/Read),避免 Claude
+			// Code 等大小写敏感客户端报 "No such tool available"。
+			rawName, _ := cb["name"].(string)
+			name := restoreToolNameCase(rawName)
 			id, _ := cb["id"].(string)
 			// 缓存 start 块的 initial input(常见 {});不要立刻 emit 给 chat 端
 			// —— OpenAI 客户端会 concat 所有 arguments 片段,若 start 下发了

internal/app/chat_to_responses_upstream.go

@@ -473,7 +473,7 @@ func aggregateResponsesStreamToChat(body []byte, model string, wantReasoning boo
 				acc.callID = callID
 			}
 			if n, _ := item["name"].(string); n != "" {
-				acc.name = n
+				acc.name = restoreToolNameCase(n)
 			}
 			if args, _ := item["arguments"].(string); args != "" && acc.args == "" {
 				acc.args = args
@@ -1113,7 +1113,7 @@ func (st *responsesToChatState) handleLine(line string) {
 			st.ensureRole()
 			st.emitChunk(map[string]any{"tool_calls": []any{map[string]any{
 				"index": toolIdx, "id": callID, "type": "function",
-				"function": map[string]any{"name": toString(item["name"]), "arguments": ""},
+				"function": map[string]any{"name": restoreToolNameCase(toString(item["name"])), "arguments": ""},
 			}}}, "", nil)
 		}
 	case "response.function_call_arguments.delta", "response.tool_call_arguments.delta":
@@ -1155,7 +1155,7 @@ func (st *responsesToChatState) handleLine(line string) {
 			// 并把 item 上的完整 arguments 作为单段增量发完。
 			if !st.toolAnnounced[toolIdx] {
 				st.toolAnnounced[toolIdx] = true
-				name := toString(item["name"])
+				name := restoreToolNameCase(toString(item["name"]))
 				st.ensureRole()
 				st.emitChunk(map[string]any{"tool_calls": []any{map[string]any{
 					"index": toolIdx, "id": callID, "type": "function",

internal/app/claude.go

@@ -740,7 +740,9 @@ func openAIToClaudeResponse(chatBody []byte, model string, wantReasoning bool) [
 					}
 				case "tool_use":
 					id, _ := blk["id"].(string)
-					name, _ := blk["name"].(string)
+					rawName, _ := blk["name"].(string)
+					// 免费层小写占位工具名还原为规范大小写(见 restoreToolNameCase)。
+					name := restoreToolNameCase(rawName)
 					input := blk["input"]
 					if input == nil {
 						input = map[string]any{}
@@ -783,7 +785,7 @@ func openAIToClaudeResponse(chatBody []byte, model string, wantReasoning bool) [
 				content = append(content, ClaudeContent{
 					Type:  "tool_use",
 					ID:    tc.ID,
-					Name:  tc.Function.Name,
+					Name:  restoreToolNameCase(tc.Function.Name),
 					Input: input,
 				})
 			}
@@ -1496,7 +1498,10 @@ loop:
 													callID = "toolu_" + randomString(12)
 												}
 												fn, _ := tc["function"].(map[string]any)
-												name, _ := fn["name"].(string)
+												rawName, _ := fn["name"].(string)
+												// 免费层小写占位工具名还原为规范大小写
+												// (见 restoreToolNameCase)。
+												name := restoreToolNameCase(rawName)
 												toolCallAccumulator[upstreamIndex] = map[string]string{
 													"id":   callID,
 													"name": name,

internal/app/claude_responses.go

@@ -731,7 +731,9 @@ func responsesOutputToClaudeBlocks(output []any, wantReasoning bool) ([]ClaudeCo
 			if callID == "" {
 				callID, _ = item["id"].(string)
 			}
-			name, _ := item["name"].(string)
+			rawName, _ := item["name"].(string)
+			// 免费层小写占位工具名还原为规范大小写(见 restoreToolNameCase)。
+			name := restoreToolNameCase(rawName)
 			if name == "" {
 				continue
 			}
@@ -829,7 +831,8 @@ func responsesOutputToClaudeBlocks(output []any, wantReasoning bool) ([]ClaudeCo
 		content = append(content, ClaudeContent{Type: "text", Text: joinedText})
 	}
 	for _, tl := range tools {
-		content = append(content, ClaudeContent{Type: "tool_use", ID: tl.id, Name: tl.name, Input: tl.input})
+		// 免费层小写占位工具名还原为规范大小写(见 restoreToolNameCase)。
+		content = append(content, ClaudeContent{Type: "tool_use", ID: tl.id, Name: restoreToolNameCase(tl.name), Input: tl.input})
 	}
 	if len(content) == 0 {
 		content = append(content, ClaudeContent{Type: "text", Text: ""})
@@ -1284,7 +1287,7 @@ func claudeResponsesStreamHandler(ctx context.Context, w http.ResponseWriter, rc
 		emitEvent("content_block_start", map[string]any{
 			"type": "content_block_start", "index": b.claudeIndex,
 			"content_block": map[string]any{
-				"type": "tool_use", "id": b.toolID, "name": b.toolName, "input": map[string]any{},
+				"type": "tool_use", "id": b.toolID, "name": restoreToolNameCase(b.toolName), "input": map[string]any{},
 			},
 		})
 		if _, exists := indexOfToolOrder(toolOrder, b.claudeIndex); !exists {