fix(tools): MCP/自定义工具输出统一走 Capture 截断，修复 mcp 截断不生效 (#176)

mcphttp/client.go

@@ -292,7 +292,7 @@ func (c *Client) wrap(rt remoteTool) actool.CoreTool {
 		Permissions: func(context.Context, json.RawMessage, permission.Context) permission.Decision {
 			return permission.AskUser("call MCP tool " + full + "?")
 		},
-		Run: func(ctx context.Context, in json.RawMessage, _ *actool.ToolContext) (actool.Result, error) {
+		Run: func(ctx context.Context, in json.RawMessage, tc *actool.ToolContext) (actool.Result, error) {
 			var args any
 			if len(in) > 0 {
 				_ = json.Unmarshal(in, &args)
@@ -315,7 +315,10 @@ func (c *Client) wrap(rt remoteTool) actool.CoreTool {
 			for _, blk := range res.Content {
 				text += blk.Text
 			}
-			return actool.Result{Content: []llm.ContentBlock{llm.TextBlock(text)}, IsError: res.IsError}, nil
+			// 与内置/自定义工具一致：超长输出走 Capture——按会话 MaxOutputChars（默认
+			// 30000）截断，配了 ToolOutputDir 时全量溢写到磁盘只留 head + 指针，避免大
+			// MCP 结果整段灌爆上下文。
+			return actool.Result{Content: []llm.ContentBlock{llm.TextBlock(actool.Capture(tc, text))}, IsError: res.IsError}, nil
 		},
 	})
 }

server/customtool.go

@@ -17,9 +17,9 @@ import (
 	"strings"
 	"time"
 
+	"github.com/Autumn-27/artex/db"
 	"github.com/Autumn-27/norma/permission"
 	actool "github.com/Autumn-27/norma/tool"
-	"github.com/Autumn-27/artex/db"
 )
 
 // 本文件实现自定义工具执行器(docs/自定义工具设计.md)。system=false 的 tools 行按
@@ -167,7 +167,7 @@ func (s *Server) pgTestCustomTool(w http.ResponseWriter, r *http.Request) {
 	case "script":
 		res, _ = s.runScriptTool(ctx, "test", req.Exec, params, tc)
 	case "http":
-		res, _ = s.runHTTPTool(ctx, req.Exec, params)
+		res, _ = s.runHTTPTool(ctx, req.Exec, params, tc)
 	case "shell":
 		writeErr(w, 400, "shell 类型工具是 bash 环境声明，无可执行内容")
 		return
@@ -279,7 +279,7 @@ func (s *Server) buildCustomTool(t *db.Tool) actool.CoreTool {
 		case "script":
 			return s.runScriptTool(ctx, key, execRaw, params, tc)
 		case "http":
-			return s.runHTTPTool(ctx, execRaw, params)
+			return s.runHTTPTool(ctx, execRaw, params, tc)
 		default:
 			return actool.Errorf("未知自定义工具类型: " + kind), nil
 		}
@@ -370,7 +370,7 @@ func (s *Server) runScriptTool(ctx context.Context, key string, execRaw json.Raw
 	if err != nil {
 		return actool.Errorf(err.Error()), nil
 	}
-	return actool.Text(clipOutput(body, tc)), nil
+	return actool.Text(actool.Capture(tc, body)), nil
 }
 
 // execPython writes the code to a temp .py under workDir/.tools, runs it via interp
@@ -417,7 +417,7 @@ func execPython(ctx context.Context, interp, key, code string, params map[string
 
 // ---------- http:原生请求 + 代理 ----------
 
-func (s *Server) runHTTPTool(ctx context.Context, execRaw json.RawMessage, params map[string]any) (actool.Result, error) {
+func (s *Server) runHTTPTool(ctx context.Context, execRaw json.RawMessage, params map[string]any, tc *actool.ToolContext) (actool.Result, error) {
 	var spec httpExec
 	_ = json.Unmarshal(execRaw, &spec)
 	method := strings.ToUpper(strings.TrimSpace(spec.Method))
@@ -453,7 +453,7 @@ func (s *Server) runHTTPTool(ctx context.Context, execRaw json.RawMessage, param
 	respBody, _ := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
 	out := map[string]any{"status": resp.StatusCode, "body": string(respBody)}
 	b, _ := json.Marshal(out)
-	return actool.Text(clipOutput(string(b), nil)), nil
+	return actool.Text(actool.Capture(tc, string(b))), nil
 }
 
 // httpProxyTransport builds a Transport for the http tool's proxy config, or nil
@@ -529,15 +529,3 @@ func scalarStr(v any) (string, bool) {
 		return "", false
 	}
 }
-
-// clipOutput caps output to the session's MaxOutputChars (or a default).
-func clipOutput(s string, tc *actool.ToolContext) string {
-	max := 6000
-	if tc != nil && tc.MaxOutputChars > 0 {
-		max = tc.MaxOutputChars
-	}
-	if len(s) <= max {
-		return s
-	}
-	return s[:max] + fmt.Sprintf("\n... [截断，共 %d 字节] ...", len(s))
-}

server/customtool_test.go

@@ -129,7 +129,7 @@ func TestRunHTTPTool(t *testing.T) {
 		"body":    `{"flag":"{flag}"}`,
 	})
 	res, err := (&Server{}).runHTTPTool(context.Background(), execRaw,
-		map[string]any{"flag": "CTF{x}", "token": "sekret"})
+		map[string]any{"flag": "CTF{x}", "token": "sekret"}, nil)
 	if err != nil {
 		t.Fatalf("runHTTPTool: %v", err)
 	}
@@ -165,14 +165,23 @@ func TestDetectPython(t *testing.T) {
 	}
 }
 
-func TestClipOutput(t *testing.T) {
-	long := strings.Repeat("x", 7000)
-	got := clipOutput(long, nil)
-	if len(got) >= 7000 || !strings.Contains(got, "截断") {
-		t.Fatalf("clipOutput should truncate long output, got len %d", len(got))
+// The http tool must truncate an oversized response through norma's Capture, the
+// same valve every other tool uses — a session with no OutputDir falls back to a
+// head+tail cut, so a body far past the default cap comes back shortened.
+func TestHTTPToolTruncatesLargeBody(t *testing.T) {
+	big := strings.Repeat("x", 40000) // past Capture's 30000 default
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, _ = w.Write([]byte(big))
+	}))
+	defer srv.Close()
+
+	execRaw, _ := json.Marshal(map[string]any{"method": "GET", "url": srv.URL})
+	res, err := (&Server{}).runHTTPTool(context.Background(), execRaw, map[string]any{}, nil)
+	if err != nil {
+		t.Fatalf("runHTTPTool: %v", err)
 	}
-	short := "ok"
-	if clipOutput(short, nil) != short {
-		t.Fatal("clipOutput should pass short output through")
+	out := res.Flatten()
+	if len(out) >= 40000 {
+		t.Fatalf("oversized http body was not truncated: len=%d", len(out))
 	}
 }