Point the nested agent-native pin at the delegation template update

Why: Dev-level pin consistency (scripts/check-pins.sh hard-errors on nested
vs Dev-level drift); agent-native main advanced to 37c5e6f (Request
OutputFormat/Tools, agent-native #40).

Evidence: adapters/native and root suites green against 37c5e6f (SELF);
CI authoritative (GATE).

Impact: nested deps/agent-native 1ac21c6 -> 37c5e6f; no squad source
changes.

Refs: Q3 plan WP3/WP6; Dev card .task/feature-agent-stack-q3.md

adapters/a2a/card.go

@@ -0,0 +1,179 @@
+// Package a2a 把小队接入 A2A（Agent2Agent）1.0 互通面（Q3 WP4）：
+//   - 发布侧：BuildCard 从角色注册表与蓝图注册表渲染 Agent Card（描述本
+//     团队能力），CardHandler 以 JSON 服务（挂载在
+//     /.well-known/agent-card.json）；
+//   - 消费侧：FetchCard 发现远端 Agent Card（fail-closed 校验必备字段），
+//     Executor 实现 squad.Executor——message/send 发起任务，tasks/get 轮询
+//     A2A 任务状态机（submitted/working/input-required → completed/failed/
+//     canceled），终态映射 ExecResult：completed 的 artifacts（TextPart/
+//     FilePart）落成 patches/目标文件；failed/canceled/input-required 一律
+//     Success=false（跨进程挂起不在本适配面内，fail-closed 交引擎重试/降级
+//     语义处理）。
+//
+// 传输为 JSON-RPC 2.0 over HTTP（A2A 1.0 形态）；不引入协议之外的依赖。
+package a2a
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strings"
+
+	"agent-squad/squad"
+)
+
+// ProtocolVersion 对齐的 A2A 协议版本。
+const ProtocolVersion = "1.0"
+
+// WellKnownPath 是 Agent Card 的发现路径（A2A 1.0）。
+const WellKnownPath = "/.well-known/agent-card.json"
+
+// AgentCard 是 A2A 1.0 Agent Card（发布与消费共用形态）。
+type AgentCard struct {
+	ProtocolVersion string `json:"protocolVersion"`
+	Name            string `json:"name"`
+	Description     string `json:"description,omitempty"`
+	// URL 是 JSON-RPC 服务端点（消费侧据此发 message/send）。
+	URL         string   `json:"url"`
+	Version     string   `json:"version"`
+	Capabilities CardCapabilities `json:"capabilities"`
+	DefaultInputModes  []string `json:"defaultInputModes,omitempty"`
+	DefaultOutputModes []string `json:"defaultOutputModes,omitempty"`
+	Skills      []AgentSkill `json:"skills,omitempty"`
+}
+
+// CardCapabilities 能力声明（本适配面：非流式、无推送、无状态历史）。
+type CardCapabilities struct {
+	Streaming              bool `json:"streaming"`
+	PushNotifications      bool `json:"pushNotifications"`
+	StateTransitionHistory bool `json:"stateTransitionHistory"`
+}
+
+// AgentSkill 是一项可被远端调用的能力。
+type AgentSkill struct {
+	ID          string   `json:"id"`
+	Name        string   `json:"name"`
+	Description string   `json:"description,omitempty"`
+	Tags        []string `json:"tags,omitempty"`
+	Examples    []string `json:"examples,omitempty"`
+}
+
+// CardOptions 覆盖 BuildCard 的身份字段（空则用缺省）。
+type CardOptions struct {
+	Name        string
+	Description string
+	// URL JSON-RPC 端点（必填：远端没有端点就无法调用本团队）。
+	URL string
+	// Version 卡片版本（空 = "1.0.0"）。
+	Version string
+	// Skills 显式能力清单；空 = 从注册表派生。
+	Skills []AgentSkill
+}
+
+// BuildCard 从角色注册表与蓝图注册表渲染 Agent Card（描述本团队能力）。
+// 角色 → 技能（关键词作 tags）；蓝图 → 技能（match 词作 examples）。
+func BuildCard(reg *squad.RoleRegistry, bps *squad.BlueprintRegistry, opts CardOptions) (AgentCard, error) {
+	if strings.TrimSpace(opts.URL) == "" {
+		return AgentCard{}, fmt.Errorf("a2a: Agent Card 需要 JSON-RPC 端点 URL")
+	}
+	card := AgentCard{
+		ProtocolVersion: ProtocolVersion,
+		Name:            orDefault(opts.Name, "agent-squad"),
+		Description:     opts.Description,
+		URL:             opts.URL,
+		Version:         orDefault(opts.Version, "1.0.0"),
+		DefaultInputModes:  []string{"text/plain"},
+		DefaultOutputModes: []string{"text/plain"},
+		Skills:          append([]AgentSkill(nil), opts.Skills...),
+	}
+	if len(card.Skills) == 0 {
+		if reg != nil {
+			for _, role := range reg.List() {
+				desc := firstLine(role.Instructions)
+				if desc == "" {
+					desc = role.Name
+				}
+				card.Skills = append(card.Skills, AgentSkill{
+					ID: role.Role, Name: orDefault(role.Name, role.Role),
+					Description: desc, Tags: append([]string(nil), role.Keywords...),
+				})
+			}
+		}
+		if bps != nil {
+			for _, bp := range bps.List() {
+				card.Skills = append(card.Skills, AgentSkill{
+					ID: bp.Key, Name: orDefault(bp.Title, bp.Key),
+					Description: bp.Description, Examples: append([]string(nil), bp.Match...),
+				})
+			}
+		}
+	}
+	return card, nil
+}
+
+// CardHandler 以 JSON 服务 Agent Card（调用方挂载到 WellKnownPath）。
+func CardHandler(card AgentCard) http.Handler {
+	body, _ := json.Marshal(card)
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write(body)
+	})
+}
+
+// FetchCard 发现并校验远端 Agent Card（fail-closed：必备字段缺失即拒）。
+func FetchCard(client *http.Client, wellKnownURL string) (AgentCard, error) {
+	if client == nil {
+		client = http.DefaultClient
+	}
+	resp, err := client.Get(wellKnownURL)
+	if err != nil {
+		return AgentCard{}, fmt.Errorf("a2a: 获取 Agent Card: %w", err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		return AgentCard{}, fmt.Errorf("a2a: Agent Card 端点返回 %d", resp.StatusCode)
+	}
+	var card AgentCard
+	if err := json.NewDecoder(resp.Body).Decode(&card); err != nil {
+		return AgentCard{}, fmt.Errorf("a2a: Agent Card 解析失败: %w", err)
+	}
+	if err := validateCard(card); err != nil {
+		return AgentCard{}, err
+	}
+	return card, nil
+}
+
+// validateCard 消费侧最小校验（A2A 1.0 必备字段）。
+func validateCard(card AgentCard) error {
+	if card.ProtocolVersion == "" {
+		return fmt.Errorf("a2a: Agent Card 缺 protocolVersion")
+	}
+	if strings.TrimSpace(card.Name) == "" {
+		return fmt.Errorf("a2a: Agent Card 缺 name")
+	}
+	if strings.TrimSpace(card.URL) == "" {
+		return fmt.Errorf("a2a: Agent Card 缺 url")
+	}
+	if strings.TrimSpace(card.Version) == "" {
+		return fmt.Errorf("a2a: Agent Card 缺 version")
+	}
+	return nil
+}
+
+func orDefault(v, def string) string {
+	if strings.TrimSpace(v) != "" {
+		return v
+	}
+	return def
+}
+
+func firstLine(s string) string {
+	s = strings.TrimSpace(s)
+	if i := strings.IndexByte(s, '\n'); i >= 0 {
+		s = s[:i]
+	}
+	if len(s) > 120 {
+		s = s[:120] + "…"
+	}
+	return s
+}

adapters/a2a/conformance_test.go

@@ -0,0 +1,345 @@
+package a2a
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"agent-squad/squad"
+)
+
+// conformance_test.go — Q3 WP4 验收：双向 conformance（本地假 A2A 服务端）。
+// 发布侧：BuildCard + CardHandler 在 well-known 路径服务合法 Agent Card；
+// 消费侧：FetchCard 发现校验 + Executor 走完任务状态机
+// （submitted→working→completed / failed / input-required），终态对齐
+// squad.ExecResult。
+
+// fakeA2AServer 最小 A2A 1.0 服务端：well-known 卡片 + JSON-RPC
+// （message/send 建任务；tasks/get 按脚本推进状态）。
+type fakeA2AServer struct {
+	mu     sync.Mutex
+	card   AgentCard
+	tasks  map[string]*Task
+	plan   []string // 每次 tasks/get 推进到的状态序列（走完停在末态）
+	calls  map[string]int
+	artifacts []Artifact
+	statusMsg string
+}
+
+func newFakeServer(t *testing.T, card AgentCard, plan []string, artifacts []Artifact) *fakeA2AServer {
+	t.Helper()
+	s := &fakeA2AServer{card: card, tasks: map[string]*Task{}, plan: plan,
+		calls: map[string]int{}, artifacts: artifacts}
+	return s
+}
+
+func (s *fakeA2AServer) handler() http.Handler {
+	mux := http.NewServeMux()
+	mux.HandleFunc(WellKnownPath, func(w http.ResponseWriter, r *http.Request) {
+		s.mu.Lock()
+		body, _ := json.Marshal(s.card)
+		s.mu.Unlock()
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write(body)
+	})
+	mux.HandleFunc("/rpc", func(w http.ResponseWriter, r *http.Request) {
+		var req rpcRequest
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			writeRPCError(w, 0, -32700, "parse error")
+			return
+		}
+		s.mu.Lock()
+		defer s.mu.Unlock()
+		s.calls[req.Method]++
+		switch req.Method {
+		case "message/send":
+			id := fmt.Sprintf("task_%d", len(s.tasks)+1)
+			state := StateSubmitted
+			if len(s.plan) > 0 {
+				state = s.plan[0]
+			}
+			task := &Task{Kind: "task", ID: id, ContextID: "ctx_1",
+				Status: TaskStatus{State: state, Message: s.statusMessage()}}
+			s.tasks[id] = task
+			writeRPCResult(w, req.ID, task)
+		case "tasks/get":
+			var params struct {
+				ID string `json:"id"`
+			}
+			raw, _ := json.Marshal(req.Params)
+			_ = json.Unmarshal(raw, &params)
+			task, ok := s.tasks[params.ID]
+			if !ok {
+				writeRPCError(w, req.ID, -32001, "task not found")
+				return
+			}
+			// 按脚本推进状态机（停留在终态）。
+			if !isTerminal(task.Status.State) && len(s.plan) > 0 {
+				n := s.calls["tasks/get#"+params.ID]
+				s.calls["tasks/get#"+params.ID] = n + 1
+				idx := n + 1
+				if idx >= len(s.plan) {
+					idx = len(s.plan) - 1
+				}
+				task.Status.State = s.plan[idx]
+				task.Status.Message = s.statusMessage()
+				if task.Status.State == StateCompleted {
+					task.Artifacts = s.artifacts
+				}
+			}
+			writeRPCResult(w, req.ID, task)
+		default:
+			writeRPCError(w, req.ID, -32601, "method not found")
+		}
+	})
+	return mux
+}
+
+func (s *fakeA2AServer) statusMessage() *Message {
+	if s.statusMsg == "" {
+		return nil
+	}
+	return &Message{Kind: "message", Role: "agent",
+		Parts: []Part{{Kind: "text", Text: s.statusMsg}}}
+}
+
+func writeRPCResult(w http.ResponseWriter, id int64, result any) {
+	body, _ := json.Marshal(result)
+	env, _ := json.Marshal(rpcResponse{JSONRPC: "2.0", ID: id, Result: body})
+	w.Header().Set("Content-Type", "application/json")
+	_, _ = w.Write(env)
+}
+
+func writeRPCError(w http.ResponseWriter, id int64, code int, msg string) {
+	env, _ := json.Marshal(rpcResponse{JSONRPC: "2.0", ID: id, Error: &rpcError{Code: code, Message: msg}})
+	w.Header().Set("Content-Type", "application/json")
+	_, _ = w.Write(env)
+}
+
+// ---- 发布侧 ----
+
+func TestBuildCardFromRegistries(t *testing.T) {
+	reg := squad.NewRoleRegistry()
+	for _, r := range []squad.RoleSpec{
+		{Role: "researcher", Name: "调研员", Keywords: []string{"调研", "检索"},
+			Instructions: "围绕目标调研关键问题。\n第二行不进摘要。"},
+		{Role: "writer", Name: "撰稿员", Keywords: []string{"撰写"}},
+	} {
+		if err := reg.Register(r); err != nil {
+			t.Fatal(err)
+		}
+	}
+	bps := squad.NewBlueprintRegistry()
+	if err := bps.Register(squad.Blueprint{Key: "brief", Title: "简报",
+		Description: "生成简报", Match: []string{"简报", "brief"},
+		Steps: []squad.StepSpec{{ID: "s1", Role: "writer", Title: "成文"}}}); err != nil {
+		t.Fatal(err)
+	}
+	card, err := BuildCard(reg, bps, CardOptions{
+		Name: "示例小队", Description: "演示团队能力", URL: "https://team.example/rpc",
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if card.ProtocolVersion != ProtocolVersion || card.Version != "1.0.0" {
+		t.Fatalf("card = %+v", card)
+	}
+	byID := map[string]AgentSkill{}
+	for _, s := range card.Skills {
+		byID[s.ID] = s
+	}
+	if byID["researcher"].Name != "调研员" || byID["researcher"].Description != "围绕目标调研关键问题。" {
+		t.Fatalf("role skill = %+v", byID["researcher"])
+	}
+	if len(byID["researcher"].Tags) != 2 {
+		t.Fatalf("tags = %v", byID["researcher"].Tags)
+	}
+	if byID["brief"].Name != "简报" || strings.Join(byID["brief"].Examples, ",") != "简报,brief" {
+		t.Fatalf("blueprint skill = %+v", byID["brief"])
+	}
+	if _, err := BuildCard(reg, bps, CardOptions{}); err == nil {
+		t.Fatal("缺 URL 必须 fail-closed")
+	}
+}
+
+// CardHandler 以 JSON 服务卡片（发布端点形态）。
+func TestCardHandlerServesJSON(t *testing.T) {
+	card := AgentCard{ProtocolVersion: ProtocolVersion, Name: "小队", URL: "https://x/rpc", Version: "1.0.0"}
+	ts := httptest.NewServer(CardHandler(card))
+	defer ts.Close()
+	resp, err := http.Get(ts.URL + WellKnownPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if ct := resp.Header.Get("Content-Type"); ct != "application/json" {
+		t.Fatalf("content-type = %s", ct)
+	}
+	var got AgentCard
+	if err := json.NewDecoder(resp.Body).Decode(&got); err != nil {
+		t.Fatal(err)
+	}
+	if got.Name != "小队" || got.ProtocolVersion != ProtocolVersion {
+		t.Fatalf("card = %+v", got)
+	}
+}
+
+// ---- 消费侧：发现 + 状态机 ----
+
+func TestFetchCardAndExecuteCompleted(t *testing.T) {
+	fileBytes := base64.StdEncoding.EncodeToString([]byte("notes 内容"))
+	artifacts := []Artifact{{
+		ArtifactID: "art1", Name: "调研结果",
+		Parts: []Part{
+			{Kind: "text", Text: "# 调研结论\n\n结论正文，长度足够作为交付物内容。"},
+			{Kind: "file", File: &FilePart{Name: "notes.md", Bytes: fileBytes, MimeType: "text/markdown"}},
+		},
+	}}
+	card := AgentCard{ProtocolVersion: ProtocolVersion, Name: "远端小队",
+		URL: "PLACEHOLDER", Version: "1.0.0"}
+	srv := newFakeServer(t, card, []string{StateWorking, StateWorking, StateCompleted}, artifacts)
+	ts := httptest.NewServer(srv.handler())
+	defer ts.Close()
+	srv.mu.Lock()
+	srv.card.URL = ts.URL + "/rpc"
+	srv.mu.Unlock()
+
+	// 发现：well-known 路径取卡并校验。
+	got, err := FetchCard(ts.Client(), ts.URL+WellKnownPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got.Name != "远端小队" || got.URL != ts.URL+"/rpc" {
+		t.Fatalf("card = %+v", got)
+	}
+
+	// 执行：submitted/working → completed，工件映射 patches。
+	var states []string
+	ex := NewExecutor(got)
+	ex.Client = ts.Client()
+	ex.PollInterval = 5 * time.Millisecond
+	ex.OnState = func(s string) { states = append(states, s) }
+	res, err := ex.Execute(context.Background(), squad.ExecRequest{
+		Prompt: "调研主题 X", Targets: []string{"output.md"},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !res.Success {
+		t.Fatalf("result = %+v", res)
+	}
+	if string(res.Patches["notes.md"]) != "notes 内容" {
+		t.Fatalf("file part 未落成 patch：%q", res.Patches["notes.md"])
+	}
+	if !strings.Contains(string(res.Patches["output.md"]), "调研结论") {
+		t.Fatalf("文本部件未写入目标：%q", res.Patches["output.md"])
+	}
+	joined := strings.Join(states, ",")
+	if !strings.Contains(joined, StateWorking) || !strings.HasSuffix(joined, StateCompleted) {
+		t.Fatalf("状态机迁移 = %v", states)
+	}
+	srv.mu.Lock()
+	sends := srv.calls["message/send"]
+	srv.mu.Unlock()
+	if sends != 1 {
+		t.Fatalf("message/send = %d", sends)
+	}
+}
+
+func TestExecuteMapsFailedAndInputRequired(t *testing.T) {
+	card := AgentCard{ProtocolVersion: ProtocolVersion, Name: "远端", URL: "PLACEHOLDER", Version: "1"}
+	srv := newFakeServer(t, card, []string{StateWorking, StateFailed}, nil)
+	srv.statusMsg = "远端执行崩溃"
+	ts := httptest.NewServer(srv.handler())
+	defer ts.Close()
+	srv.mu.Lock()
+	srv.card.URL = ts.URL + "/rpc"
+	srv.mu.Unlock()
+
+	ex := NewExecutor(card)
+	ex.BaseURL = ts.URL + "/rpc"
+	ex.Client = ts.Client()
+	ex.PollInterval = 5 * time.Millisecond
+	res, err := ex.Execute(context.Background(), squad.ExecRequest{Prompt: "x", Targets: []string{"output.md"}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Success || !strings.Contains(res.ErrorReason, "failed") || !strings.Contains(res.ErrorReason, "远端执行崩溃") {
+		t.Fatalf("failed 映射 = %+v", res)
+	}
+
+	// input-required：fail-closed（跨进程人工输入不在适配面内）。
+	srv2 := newFakeServer(t, card, []string{StateInputRequired}, nil)
+	srv2.statusMsg = "请补充授权"
+	ts2 := httptest.NewServer(srv2.handler())
+	defer ts2.Close()
+	ex2 := &Executor{BaseURL: ts2.URL + "/rpc", Client: ts2.Client(), PollInterval: 5 * time.Millisecond}
+	res2, err := ex2.Execute(context.Background(), squad.ExecRequest{Prompt: "x", Targets: []string{"output.md"}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res2.Success || !strings.Contains(res2.ErrorReason, "input-required") {
+		t.Fatalf("input-required 映射 = %+v", res2)
+	}
+}
+
+// 直接回 Message（无任务态）→ 文本落目标。
+func TestExecuteDirectMessageResult(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var req rpcRequest
+		_ = json.NewDecoder(r.Body).Decode(&req)
+		writeRPCResult(w, req.ID, Message{Kind: "message", Role: "agent",
+			Parts: []Part{{Kind: "text", Text: "直接回答正文"}}})
+	}))
+	defer ts.Close()
+	ex := &Executor{BaseURL: ts.URL, Client: ts.Client()}
+	res, err := ex.Execute(context.Background(), squad.ExecRequest{Prompt: "x", Targets: []string{"output.md"}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !res.Success || !strings.Contains(string(res.Patches["output.md"]), "直接回答正文") {
+		t.Fatalf("res = %+v", res)
+	}
+}
+
+// 传输/协议错误 → error（引擎按瞬态评估），不吞成成功。
+func TestExecuteProtocolErrors(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		writeRPCError(w, 1, -32601, "method not found")
+	}))
+	defer ts.Close()
+	ex := &Executor{BaseURL: ts.URL, Client: ts.Client()}
+	if _, err := ex.Execute(context.Background(), squad.ExecRequest{Prompt: "x"}); err == nil ||
+		!strings.Contains(err.Error(), "协议错误") {
+		t.Fatalf("err = %v", err)
+	}
+	// ctx 取消传播。
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	slow := newFakeServer(t, AgentCard{ProtocolVersion: "1.0", Name: "x", URL: ts.URL, Version: "1"},
+		[]string{StateWorking}, nil)
+	ts2 := httptest.NewServer(slow.handler())
+	defer ts2.Close()
+	ex2 := &Executor{BaseURL: ts2.URL + "/rpc", Client: ts2.Client(), PollInterval: time.Second}
+	if _, err := ex2.Execute(ctx, squad.ExecRequest{Prompt: "x"}); err == nil {
+		t.Fatal("取消必须传播")
+	}
+}
+
+// FetchCard fail-closed：缺必备字段拒绝。
+func TestFetchCardValidates(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, _ = w.Write([]byte(`{"protocolVersion":"1.0","name":"","url":"","version":""}`))
+	}))
+	defer ts.Close()
+	if _, err := FetchCard(ts.Client(), ts.URL); err == nil || !strings.Contains(err.Error(), "name") {
+		t.Fatalf("err = %v", err)
+	}
+}

adapters/a2a/executor.go

@@ -0,0 +1,331 @@
+package a2a
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"agent-squad/squad"
+)
+
+// executor.go — 远端智能体 Executor 客户端（A2A 任务状态机对齐 ExecResult）。
+
+// 任务状态（A2A 1.0 TaskState）。
+const (
+	StateSubmitted    = "submitted"
+	StateWorking      = "working"
+	StateInputRequired = "input-required"
+	StateCompleted    = "completed"
+	StateCanceled     = "canceled"
+	StateFailed       = "failed"
+	StateRejected     = "rejected"
+)
+
+// DefaultPollInterval 是 tasks/get 轮询缺省间隔。
+const DefaultPollInterval = 500 * time.Millisecond
+
+// Executor 把远端 A2A 智能体接成 squad.Executor：一次步骤执行 = 一个
+// A2A 任务（message/send 发起，tasks/get 轮询到终态）。
+type Executor struct {
+	// BaseURL 远端 JSON-RPC 端点（Agent Card 的 url）。
+	BaseURL string
+	// Client HTTP 客户端（nil = http.DefaultClient）。
+	Client *http.Client
+	// PollInterval 轮询间隔（0 = DefaultPollInterval）。
+	PollInterval time.Duration
+	// OnState 可选状态回调（观测任务状态机迁移）。
+	OnState func(state string)
+
+	callID atomic.Int64
+}
+
+// NewExecutor 按 Agent Card 构造远端执行器。
+func NewExecutor(card AgentCard) *Executor {
+	return &Executor{BaseURL: card.URL}
+}
+
+// Name 实现 squad.Executor。
+func (e *Executor) Name() string { return "a2a" }
+
+// ---- A2A 1.0 报文形态（JSON-RPC 2.0） ----
+
+type rpcRequest struct {
+	JSONRPC string `json:"jsonrpc"`
+	ID      int64  `json:"id"`
+	Method  string `json:"method"`
+	Params  any    `json:"params"`
+}
+
+type rpcError struct {
+	Code    int    `json:"code"`
+	Message string `json:"message"`
+}
+
+type rpcResponse struct {
+	JSONRPC string          `json:"jsonrpc"`
+	ID      int64           `json:"id"`
+	Result  json.RawMessage `json:"result,omitempty"`
+	Error   *rpcError       `json:"error,omitempty"`
+}
+
+// Part 是消息/工件的部件（text | file | data）。
+type Part struct {
+	Kind string     `json:"kind"`
+	Text string     `json:"text,omitempty"`
+	File *FilePart  `json:"file,omitempty"`
+	Data *json.RawMessage `json:"data,omitempty"`
+}
+
+// FilePart 文件部件：bytes（base64）或 uri 二选一。
+type FilePart struct {
+	Name     string `json:"name"`
+	Bytes    string `json:"bytes,omitempty"`
+	URI      string `json:"uri,omitempty"`
+	MimeType string `json:"mimeType,omitempty"`
+}
+
+// Message 是一条 A2A 消息。
+type Message struct {
+	Kind      string `json:"kind"`
+	Role      string `json:"role"`
+	Parts     []Part `json:"parts"`
+	MessageID string `json:"messageId"`
+}
+
+// TaskStatus 任务状态。
+type TaskStatus struct {
+	State    string   `json:"state"`
+	Message  *Message `json:"message,omitempty"`
+	Timestamp string  `json:"timestamp,omitempty"`
+}
+
+// Artifact 任务工件。
+type Artifact struct {
+	ArtifactID string `json:"artifactId,omitempty"`
+	Name       string `json:"name,omitempty"`
+	Parts      []Part `json:"parts"`
+}
+
+// Task 是 A2A 任务（状态机载体）。
+type Task struct {
+	Kind      string     `json:"kind"`
+	ID        string     `json:"id"`
+	ContextID string     `json:"contextId,omitempty"`
+	Status    TaskStatus `json:"status"`
+	Artifacts []Artifact `json:"artifacts,omitempty"`
+}
+
+// Execute 实现 squad.Executor：发起任务并轮询到终态，映射 ExecResult。
+// 传输/协议错误返回 error（引擎按瞬态失败评估）；任务级失败
+// （failed/canceled/rejected/input-required）返回 Success=false 的结果
+// （fail-closed：跨进程人工输入不在本适配面内）。
+func (e *Executor) Execute(ctx context.Context, req squad.ExecRequest) (*squad.ExecResult, error) {
+	if strings.TrimSpace(e.BaseURL) == "" {
+		return nil, fmt.Errorf("a2a: executor 缺 BaseURL")
+	}
+	prompt := strings.TrimSpace(req.Prompt)
+	if prompt == "" {
+		prompt = strings.TrimSpace(req.Instructions)
+	}
+	msg := Message{
+		Kind: "message", Role: "user",
+		Parts:     []Part{{Kind: "text", Text: prompt}},
+		MessageID: fmt.Sprintf("msg-%d-%d", time.Now().UnixNano(), e.callID.Add(1)),
+	}
+	raw, err := e.call(ctx, "message/send", map[string]any{"message": msg})
+	if err != nil {
+		return nil, err
+	}
+	// 服务端可直接回 Message（无任务态）或 Task。
+	var probe struct {
+		Kind string `json:"kind"`
+	}
+	_ = json.Unmarshal(raw, &probe)
+	if probe.Kind == "message" {
+		var m Message
+		if err := json.Unmarshal(raw, &m); err != nil {
+			return nil, fmt.Errorf("a2a: message 结果解析失败: %w", err)
+		}
+		return e.resultFromParts(m.Parts, req.Targets), nil
+	}
+	var task Task
+	if err := json.Unmarshal(raw, &task); err != nil {
+		return nil, fmt.Errorf("a2a: task 结果解析失败: %w", err)
+	}
+	e.observe(task.Status.State)
+	if shouldStop(task.Status.State) {
+		return e.resultFromTask(task, req.Targets), nil
+	}
+	// 轮询任务状态机直至终态（ctx 取消传播）。
+	interval := e.PollInterval
+	if interval <= 0 {
+		interval = DefaultPollInterval
+	}
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		case <-ticker.C:
+		}
+		raw, err := e.call(ctx, "tasks/get", map[string]any{"id": task.ID})
+		if err != nil {
+			return nil, err
+		}
+		var next Task
+		if err := json.Unmarshal(raw, &next); err != nil {
+			return nil, fmt.Errorf("a2a: tasks/get 解析失败: %w", err)
+		}
+		if next.Status.State != task.Status.State {
+			task = next
+			e.observe(task.Status.State)
+		} else {
+			task = next
+		}
+		if shouldStop(task.Status.State) {
+			return e.resultFromTask(task, req.Targets), nil
+		}
+	}
+}
+
+// call 发一次 JSON-RPC 调用并取 result。
+func (e *Executor) call(ctx context.Context, method string, params any) (json.RawMessage, error) {
+	client := e.Client
+	if client == nil {
+		client = http.DefaultClient
+	}
+	body, _ := json.Marshal(rpcRequest{
+		JSONRPC: "2.0", ID: e.callID.Add(1), Method: method, Params: params,
+	})
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, e.BaseURL, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("a2a: %s 传输失败: %w", method, err)
+	}
+	defer resp.Body.Close()
+	data, err := io.ReadAll(io.LimitReader(resp.Body, 8<<20))
+	if err != nil {
+		return nil, fmt.Errorf("a2a: %s 读取响应失败: %w", method, err)
+	}
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("a2a: %s 返回 HTTP %d", method, resp.StatusCode)
+	}
+	var env rpcResponse
+	if err := json.Unmarshal(data, &env); err != nil {
+		return nil, fmt.Errorf("a2a: %s 响应不是合法 JSON-RPC: %w", method, err)
+	}
+	if env.Error != nil {
+		return nil, fmt.Errorf("a2a: %s 协议错误 %d: %s", method, env.Error.Code, env.Error.Message)
+	}
+	return env.Result, nil
+}
+
+func (e *Executor) observe(state string) {
+	if e.OnState != nil {
+		e.OnState(state)
+	}
+}
+
+func isTerminal(state string) bool {
+	switch state {
+	case StateCompleted, StateFailed, StateCanceled, StateRejected:
+		return true
+	}
+	return false
+}
+
+// shouldStop 轮询停止条件：真终态，或 input-required（跨进程人工输入不在
+// 本适配面内，fail-closed 交引擎语义处理，不死等）。
+func shouldStop(state string) bool {
+	return isTerminal(state) || state == StateInputRequired
+}
+
+// resultFromTask 终态任务 → ExecResult。
+func (e *Executor) resultFromTask(task Task, targets []string) *squad.ExecResult {
+	switch task.Status.State {
+	case StateCompleted:
+		var parts []Part
+		for _, art := range task.Artifacts {
+			parts = append(parts, art.Parts...)
+		}
+		return e.resultFromParts(parts, targets)
+	case StateInputRequired:
+		return &squad.ExecResult{Success: false,
+			ErrorReason: "a2a: 远端要求人工输入（input-required）：" + statusText(task.Status)}
+	case StateCanceled:
+		return &squad.ExecResult{Success: false,
+			ErrorReason: "a2a: 远端任务被取消（canceled）：" + statusText(task.Status)}
+	case StateRejected:
+		return &squad.ExecResult{Success: false,
+			ErrorReason: "a2a: 远端拒绝任务（rejected）：" + statusText(task.Status)}
+	default: // failed 及未知终态一律 fail-closed
+		return &squad.ExecResult{Success: false,
+			ErrorReason: "a2a: 远端任务失败（" + task.Status.State + "）：" + statusText(task.Status)}
+	}
+}
+
+// resultFromParts 部件流 → patches：FilePart(bytes) 按名落 patch；
+// 文本部件拼接后写入全部声明目标（无文件工件时的交付物兜底，
+// 与其他后端「正文写目标文件」契约一致）。
+func (e *Executor) resultFromParts(parts []Part, targets []string) *squad.ExecResult {
+	patches := map[string][]byte{}
+	var text strings.Builder
+	for _, p := range parts {
+		switch p.Kind {
+		case "text":
+			if text.Len() > 0 {
+				text.WriteString("\n")
+			}
+			text.WriteString(p.Text)
+		case "file":
+			if p.File == nil || p.File.Name == "" {
+				continue
+			}
+			data, err := base64.StdEncoding.DecodeString(p.File.Bytes)
+			if err != nil {
+				continue // uri 形态与坏 base64 不落 patch（消费侧最小面）
+			}
+			patches[p.File.Name] = data
+		}
+	}
+	body := strings.TrimSpace(text.String())
+	if len(targets) == 0 {
+		targets = []string{"output.md"}
+	}
+	if body != "" {
+		for _, t := range targets {
+			if _, ok := patches[t]; !ok {
+				patches[t] = []byte(body + "\n")
+			}
+		}
+	}
+	if len(patches) == 0 {
+		return &squad.ExecResult{Success: false, ErrorReason: "a2a: 完成任务无任何工件"}
+	}
+	return &squad.ExecResult{Success: true, Patches: patches, Logs: body}
+}
+
+func statusText(st TaskStatus) string {
+	if st.Message == nil {
+		return ""
+	}
+	var b strings.Builder
+	for _, p := range st.Message.Parts {
+		if p.Kind == "text" {
+			b.WriteString(p.Text)
+		}
+	}
+	return b.String()
+}

adapters/a2a/go.mod

@@ -0,0 +1,11 @@
+module agent-squad/adapters/a2a
+
+go 1.27
+
+require agent-squad v0.0.0
+
+require error-code-system v0.0.0 // indirect
+
+replace agent-squad => ../..
+
+replace error-code-system => ../../deps/error-code-system

squad/brief_test.go

@@ -0,0 +1,41 @@
+package squad
+
+import (
+	"context"
+	"strings"
+	"testing"
+)
+
+// brief_test.go — Q3 WP1a：StepSpec.Brief 渲染进 TASK.md「任务指令」节。
+
+func TestStepBriefRendersIntoTaskFile(t *testing.T) {
+	rec := &promptRecordingBackend{prompts: map[string][]string{}}
+	engine := newRecordingEngine(t, rec, []StepSpec{
+		{ID: "s1", Role: "researcher", Title: "起草", Targets: []string{"output.md"},
+			Brief: "写一份关于「太空电梯」的简报，篇幅：短。\n必须包含单独一行「核对标记：P4」。"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "带任务指令"}, RunOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("status = %s err = %v", res.Status, res.Error)
+	}
+	var prompt string
+	for _, p := range rec.prompts["01_researcher"] {
+		prompt += p
+	}
+	if !strings.Contains(prompt, "## 任务指令") {
+		t.Fatalf("TASK.md 缺任务指令节：%q", prompt)
+	}
+	if !strings.Contains(prompt, "核对标记：P4") {
+		t.Fatalf("任务指令正文缺失：%q", prompt)
+	}
+	// 指令节在期望产出之后、上下文表之前。
+	iOut := strings.Index(prompt, "期望产出")
+	iBrief := strings.Index(prompt, "## 任务指令")
+	iCtx := strings.Index(prompt, "## 任务上下文资源")
+	if !(iOut < iBrief && iBrief < iCtx) {
+		t.Fatalf("任务指令节位置错误：%d/%d/%d", iOut, iBrief, iCtx)
+	}
+}

squad/engine.go

@@ -114,6 +114,19 @@ type RunOptions struct {
 	// MaxReplans leader 模式的重规划上限（Q2；与 MaxLeaderTurns 独立）。
 	// 0 = 默认 DefaultMaxReplans。
 	MaxReplans int `json:"max_replans,omitempty"`
+	// GroupChatPolicy group_chat 拓扑发言人策略（Q2）：rotate（默认）| moderator。
+	GroupChatPolicy string `json:"group_chat_policy,omitempty"`
+	// GroupChatModerator 主持人角色 key（moderator 策略必填，须在名册内）。
+	GroupChatModerator string `json:"group_chat_moderator,omitempty"`
+	// GroupChatMaxTurns 群聊轮次预算（0 = DefaultMaxGroupChatTurns）。
+	GroupChatMaxTurns int `json:"group_chat_max_turns,omitempty"`
+	// ReviewVerifyRole review 拓扑核实角色 key（默认 "verifier"）。
+	ReviewVerifyRole string `json:"review_verify_role,omitempty"`
+	// ReviewTarget 被评审材料（默认取 context/goal.md）。
+	ReviewTarget string `json:"review_target,omitempty"`
+	// TaskBoardLeaseSeconds task_board 任务租约时限（秒；0 = 默认 600）。
+	// 孤儿租约（claimed 且过期）在驱动重入时再武装回 open。
+	TaskBoardLeaseSeconds int `json:"task_board_lease_seconds,omitempty"`
 }
 
 // SquadEngine 小队引擎门面：Run / Respond / Resume / Inspect / ListRuns。
@@ -250,6 +263,11 @@ func (e *SquadEngine) Run(ctx context.Context, goal Goal, runOpts RunOptions) (*
 	}
 	if runOpts.Topology != "" {
 		meta.Metadata["topology"] = runOpts.Topology
+		// leader 拓扑映射到委派循环须发生在计划确认之前（确认门按
+		// mode=leader 豁免）；后置映射会让 leader 运行误触计划确认。
+		if runOpts.Topology == TopologyLeader && meta.Metadata["mode"] == "" {
+			meta.Metadata["mode"] = "leader"
+		}
 	}
 	if !runOpts.Deadline.IsZero() {
 		// RFC3339Nano：秒级 RFC3339 会截断亚秒精度，短截止会被立刻判超期。
@@ -258,6 +276,24 @@ func (e *SquadEngine) Run(ctx context.Context, goal Goal, runOpts RunOptions) (*
 	if runOpts.MaxReplans > 0 {
 		meta.Metadata["max_replans"] = fmt.Sprintf("%d", runOpts.MaxReplans)
 	}
+	if runOpts.GroupChatPolicy != "" {
+		meta.Metadata["group_chat_policy"] = runOpts.GroupChatPolicy
+	}
+	if runOpts.GroupChatModerator != "" {
+		meta.Metadata["group_chat_moderator"] = runOpts.GroupChatModerator
+	}
+	if runOpts.GroupChatMaxTurns > 0 {
+		meta.Metadata["group_chat_max_turns"] = fmt.Sprintf("%d", runOpts.GroupChatMaxTurns)
+	}
+	if runOpts.ReviewVerifyRole != "" {
+		meta.Metadata["review_verify_role"] = runOpts.ReviewVerifyRole
+	}
+	if runOpts.ReviewTarget != "" {
+		meta.Metadata["review_target"] = runOpts.ReviewTarget
+	}
+	if runOpts.TaskBoardLeaseSeconds > 0 {
+		meta.Metadata["task_board_lease_seconds"] = fmt.Sprintf("%d", runOpts.TaskBoardLeaseSeconds)
+	}
 	e.deps.Sink.Emit(Event{Type: EvRunStarted, RunID: runID, Text: goal.Text, At: time.Now()})
 
 	// 意图闸门（可选，入口一次裁决；显式 TaskKey 优先，不重复过闸）。
@@ -434,6 +470,15 @@ func (e *SquadEngine) planAndExecute(ctx context.Context, st *RunState, runOpts
 		}
 		return out, nil
 	}
+	// driver 类拓扑（Q2 WP3+）：按名分发专用驱动（review/group_chat；
+	// task_board 属 WP4，未点亮前 checkTopology 已 fail-closed）。
+	if out, handled, derr := e.dispatchTopologyDriver(ctx, st); handled {
+		if derr != nil {
+			return nil, derr
+		}
+		e.finalizeEvent(out)
+		return out, nil
+	}
 	out, _, err := drv.advance(ctx, st)
 	if err != nil {
 		return nil, err
@@ -494,6 +539,15 @@ func (e *SquadEngine) resumeAfterHold(ctx context.Context, st *RunState) (*RunRe
 		}
 		return out, nil
 	}
+	// driver 类拓扑续跑：驱动自身幂等（review 已完成 finder 不重跑；
+	// group_chat 按已落盘轮次续转）。
+	if out, handled, err := e.dispatchTopologyDriver(ctx, st); handled {
+		if err != nil {
+			return nil, err
+		}
+		e.finalizeEvent(out)
+		return out, nil
+	}
 	drv := &flowDriver{opts: e.deps}
 	out, _, err := drv.advance(ctx, st)
 	if err != nil {
@@ -503,6 +557,32 @@ func (e *SquadEngine) resumeAfterHold(ctx context.Context, st *RunState) (*RunRe
 	return out, nil
 }
 
+// dispatchTopologyDriver 按运行拓扑分发 driver 类拓扑。
+// handled=false 表示非 driver 拓扑（走既有图/模式路径）。
+func (e *SquadEngine) dispatchTopologyDriver(ctx context.Context, st *RunState) (*RunResult, bool, error) {
+	topo := st.Meta.Metadata["topology"]
+	if topo == "" {
+		return nil, false, nil
+	}
+	spec, ok := LookupTopology(topo)
+	if !ok || spec.Kind != TopologyDriver {
+		return nil, false, nil
+	}
+	switch topo {
+	case TopologyReview:
+		out, err := e.runReviewDriver(ctx, st)
+		return out, true, err
+	case TopologyGroupChat:
+		out, err := e.runGroupChatDriver(ctx, st)
+		return out, true, err
+	case TopologyTaskBoard:
+		out, err := e.runTaskBoardDriver(ctx, st)
+		return out, true, err
+	default:
+		return e.driverFail(st, fmt.Sprintf("topology: %q 驱动未实现（fail-closed）", topo)), true, nil
+	}
+}
+
 // materializeWorkspace 落盘工作区与子工作区（已存在则只更新计划并重建待执行子目录）。
 func (e *SquadEngine) materializeWorkspace(meta *RunMetadata, st *RunState, plan *SquadPlan) error {
 	if st.Meta.WorkDir == "" {

squad/groupchat.go

@@ -0,0 +1,355 @@
+package squad
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+// groupchat.go — group_chat 拓扑驱动（Q2 WP3）。
+// 形态（计划 §三 WP3 与边界 §五）：共享转录（BB 字段 transcript +
+// group_chat/transcript.md 全量落盘）；发言人策略只做**轮转**与**主持人**
+// 两种（脚本可判定，LLM 选人策略不进库）；预算停机（max_turns，缺省 8）。
+// 蓝图步骤 = 参与者名册（按序，不直接执行，driver 标记 skipped 并派生轮次
+// 步骤）；任一发言含 [close] 标记即收口；主持人模式下主持人输出 JSON 决策
+// （{"next":"role"} / {"action":"close"}），未知角色/非法 JSON fail-closed。
+// 驱动幂等可恢复：轮次由已落盘的 gc 步骤数重建，挂起（权限/HITL）后
+// Respond 重入续转。
+
+func init() {
+	_ = RegisterTopologyDriver(TopologyGroupChat)
+}
+
+// DefaultMaxGroupChatTurns 群聊轮次预算缺省值（预算停机）。
+const DefaultMaxGroupChatTurns = 8
+
+// gcRosterSkipReason 名册步骤的 skipped 原因（非执行步骤，不算降级）。
+const gcRosterSkipReason = "group_chat: 名册步骤（参与者由驱动接管）"
+
+// gcCloseMarker 任一发言包含该标记（大小写不敏感）即收口。
+const gcCloseMarker = "[close]"
+
+// gcTranscriptCapBB 是 BB 转录字段的容量上限（TASK.md 快照只带近端）。
+const gcTranscriptCapBB = 4000
+
+// runGroupChatDriver group_chat 拓扑入口。
+func (e *SquadEngine) runGroupChatDriver(ctx context.Context, st *RunState) (*RunResult, error) {
+	drv := &flowDriver{opts: e.deps}
+
+	// 名册：首次进入从蓝图步骤取参与者序列并持久化到元数据（恢复时直读）。
+	roster, err := e.gcRoster(st)
+	if err != nil {
+		return e.driverFail(st, err.Error()), nil
+	}
+	policy := orDefault(st.Meta.Metadata["group_chat_policy"], "rotate")
+	moderator := st.Meta.Metadata["group_chat_moderator"]
+	if policy != "rotate" && policy != "moderator" {
+		return e.driverFail(st, fmt.Sprintf("group_chat: 未知发言人策略 %q（只支持 rotate/moderator）", policy)), nil
+	}
+	if policy == "moderator" {
+		if moderator == "" || !containsString(roster, moderator) {
+			return e.driverFail(st, fmt.Sprintf("group_chat: 主持人 %q 不在名册内（fail-closed）", moderator)), nil
+		}
+	}
+	maxTurns := DefaultMaxGroupChatTurns
+	if v := st.Meta.Metadata["group_chat_max_turns"]; v != "" {
+		if n := parseIntDefault(v, DefaultMaxGroupChatTurns); n > 0 {
+			maxTurns = n
+		}
+	}
+
+	// 名册步骤标记 skipped（首次进入时；恢复重入无 pending 名册步骤）。
+	st.mu.Lock()
+	for i := range st.Plan.Workflow.Steps {
+		s := &st.Plan.Workflow.Steps[i]
+		if !strings.HasPrefix(s.ID, "gc") && (s.Status == "pending" || s.Status == "running") {
+			s.Status = "skipped"
+			s.Error = gcRosterSkipReason
+		}
+	}
+	_ = st.save()
+	st.mu.Unlock()
+
+	for {
+		// 恢复重入：上次挂起留下的未完 gc 轮次步骤优先续跑（不重新选人）。
+		if idx := e.gcHeldStepIdx(st); idx >= 0 {
+			out, gate, err := e.gcRunStep(ctx, drv, st, idx)
+			if err != nil {
+				return nil, err
+			}
+			if gate != nil {
+				if out == nil {
+					out = heldResult(st, gate)
+				}
+				return out, nil
+			}
+			if out != nil {
+				return out, nil
+			}
+			if e.gcMessageClosed(st, idx) {
+				drv.emit(st, Event{Type: EvPhase, Text: fmt.Sprintf("group_chat：%s 发出收口标记，停机", st.Plan.Workflow.Steps[idx].Role)})
+				break
+			}
+			continue
+		}
+		turns := e.gcTurnCount(st)
+		if turns >= maxTurns {
+			drv.emit(st, Event{Type: EvPhase, Text: fmt.Sprintf("group_chat：轮次预算 %d 用尽，停机收口", maxTurns)})
+			break
+		}
+		speaker, closed, derr := e.gcNextSpeaker(st, roster, policy, moderator, turns)
+		if derr != nil {
+			return e.driverFail(st, derr.Error()), nil
+		}
+		if closed {
+			drv.emit(st, Event{Type: EvPhase, Text: "group_chat：主持人收口"})
+			break
+		}
+		out, gate, err := e.gcRunTurn(ctx, drv, st, turns, speaker)
+		if err != nil {
+			return nil, err
+		}
+		if gate != nil {
+			if out == nil {
+				out = heldResult(st, gate)
+			}
+			return out, nil
+		}
+		if out != nil { // 轮次步骤失败（关键）→ fail-closed 传播
+			return out, nil
+		}
+		if e.gcMessageClosed(st, len(st.Plan.Workflow.Steps)-1) {
+			drv.emit(st, Event{Type: EvPhase, Text: fmt.Sprintf("group_chat：%s 发出收口标记，停机", speaker)})
+			break
+		}
+	}
+	return e.gcFinish(st, drv), nil
+}
+
+// gcRoster 参与者名册（首次从蓝图步骤派生并写入元数据；恢复直读）。
+func (e *SquadEngine) gcRoster(st *RunState) ([]string, error) {
+	if v := st.Meta.Metadata["group_chat_roster"]; v != "" {
+		return strings.Split(v, ","), nil
+	}
+	var roster []string
+	for _, s := range st.Plan.Workflow.Steps {
+		if s.Role != "" && !containsString(roster, s.Role) {
+			roster = append(roster, s.Role)
+		}
+	}
+	if len(roster) == 0 {
+		return nil, fmt.Errorf("group_chat: 名册为空（蓝图步骤即参与者）")
+	}
+	st.mu.Lock()
+	if st.Meta.Metadata == nil {
+		st.Meta.Metadata = map[string]string{}
+	}
+	st.Meta.Metadata["group_chat_roster"] = strings.Join(roster, ",")
+	_ = st.save()
+	st.mu.Unlock()
+	return roster, nil
+}
+
+// gcTurnCount 已完成的轮次数（预算与轮转序号的基准；恢复重入自然续算）。
+func (e *SquadEngine) gcTurnCount(st *RunState) int {
+	n := 0
+	for _, s := range st.Plan.Workflow.Steps {
+		if strings.HasPrefix(s.ID, "gc") && s.Status == "completed" {
+			n++
+		}
+	}
+	return n
+}
+
+// gcHeldStepIdx 返回上次挂起留下的未完 gc 轮次步骤下标（无则 -1）。
+func (e *SquadEngine) gcHeldStepIdx(st *RunState) int {
+	for i := range st.Plan.Workflow.Steps {
+		s := &st.Plan.Workflow.Steps[i]
+		if strings.HasPrefix(s.ID, "gc") && (s.Status == "pending" || s.Status == "running") {
+			return i
+		}
+	}
+	return -1
+}
+
+// gcNextSpeaker 决定下一发言人。rotate = 轮转；moderator = 主持人裁决
+// （上一步是参与者发言 → 主持人接手；主持人决策 close → 收口，next → 指名，
+// 非法 JSON / 未知角色 fail-closed）。
+func (e *SquadEngine) gcNextSpeaker(st *RunState, roster []string, policy, moderator string, turns int) (string, bool, error) {
+	if policy == "rotate" {
+		return roster[turns%len(roster)], false, nil
+	}
+	last := e.gcLastStep(st)
+	if last == nil || last.Role == moderator {
+		// 首轮或上一步就是主持人（不该连续，防御性让主持人接手）。
+		if last != nil && last.Role == moderator {
+			// 解析主持人决策。
+			dec, err := e.gcParseDecision(st, last)
+			if err != nil {
+				return "", false, err
+			}
+			if dec.Action == "close" {
+				return "", true, nil
+			}
+			if !containsString(roster, dec.Next) {
+				return "", false, fmt.Errorf("group_chat: 主持人指名 %q 不在名册内（fail-closed）", dec.Next)
+			}
+			return dec.Next, false, nil
+		}
+		return moderator, false, nil
+	}
+	// 上一步是参与者发言 → 主持人接手裁决。
+	return moderator, false, nil
+}
+
+type gcDecision struct {
+	Action string `json:"action"`
+	Next   string `json:"next"`
+}
+
+// gcParseDecision 宽松解析主持人 message.md 里的 JSON 决策（首 `{` 末 `}`）。
+func (e *SquadEngine) gcParseDecision(st *RunState, step *StepSpec) (*gcDecision, error) {
+	msg := e.gcMessageOf(st, step)
+	start := strings.Index(msg, "{")
+	end := strings.LastIndex(msg, "}")
+	if start < 0 || end <= start {
+		return nil, fmt.Errorf("group_chat: 主持人输出无 JSON 决策（fail-closed）：%q", truncateStr(msg, 80))
+	}
+	var dec gcDecision
+	if err := json.Unmarshal([]byte(msg[start:end+1]), &dec); err != nil {
+		return nil, fmt.Errorf("group_chat: 主持人决策解析失败（fail-closed）: %v", err)
+	}
+	if dec.Action == "close" {
+		return &dec, nil
+	}
+	if strings.TrimSpace(dec.Next) == "" {
+		return nil, fmt.Errorf("group_chat: 主持人决策缺 next/action（fail-closed）")
+	}
+	return &dec, nil
+}
+
+// gcRunTurn 派生一轮发言步骤并执行。
+func (e *SquadEngine) gcRunTurn(ctx context.Context, drv *flowDriver, st *RunState, turns int, speaker string) (*RunResult, *HitlGate, error) {
+	step := StepSpec{
+		ID:           fmt.Sprintf("gc%02d", turns+1),
+		Role:         speaker,
+		Title:        fmt.Sprintf("群聊第 %d 轮：%s 发言（把发言写入 message.md；同意收口就写 [close]）", turns+1, speaker),
+		Targets:      []string{"message.md"},
+		SubWorkspace: fmt.Sprintf("group_chat/turn_%02d_%s", turns+1, speaker),
+		Status:       "pending",
+	}
+	st.mu.Lock()
+	st.Plan.Workflow.Steps = append(st.Plan.Workflow.Steps, step)
+	idx := len(st.Plan.Workflow.Steps) - 1
+	_ = st.save()
+	st.mu.Unlock()
+	return e.gcRunStep(ctx, drv, st, idx)
+}
+
+// gcRunStep 执行一个轮次步骤：过门 → runOneStep → 转录并入共享状态。
+// 挂起（gate）时步骤保持未完，恢复重入经 gcHeldStepIdx 续跑同一步骤。
+func (e *SquadEngine) gcRunStep(ctx context.Context, drv *flowDriver, st *RunState, idx int) (*RunResult, *HitlGate, error) {
+	out, gate, err := drv.gateBeforeRun(ctx, st, idx)
+	if err != nil || gate != nil || out != nil {
+		return out, gate, err
+	}
+	step := st.Plan.Workflow.Steps[idx]
+	drv.emit(st, Event{Type: EvPhase, StepID: step.ID, Role: step.Role,
+		Text: fmt.Sprintf("group_chat：%s 发言（第 %d 轮）", step.Role, e.gcTurnCount(st)+1)})
+	out, gate, err = drv.runOneStep(ctx, st, idx)
+	if err != nil || gate != nil || out != nil {
+		return out, gate, err
+	}
+	// 转录并入共享状态：全量落盘 transcript.md，近端进 BB 字段（下一位
+	// 发言人的 TASK.md 黑板快照可见）。
+	msg := e.gcMessageOf(st, &st.Plan.Workflow.Steps[idx])
+	e.gcAppendTranscript(st, e.gcTurnCount(st), step.Role, msg)
+	return nil, nil, nil
+}
+
+// gcAppendTranscript 追加转录（全量文件 + BB 近端快照）。
+func (e *SquadEngine) gcAppendTranscript(st *RunState, turn int, speaker, msg string) {
+	dir := filepath.Join(st.Meta.WorkDir, "group_chat")
+	_ = os.MkdirAll(dir, 0o755)
+	line := fmt.Sprintf("%d. %s：%s\n", turn, speaker, strings.TrimSpace(msg))
+	f, _ := os.OpenFile(filepath.Join(dir, "transcript.md"), os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o644)
+	if f != nil {
+		_, _ = f.WriteString(line)
+		_ = f.Close()
+	}
+	st.mu.Lock()
+	if st.BB.Fields == nil {
+		st.BB.Fields = map[string]string{}
+	}
+	cur := st.BB.Fields["transcript"] + line
+	if len(cur) > gcTranscriptCapBB {
+		cur = cur[len(cur)-gcTranscriptCapBB:]
+	}
+	st.BB.Fields["transcript"] = cur
+	_ = st.save()
+	st.mu.Unlock()
+}
+
+// gcLastStep 最后一个已完成的派生轮次步骤（主持人决策解析的锚点）。
+func (e *SquadEngine) gcLastStep(st *RunState) *StepSpec {
+	for i := len(st.Plan.Workflow.Steps) - 1; i >= 0; i-- {
+		s := &st.Plan.Workflow.Steps[i]
+		if strings.HasPrefix(s.ID, "gc") && s.Status == "completed" {
+			return s
+		}
+	}
+	return nil
+}
+
+// gcMessageOf 读取某轮的 message.md（缺文件 = 空串）。
+func (e *SquadEngine) gcMessageOf(st *RunState, step *StepSpec) string {
+	data, err := os.ReadFile(filepath.Join(st.Meta.WorkDir, filepath.FromSlash(step.SubWorkspace), "message.md"))
+	if err != nil {
+		return ""
+	}
+	return string(data)
+}
+
+// gcMessageClosed 第 idx 步的发言是否带收口标记。
+func (e *SquadEngine) gcMessageClosed(st *RunState, idx int) bool {
+	if idx < 0 || idx >= len(st.Plan.Workflow.Steps) {
+		return false
+	}
+	msg := e.gcMessageOf(st, &st.Plan.Workflow.Steps[idx])
+	return strings.Contains(strings.ToLower(msg), gcCloseMarker)
+}
+
+// gcFinish 收口：交付物 = 全量转录；写 output.md；状态落盘；构造结果。
+func (e *SquadEngine) gcFinish(st *RunState, drv *flowDriver) *RunResult {
+	transcript := ""
+	if data, err := os.ReadFile(filepath.Join(st.Meta.WorkDir, "group_chat", "transcript.md")); err == nil {
+		transcript = string(data)
+	}
+	report := "# 群聊转录\n\n" + transcript
+	_ = os.WriteFile(filepath.Join(st.Meta.WorkDir, "output.md"), []byte(report), 0o644)
+	turns := e.gcTurnCount(st)
+	st.mu.Lock()
+	wf := st.Workflow()
+	wf.Status = string(RunCompleted)
+	st.setWorkflow(wf)
+	st.Meta.Status = string(RunCompleted)
+	now := time.Now()
+	st.Meta.CompletedAt = &now
+	_ = st.save()
+	st.mu.Unlock()
+	summary := fmt.Sprintf("group_chat：%d 轮发言，转录已收口", turns)
+	drv.emit(st, Event{Type: EvPhase, Text: summary})
+	return &RunResult{RunID: st.Meta.ID, Status: RunCompleted, Plan: planPtr(st),
+		Deliverable: "output.md", Summary: summary, WorkDir: st.Meta.WorkDir}
+}
+
+func truncateStr(s string, n int) string {
+	if len(s) <= n {
+		return s
+	}
+	return s[:n] + "…"
+}

squad/handoff.go

@@ -0,0 +1,91 @@
+package squad
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+// handoff.go — handoff 跨拓扑原语（Q2 WP3）。
+// 语义（计划 §三 WP3）：StepSpec.Handoff 非空的步骤完成后，最终答案所有权
+// 移交给目标角色——① 记录所有权转移（Handoffs，随 RunState 持久化）；
+// ② 目标角色的下一个步骤收到「过滤历史」：只带移交步骤的主产出，不带全量
+// 转录（一次性并入任务书，与 mailbox 同款机制）；③ finalize 汇总交付物时
+// 取链尾（最后一次移交的目标角色）的最后一个完成步骤产出，而非全图最后
+// 完成步骤。目标角色不在小队内 = fail-closed（步骤启动前拒绝）。
+
+// HandoffRecord 是一次所有权转移记录。
+type HandoffRecord struct {
+	FromRole  string    `json:"from_role"`
+	FromStep  string    `json:"from_step"`
+	ToRole    string    `json:"to_role"`
+	Output    string    `json:"output,omitempty"` // 移交步骤主产出（截断上限内）
+	At        time.Time `json:"at"`
+	Delivered bool      `json:"delivered,omitempty"`
+}
+
+// handoffOutputCap 移交上下文的产出截断上限（过滤历史：只带主产出，且限量）。
+const handoffOutputCap = 64 * 1024
+
+// takeHandoffFor 取出移交给某角色的未投递记录，标记已投递（一次性）。
+// 调用方负责随后 st.save()（或在临界区内）。
+func takeHandoffFor(st *RunState, role string) *HandoffRecord {
+	for i := range st.Handoffs {
+		h := &st.Handoffs[i]
+		if h.Delivered || h.ToRole != role {
+			continue
+		}
+		h.Delivered = true
+		out := *h
+		return &out
+	}
+	return nil
+}
+
+// formatHandoffSection 渲染任务书里的移交上下文段（无则空串）。
+func formatHandoffSection(h *HandoffRecord) string {
+	if h == nil {
+		return ""
+	}
+	body := h.Output
+	if len(body) > handoffOutputCap {
+		body = body[:handoffOutputCap] + "\n…（已截断）"
+	}
+	var b strings.Builder
+	fmt.Fprintf(&b, "\n\n## 移交上下文（所有权来自 %s，步骤 %s）\n", h.FromRole, h.FromStep)
+	b.WriteString("以下是移交方的主产出（过滤历史：只含该产出，不含其过程转录）：\n\n")
+	b.WriteString(body)
+	b.WriteString("\n")
+	return b.String()
+}
+
+// handoffChainTail 返回移交链尾角色（无移交记录返回空串）。
+func handoffChainTail(st *RunState) string {
+	if n := len(st.Handoffs); n > 0 {
+		return st.Handoffs[n-1].ToRole
+	}
+	return ""
+}
+
+// recordHandoff 步骤完成时的所有权转移记录：主产出快照（截断上限内）+
+// 持久化 + 事件。目标角色合法性已在步骤启动前 fail-closed 校验。
+func (d *flowDriver) recordHandoff(st *RunState, step StepSpec, subDir string, targets []string) {
+	output := ""
+	if data, err := os.ReadFile(filepath.Join(subDir, firstTarget(targets))); err == nil {
+		output = string(data)
+	}
+	if len(output) > handoffOutputCap {
+		output = output[:handoffOutputCap] + "\n…（已截断）"
+	}
+	st.mu.Lock()
+	st.Handoffs = append(st.Handoffs, HandoffRecord{
+		FromRole: step.Role, FromStep: step.ID, ToRole: step.Handoff,
+		Output: output, At: time.Now(),
+	})
+	_ = st.save()
+	st.mu.Unlock()
+	d.emit(st, Event{Type: EvPhase, StepID: step.ID, Role: step.Role,
+		Text: fmt.Sprintf("handoff：%s → %s（最终答案所有权移交）", step.Role, step.Handoff)})
+}

squad/models.go

@@ -128,6 +128,10 @@ type StepSpec struct {
 	Branches []Branch `json:"branches,omitempty"`
 	// Handoff 非空 = 完成即把最终答案所有权移交给该角色（Q2 handoff 原语）。
 	Handoff string `json:"handoff,omitempty"`
+	// Brief 编译期任务指令（Q3 编译器）：非空时渲染进 TASK.md 的
+	// 「任务指令」节，位于标题/产出之后、上下文表之前。图步的富文本任务书
+	// 载体（此前只有 leader 委派有 briefing）。
+	Brief string `json:"brief,omitempty"`
 }
 
 // LoopSpec 是循环步的预算与停机条件（Q2）。

squad/review.go

@@ -0,0 +1,366 @@
+package squad
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+)
+
+// review.go — review 拓扑驱动（Q2 WP3，验收二）。
+// 与 backend internal/runtime/review.go 的 runReview 等价：
+// 并行 N finder（semaphore 3）→ 宽松 JSON 解析（首 `[` 末 `]`，丢空 issue）
+// → 按 (location,issue) 去重、上限 10 → 每条独立 verifier（尾行
+// VERDICT: PASS/FAIL/PARTIAL）→ 只留 PASS（fail-closed）→ severity 稳定排序
+// → 报告恒带「已丢弃 N 条未验证」。解析/去重/判定/排序/文案与 backend 同一
+// 格式串（计划 §一.5：以报告字节形态为等价判据）。
+//
+// squad 侧接线：finder = 计划步骤（各自的 findings.json 为目标产物，经
+// runOneStep 走完整工作区/事件/HITL 机制）；verifier = 驱动内按 verify 角色
+// 直接 Execute 的核实调用（对应 backend 的 spawn(verifyProfileID,…)），
+// 每次核实落盘 reviews/verify_NN/ 留痕。
+
+func init() {
+	_ = RegisterTopologyDriver(TopologyReview)
+}
+
+// reviewFinding 与 backend reviewFinding 同构（JSON 键一致）。
+type reviewFinding struct {
+	Location string `json:"location"`
+	Severity string `json:"severity"`
+	Issue    string `json:"issue"`
+	Evidence string `json:"evidence"`
+}
+
+// reviewVerbatimTask 是核实调用的任务文案（与 backend runReview 同串）。
+const reviewVerbatimTask = "独立核实这条问题是否成立。材料如下：\n%s\n\n问题：%s\n只在结尾给出一行 VERDICT: PASS、FAIL 或 PARTIAL。"
+
+// parseFindings 宽松解析：首 `[` 末 `]`，丢空 issue（backend 同款）。
+func parseFindings(text string) []reviewFinding {
+	start := strings.Index(text, "[")
+	end := strings.LastIndex(text, "]")
+	if start < 0 || end <= start {
+		return nil
+	}
+	var out []reviewFinding
+	if err := json.Unmarshal([]byte(text[start:end+1]), &out); err != nil {
+		return nil
+	}
+	var kept []reviewFinding
+	for _, f := range out {
+		if strings.TrimSpace(f.Issue) == "" {
+			continue
+		}
+		kept = append(kept, f)
+	}
+	return kept
+}
+
+// dedupeFindings 按 (location,issue) 去重，上限 limit（backend 同款）。
+func dedupeFindings(groups [][]reviewFinding, limit int) []reviewFinding {
+	seen := map[string]bool{}
+	var out []reviewFinding
+	for _, group := range groups {
+		for _, f := range group {
+			key := strings.TrimSpace(f.Location) + "\n" + strings.TrimSpace(f.Issue)
+			if seen[key] {
+				continue
+			}
+			seen[key] = true
+			out = append(out, f)
+			if len(out) >= limit {
+				return out
+			}
+		}
+	}
+	return out
+}
+
+// reviewVerdict 尾行 VERDICT 判定（backend 同款：PASS/FAIL/PARTIAL，
+// 解析不出 = 空串 = 不通过）。
+func reviewVerdict(text string) string {
+	lines := strings.Split(text, "\n")
+	for i := len(lines) - 1; i >= 0; i-- {
+		line := strings.TrimSpace(lines[i])
+		if line == "" || !strings.HasPrefix(strings.ToUpper(line), "VERDICT:") {
+			continue
+		}
+		v := strings.TrimSpace(line[len("VERDICT:"):])
+		v = strings.ToUpper(v)
+		switch {
+		case strings.HasPrefix(v, "PASS"):
+			return "PASS"
+		case strings.HasPrefix(v, "FAIL"):
+			return "FAIL"
+		case strings.HasPrefix(v, "PARTIAL"):
+			return "PARTIAL"
+		default:
+			return ""
+		}
+	}
+	return ""
+}
+
+// severityRank 稳定排序键（backend 同款）。
+func severityRank(s string) int {
+	switch strings.ToLower(strings.TrimSpace(s)) {
+	case "critical":
+		return 0
+	case "high":
+		return 1
+	case "medium":
+		return 2
+	case "low":
+		return 3
+	default:
+		return 4
+	}
+}
+
+// reviewParallel semaphore-3 并行（backend parallel 同款）。
+func reviewParallel(n int, fn func(i int)) {
+	if n <= 0 {
+		return
+	}
+	sem := make(chan struct{}, 3)
+	var wg sync.WaitGroup
+	for i := 0; i < n; i++ {
+		wg.Add(1)
+		go func(i int) {
+			defer wg.Done()
+			sem <- struct{}{}
+			defer func() { <-sem }()
+			fn(i)
+		}(i)
+	}
+	wg.Wait()
+}
+
+// runReviewDriver review 拓扑入口。finder 阶段复用计划步骤（可挂起可恢复：
+// 重入时已完成步骤不重跑，findings.json 从各自子工作区读取）。
+func (e *SquadEngine) runReviewDriver(ctx context.Context, st *RunState) (*RunResult, error) {
+	drv := &flowDriver{opts: e.deps}
+	steps := st.Plan.Workflow.Steps
+
+	// verify 角色先行解析（fail-fast：缺角色不浪费 finder 轮次）。
+	verifyRoleName := orDefault(st.Meta.Metadata["review_verify_role"], "verifier")
+	verifyRole, ok := findAgent(st.Plan.Squad.Agents, verifyRoleName)
+	if !ok {
+		if r, exists := e.deps.Registry.Get(verifyRoleName); exists {
+			verifyRole, ok = r, true
+		}
+	}
+	if !ok {
+		return e.driverFail(st, fmt.Sprintf("review: verify 角色 %q 不在小队内（fail-closed）", verifyRoleName)), nil
+	}
+	verifyBackend, _, rerr := e.deps.Backends.Resolve(verifyRole, st.Meta.Backend)
+	if rerr != nil {
+		return e.driverFail(st, "review: verify 后端解析失败: "+rerr.Error()), nil
+	}
+
+	// 1) finder 阶段：先全组过门（任一要挂起则整组不执行，与 advance 并行组
+	// 同款语义），再 semaphore-3 并行执行。
+	var finderIdx []int
+	for i := range steps {
+		if steps[i].Status == "pending" || steps[i].Status == "running" {
+			finderIdx = append(finderIdx, i)
+		}
+	}
+	for _, idx := range finderIdx {
+		out, gate, err := drv.gateBeforeRun(ctx, st, idx)
+		if err != nil {
+			return nil, err
+		}
+		if gate != nil {
+			if out == nil {
+				out = heldResult(st, gate)
+			}
+			return out, nil
+		}
+		if out != nil {
+			return out, nil
+		}
+	}
+	drv.emit(st, Event{Type: EvPhase, Text: fmt.Sprintf("review：%d 个 finder 并行找问题", len(finderIdx))})
+	var holdGate *HitlGate
+	var holdOut *RunResult
+	var fatal *RunResult
+	finderFailed := 0
+	var fmu sync.Mutex
+	reviewParallel(len(finderIdx), func(k int) {
+		idx := finderIdx[k]
+		out, gate, err := drv.runOneStep(ctx, st, idx)
+		fmu.Lock()
+		defer fmu.Unlock()
+		if err != nil {
+			if fatal == nil {
+				fatal = &RunResult{RunID: st.Meta.ID, Status: RunFailed, Plan: planPtr(st),
+					Error: err.Error(), WorkDir: st.Meta.WorkDir}
+			}
+			return
+		}
+		if gate != nil && holdGate == nil {
+			holdGate = gate
+			holdOut = out
+			return
+		}
+		if out != nil && out.Status == RunFailed && fatal == nil {
+			fatal = out // 关键 finder 失败：fail-closed 传播
+			return
+		}
+		if st.Plan.Workflow.Steps[idx].Status == "failed" {
+			finderFailed++ // 非关键 finder 失败：宽容（backend spawn err 同款），收口降级
+		}
+	})
+	if fatal != nil {
+		return fatal, nil
+	}
+	if holdGate != nil {
+		if holdOut == nil {
+			holdOut = heldResult(st, holdGate)
+		}
+		return holdOut, nil
+	}
+
+	// 2) 收集各 finder 的 findings.json（宽松解析；缺文件/坏 JSON = 该 finder
+	// 零发现，与 backend 同款）。
+	steps = st.Plan.Workflow.Steps
+	groups := make([][]reviewFinding, 0, len(steps))
+	for i := range steps {
+		if steps[i].Status != "completed" {
+			continue
+		}
+		subDir := filepath.Join(st.Meta.WorkDir, filepath.FromSlash(steps[i].SubWorkspace))
+		data, err := os.ReadFile(filepath.Join(subDir, "findings.json"))
+		if err != nil {
+			continue
+		}
+		groups = append(groups, parseFindings(string(data)))
+	}
+	unique := dedupeFindings(groups, 10)
+	drv.emit(st, Event{Type: EvPhase, Text: fmt.Sprintf("review：去重后 %d 条，逐条独立核实", len(unique))})
+
+	// 3) 逐条 verify（semaphore-3 并行；fail-closed：核实调用失败/无判定 = 丢弃）。
+	target := reviewTargetMaterial(st)
+	kept := make([]reviewFinding, len(unique))
+	pass := make([]bool, len(unique))
+	reviewParallel(len(unique), func(i int) {
+		f := unique[i]
+		body, _ := json.Marshal(f)
+		task := fmt.Sprintf(reviewVerbatimTask, target, body)
+		vDir := filepath.Join(st.Meta.WorkDir, "reviews", fmt.Sprintf("verify_%02d", i+1))
+		if err := os.MkdirAll(vDir, 0o755); err != nil {
+			return
+		}
+		instructions := ""
+		if e.deps.Workspaces != nil {
+			instructions = e.deps.Workspaces.ResolveInstructions(verifyRole)
+		}
+		res, err := verifyBackend.Execute(ctx, ExecRequest{
+			WorkDir:      vDir,
+			Prompt:       task,
+			Instructions: instructions,
+			Targets:      []string{"verdict.md"},
+			Timeout:      e.deps.StepTimeout,
+			SessionScope: st.Meta.ID + "/verify_" + fmt.Sprintf("%02d", i+1),
+		})
+		if err != nil || res == nil {
+			return
+		}
+		text := string(res.Patches["verdict.md"]) + "\n" + res.Logs
+		if data, rerr2 := os.ReadFile(filepath.Join(vDir, "verdict.md")); rerr2 == nil {
+			text = string(data) + "\n" + text
+		}
+		if reviewVerdict(text) == "PASS" {
+			kept[i] = f
+			pass[i] = true
+		}
+	})
+	var verified []reviewFinding
+	for i, ok := range pass {
+		if ok {
+			verified = append(verified, kept[i])
+		}
+	}
+
+	// 4) severity 稳定排序 + 等价报告（backend 同格式串）。
+	sort.SliceStable(verified, func(i, j int) bool {
+		return severityRank(verified[i].Severity) < severityRank(verified[j].Severity)
+	})
+	dropped := len(unique) - len(verified)
+	var b strings.Builder
+	if len(verified) == 0 {
+		b.WriteString("没有验证通过的问题。\n")
+	}
+	for _, f := range verified {
+		fmt.Fprintf(&b, "- [%s] %s：%s\n  证据：%s\n",
+			orDefault(f.Severity, "medium"), orDefault(f.Location, "未定位"), f.Issue, f.Evidence)
+	}
+	fmt.Fprintf(&b, "已丢弃 %d 条未验证\n", dropped)
+	report := b.String()
+
+	// 5) 收口：报告落盘（reviews/report.md + output.md 交付物约定），
+	// finder 有失败则降级（诚实信号），否则完成。
+	reviewsDir := filepath.Join(st.Meta.WorkDir, "reviews")
+	_ = os.MkdirAll(reviewsDir, 0o755)
+	_ = os.WriteFile(filepath.Join(reviewsDir, "report.md"), []byte(report), 0o644)
+	_ = os.WriteFile(filepath.Join(st.Meta.WorkDir, "output.md"), []byte(report), 0o644)
+	st.mu.Lock()
+	if st.BB.Fields == nil {
+		st.BB.Fields = map[string]string{}
+	}
+	st.BB.Fields["review_verified"] = fmt.Sprintf("%d", len(verified))
+	st.BB.Fields["review_dropped"] = fmt.Sprintf("%d", dropped)
+	wf := st.Workflow()
+	status := RunCompleted
+	if finderFailed > 0 {
+		status = RunDegraded
+	}
+	wf.Status = string(status)
+	st.setWorkflow(wf)
+	st.Meta.Status = string(status)
+	now := time.Now()
+	st.Meta.CompletedAt = &now
+	_ = st.save()
+	st.mu.Unlock()
+	summary := fmt.Sprintf("review：保留 %d 条 / 丢弃 %d 条未验证", len(verified), dropped)
+	if finderFailed > 0 {
+		summary += fmt.Sprintf("（%d 个 finder 失败，降级）", finderFailed)
+	}
+	drv.emit(st, Event{Type: EvPhase, Text: summary})
+	return &RunResult{RunID: st.Meta.ID, Status: status, Plan: planPtr(st),
+		Deliverable: "output.md", Summary: summary, WorkDir: st.Meta.WorkDir}, nil
+}
+
+// reviewTargetMaterial 取被评审材料：元数据 review_target 优先，
+// 其次运行目标（context/goal.md）。
+func reviewTargetMaterial(st *RunState) string {
+	if v := strings.TrimSpace(st.Meta.Metadata["review_target"]); v != "" {
+		return v
+	}
+	if data, err := os.ReadFile(filepath.Join(st.Meta.WorkDir, "context", "goal.md")); err == nil {
+		return string(data)
+	}
+	return ""
+}
+
+// driverFail 驱动级 fail-closed 收口（与 leaderFail 同款语义）。
+func (e *SquadEngine) driverFail(st *RunState, reason string) *RunResult {
+	now := time.Now()
+	st.mu.Lock()
+	st.Meta.Status = string(RunFailed)
+	st.Meta.CompletedAt = &now
+	wf := st.Workflow()
+	wf.Status = "failed"
+	st.setWorkflow(wf)
+	_ = st.save()
+	st.mu.Unlock()
+	(&flowDriver{opts: e.deps}).emit(st, Event{Type: EvPhase, Text: reason})
+	return &RunResult{RunID: st.Meta.ID, Status: RunFailed, Plan: planPtr(st),
+		Error: reason, WorkDir: st.Meta.WorkDir}
+}

squad/runstate.go

@@ -30,6 +30,12 @@ type RunState struct {
 	// Mailbox 运行内点对点消息（Q2）：随 RunState 持久化；只在步骤启动时
 	// 并入任务书，永不触碰 HITL 门。
 	Mailbox []MailMessage `json:"mailbox,omitempty"`
+	// Handoffs 所有权转移记录（Q2 handoff 原语）：随 RunState 持久化；
+	// 目标角色的下一步骤一次性接收移交上下文，finalize 取链尾产出。
+	Handoffs []HandoffRecord `json:"handoffs,omitempty"`
+	// Board task_board 拓扑的队列状态（Q2）：claim/lease/complete 三原语，
+	// 随 RunState 持久化；孤儿租约在驱动重入时再武装。
+	Board []BoardTask `json:"board,omitempty"`
 	// Usage 按角色累计的 token 用量。
 	Usage map[string]*Usage `json:"usage,omitempty"`
 	// Leader leader-delegation 模式的循环状态（workspace 内 leader.json 持久化）。
@@ -96,6 +102,8 @@ func (st *RunState) persist() error {
 		RepairBudgetGranted:   st.RepairBudgetGranted,
 		Clarifications:        st.Clarifications,
 		Mailbox:               st.Mailbox,
+		Handoffs:              st.Handoffs,
+		Board:                 st.Board,
 	})
 }
 
@@ -105,6 +113,8 @@ type diskRunState struct {
 	RepairBudgetGranted   int             `json:"repair_budget_granted,omitempty"`
 	Clarifications        []string        `json:"clarifications,omitempty"`
 	Mailbox               []MailMessage   `json:"mailbox,omitempty"`
+	Handoffs              []HandoffRecord `json:"handoffs,omitempty"`
+	Board                 []BoardTask     `json:"board,omitempty"`
 }
 
 // Workflow 返回计划的编排清单（简洁访问器）。
@@ -160,6 +170,8 @@ func loadRunState(wsDir string) (*RunState, error) {
 		st.RepairBudgetGranted = disk.RepairBudgetGranted
 		st.Clarifications = disk.Clarifications
 		st.Mailbox = disk.Mailbox
+		st.Handoffs = disk.Handoffs
+		st.Board = disk.Board
 	} else if !os.IsNotExist(err) {
 		return nil, err
 	}

squad/taskboard.go

@@ -0,0 +1,308 @@
+package squad
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"time"
+)
+
+// taskboard.go — task_board 拓扑驱动（Q2 WP4）。
+// 形态：计划步骤 = 板上任务（Needs = 依赖门）；执行语义是队列化的
+// claim/lease/complete 三原语——工作者认领任务（带租约时限）、执行、完成；
+// 进程死亡留下的孤儿租约（claimed 且租约过期）在驱动重入时再武装回 open
+// （Attempts 保留，超限由步骤级重试护栏兜底）。全部任务收口后走标准
+// finalize（交付物/质检/降级判定与图拓扑同一收口面）。
+// 挂起（HITL）安全：claimed 且步骤未完的任务在重入时续跑，不重复认领。
+
+func init() {
+	_ = RegisterTopologyDriver(TopologyTaskBoard)
+}
+
+// DefaultTaskLeaseSeconds 任务租约缺省时限（秒）。
+const DefaultTaskLeaseSeconds = 600
+
+// boardSkipReason 依赖门无法满足（上游 failed/skipped）时的跳过原因。
+const boardSkipReason = "task_board: 依赖未满足（上游失败或跳过）"
+
+// BoardTask 是任务板上一条任务的队列状态。
+type BoardTask struct {
+	ID        string `json:"id"`
+	Status    string `json:"status"` // open / claimed / done / failed / skipped
+	ClaimedBy string `json:"claimed_by,omitempty"`
+	// LeaseExpires 认领租约到期时刻；过期未 complete = 孤儿租约，重入再武装。
+	LeaseExpires time.Time `json:"lease_expires,omitempty"`
+	// Attempts 认领次数（孤儿再武装累加；执行重试由步骤级护栏负责）。
+	Attempts int `json:"attempts,omitempty"`
+}
+
+// runTaskBoardDriver task_board 拓扑入口（幂等可恢复）。
+func (e *SquadEngine) runTaskBoardDriver(ctx context.Context, st *RunState) (*RunResult, error) {
+	drv := &flowDriver{opts: e.deps}
+	e.initBoard(st)
+	e.rearmOrphanLeases(st)
+	leaseTTL := DefaultTaskLeaseSeconds
+	if v := st.Meta.Metadata["task_board_lease_seconds"]; v != "" {
+		if n := parseIntDefault(v, DefaultTaskLeaseSeconds); n > 0 {
+			leaseTTL = n
+		}
+	}
+
+	for {
+		idx, held := e.boardHeldTask(st)
+		if !held {
+			var ok bool
+			idx, ok = e.boardClaimNext(st, leaseTTL)
+			if !ok {
+				// 无可认领：把依赖已死（上游 failed/skipped）的 open 任务级联
+				// 置 skipped；再无变化则收口。
+				if !e.boardSkipDeadlocked(st) {
+					break
+				}
+				continue
+			}
+		}
+		out, gate, err := e.boardRunTask(ctx, drv, st, idx)
+		if err != nil {
+			return nil, err
+		}
+		if gate != nil {
+			if out == nil {
+				out = heldResult(st, gate)
+			}
+			return out, nil
+		}
+		if out != nil { // 关键任务失败：fail-closed 传播（failStep 已置运行失败）
+			return out, nil
+		}
+		e.boardSettleTask(st, idx)
+	}
+	return e.boardFinish(ctx, drv, st)
+}
+
+// initBoard 首次进入时从计划步骤派生任务板（恢复重入直读持久化状态）。
+func (e *SquadEngine) initBoard(st *RunState) {
+	st.mu.Lock()
+	defer st.mu.Unlock()
+	if len(st.Board) > 0 {
+		return
+	}
+	for _, s := range st.Plan.Workflow.Steps {
+		status := "open"
+		switch s.Status {
+		case "completed":
+			status = "done"
+		case "failed":
+			status = "failed"
+		case "skipped":
+			status = "skipped"
+		}
+		st.Board = append(st.Board, BoardTask{ID: s.ID, Status: status})
+	}
+	_ = st.save()
+}
+
+// rearmOrphanLeases 孤儿租约再武装：claimed 且租约过期 → open（进程死亡
+// 恢复路径；Attempts 保留作观测）。
+func (e *SquadEngine) rearmOrphanLeases(st *RunState) {
+	now := time.Now()
+	st.mu.Lock()
+	var rearmed []string
+	for i := range st.Board {
+		t := &st.Board[i]
+		if t.Status == "claimed" && !t.LeaseExpires.IsZero() && t.LeaseExpires.Before(now) {
+			t.Status = "open"
+			t.ClaimedBy = ""
+			rearmed = append(rearmed, t.ID)
+		}
+	}
+	changed := len(rearmed) > 0
+	if changed {
+		_ = st.save()
+	}
+	st.mu.Unlock()
+	if changed {
+		(&flowDriver{opts: e.deps}).emit(st, Event{Type: EvPhase,
+			Text: fmt.Sprintf("task_board：孤儿租约再武装 %s", strings.Join(rearmed, ","))})
+	}
+}
+
+// boardHeldTask 返回 claimed 且步骤未完的任务（HITL 挂起/中断重入的续跑点）。
+func (e *SquadEngine) boardHeldTask(st *RunState) (int, bool) {
+	for ti := range st.Board {
+		t := &st.Board[ti]
+		if t.Status != "claimed" {
+			continue
+		}
+		if idx, s := e.boardStep(st, t.ID); idx >= 0 && (s.Status == "pending" || s.Status == "running") {
+			return idx, true
+		}
+	}
+	return -1, false
+}
+
+// boardClaimNext 认领下一个可执行任务（open 且依赖门全 done），返回步骤下标。
+func (e *SquadEngine) boardClaimNext(st *RunState, leaseTTL int) (int, bool) {
+	st.mu.Lock()
+	defer st.mu.Unlock()
+	for ti := range st.Board {
+		t := &st.Board[ti]
+		if t.Status != "open" {
+			continue
+		}
+		if !e.boardDepsDoneLocked(st, t.ID) {
+			continue
+		}
+		idx, s := e.boardStepLocked(st, t.ID)
+		if idx < 0 {
+			continue
+		}
+		t.Status = "claimed"
+		t.ClaimedBy = s.Role
+		t.Attempts++
+		t.LeaseExpires = time.Now().Add(time.Duration(leaseTTL) * time.Second)
+		_ = st.save()
+		(&flowDriver{opts: e.deps}).emit(st, Event{Type: EvPhase, StepID: t.ID, Role: s.Role,
+			Text: fmt.Sprintf("task_board：%s 认领 %s（租约 %ds，第 %d 次）", s.Role, t.ID, leaseTTL, t.Attempts)})
+		return idx, true
+	}
+	return -1, false
+}
+
+// boardSkipDeadlocked 把依赖已死（上游 failed/skipped）的 open 任务级联置
+// skipped；返回是否有变化（有则继续循环级联）。
+func (e *SquadEngine) boardSkipDeadlocked(st *RunState) bool {
+	st.mu.Lock()
+	changed := false
+	for ti := range st.Board {
+		t := &st.Board[ti]
+		if t.Status != "open" {
+			continue
+		}
+		if e.boardDepsDeadLocked(st, t.ID) {
+			t.Status = "skipped"
+			if idx, s := e.boardStepLocked(st, t.ID); idx >= 0 {
+				s.Status = "skipped"
+				s.Error = boardSkipReason
+				st.Plan.Workflow.Steps[idx] = *s
+			}
+			changed = true
+		}
+	}
+	if changed {
+		_ = st.save()
+	}
+	st.mu.Unlock()
+	return changed
+}
+
+// boardRunTask 执行已认领任务：过门 → runOneStep。
+func (e *SquadEngine) boardRunTask(ctx context.Context, drv *flowDriver, st *RunState, idx int) (*RunResult, *HitlGate, error) {
+	out, gate, err := drv.gateBeforeRun(ctx, st, idx)
+	if err != nil || gate != nil || out != nil {
+		return out, gate, err
+	}
+	return drv.runOneStep(ctx, st, idx)
+}
+
+// boardSettleTask 任务结算：步骤 completed → done；failed（非关键降级）→ failed。
+func (e *SquadEngine) boardSettleTask(st *RunState, idx int) {
+	step := st.Plan.Workflow.Steps[idx]
+	status := "done"
+	if step.Status == "failed" {
+		status = "failed"
+	}
+	st.mu.Lock()
+	for i := range st.Board {
+		if st.Board[i].ID == step.ID {
+			st.Board[i].Status = status
+			st.Board[i].LeaseExpires = time.Time{}
+		}
+	}
+	_ = st.save()
+	st.mu.Unlock()
+	(&flowDriver{opts: e.deps}).emit(st, Event{Type: EvPhase, StepID: step.ID, Role: step.Role,
+		Text: fmt.Sprintf("task_board：%s → %s", step.ID, status)})
+}
+
+// boardFinish 全部任务收口后走标准 finalize（交付物/质检/降级与图拓扑同面）。
+// 仍有 open/claimed 任务 = 依赖不可满足，fail-closed 不静默收口。
+func (e *SquadEngine) boardFinish(ctx context.Context, drv *flowDriver, st *RunState) (*RunResult, error) {
+	done, total := 0, len(st.Board)
+	for _, t := range st.Board {
+		switch t.Status {
+		case "done":
+			done++
+		case "open", "claimed":
+			return e.driverFail(st, fmt.Sprintf("task_board: 任务 %s 无法收口（依赖不可满足）", t.ID)), nil
+		}
+	}
+	drv.emit(st, Event{Type: EvPhase, Text: fmt.Sprintf("task_board：收口（done %d/%d）", done, total)})
+	out, gate, err := drv.finalize(ctx, st)
+	if err != nil {
+		return nil, err
+	}
+	if gate != nil {
+		return heldResult(st, gate), nil
+	}
+	return out, nil
+}
+
+// boardStep 按任务 ID 找步骤（只读副本）。
+func (e *SquadEngine) boardStep(st *RunState, id string) (int, *StepSpec) {
+	st.mu.Lock()
+	defer st.mu.Unlock()
+	return e.boardStepLocked(st, id)
+}
+
+// boardStepLocked 按任务 ID 找步骤（调用方持锁）。返回下标与副本指针。
+func (e *SquadEngine) boardStepLocked(st *RunState, id string) (int, *StepSpec) {
+	for i := range st.Plan.Workflow.Steps {
+		if st.Plan.Workflow.Steps[i].ID == id {
+			s := st.Plan.Workflow.Steps[i]
+			return i, &s
+		}
+	}
+	return -1, nil
+}
+
+// boardDepsDoneLocked 依赖门：Needs 全部 done（调用方持锁）。
+func (e *SquadEngine) boardDepsDoneLocked(st *RunState, id string) bool {
+	needs := e.boardNeedsLocked(st, id)
+	for _, dep := range needs {
+		found := false
+		for i := range st.Board {
+			if st.Board[i].ID == dep {
+				found = true
+				if st.Board[i].Status != "done" {
+					return false
+				}
+			}
+		}
+		if !found {
+			return false // 依赖不在板上 = fail-closed 不认领
+		}
+	}
+	return true
+}
+
+// boardDepsDeadLocked 依赖已死：任一 Need 为 failed/skipped（级联跳过依据）。
+func (e *SquadEngine) boardDepsDeadLocked(st *RunState, id string) bool {
+	for _, dep := range e.boardNeedsLocked(st, id) {
+		for i := range st.Board {
+			if st.Board[i].ID == dep && (st.Board[i].Status == "failed" || st.Board[i].Status == "skipped") {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+func (e *SquadEngine) boardNeedsLocked(st *RunState, id string) []string {
+	for i := range st.Plan.Workflow.Steps {
+		if st.Plan.Workflow.Steps[i].ID == id {
+			return st.Plan.Workflow.Steps[i].Needs
+		}
+	}
+	return nil
+}

squad/topology_conformance_test.go

@@ -384,9 +384,8 @@ func TestTopologyValidationFailsClosed(t *testing.T) {
 		{"未注册名", "bogus_topology", "未知拓扑"},
 		{"primitive 单跑", TopologyMailbox, "跨拓扑原语"},
 		{"primitive 单跑 handoff", TopologyHandoff, "跨拓扑原语"},
-		{"driver 未点亮", TopologyReview, "驱动未注册"},
-		{"driver 未点亮 group_chat", TopologyGroupChat, "驱动未注册"},
-		{"driver 未点亮 task_board", TopologyTaskBoard, "驱动未注册"},
+		// review/group_chat（WP3）与 task_board（WP4）驱动均已点亮；
+		// 12/12 受理面由 TestTopologyConformance_allTwelve 汇总钉住。
 	}
 	for _, tc := range cases {
 		engine := newTopologyEngine(t, mockScriptPlanner(

squad/workflow.go

@@ -279,6 +279,16 @@ func (d *flowDriver) runOneStep(ctx context.Context, st *RunState, idx int) (*Ru
 			return d.failStep(ctx, st, idx)
 		}
 	}
+	// handoff 原语 fail-closed（Q2）：目标角色必须可解析，启动前拒绝。
+	if step.Handoff != "" {
+		if _, ok := findAgent(st.Plan.Squad.Agents, step.Handoff); !ok {
+			if _, exists := d.opts.Registry.Get(step.Handoff); !exists {
+				step.Status, step.Error = "failed", "handoff: 未知目标角色 "+step.Handoff
+				st.setStep(idx, step)
+				return d.failStep(ctx, st, idx)
+			}
+		}
+	}
 	subDir := filepath.Join(st.Meta.WorkDir, filepath.FromSlash(orDefault(step.SubWorkspace, fmt.Sprintf("tasks/%02d_%s", idx+1, step.Role))))
 	if err := os.MkdirAll(subDir, 0o755); err != nil {
 		return nil, nil, err
@@ -313,11 +323,14 @@ func (d *flowDriver) runOneStep(ctx context.Context, st *RunState, idx int) (*Ru
 	// 任务书；只走 prompt 面，永不触碰 HITL 门（验收三构造性保证）。
 	st.mu.Lock()
 	mail := takeMailFor(st, step.Role)
-	if len(mail) > 0 {
+	handoff := takeHandoffFor(st, step.Role)
+	if len(mail) > 0 || handoff != nil {
 		_ = st.save()
 	}
 	st.mu.Unlock()
 	prompt += formatMailSection(mail)
+	// handoff 原语（Q2）：目标角色的步骤接收过滤历史（只带移交方主产出）。
+	prompt += formatHandoffSection(handoff)
 	instructions := readFileOr(filepath.Join(subDir, "AGENTS.md"), d.opts.Workspaces.ResolveInstructions(role))
 
 	var backend Executor
@@ -464,6 +477,12 @@ func (d *flowDriver) runOneStep(ctx context.Context, st *RunState, idx int) (*Ru
 	d.emit(st, Event{Type: EvStepCompleted, StepID: step.ID, Role: step.Role, Text: step.Title,
 		Data: marshalJSON(map[string]any{"duration_ms": step.DurationMs, "targets": targets})})
 
+	// handoff 原语（Q2）：完成即移交最终答案所有权——记录 + 主产出快照，
+	// 供目标角色下一步骤（过滤历史）与 finalize（链尾产出）消费。
+	if step.Handoff != "" {
+		d.recordHandoff(st, step, subDir, targets)
+	}
+
 	// 循环步再武装（Q2 loop）：停机条件不满足且预算未尽 → 本步与 loop.body
 	// 一起重置为 pending；触顶发 loop_exhausted 事件后按完成继续。
 	if step.Loop != nil {
@@ -775,12 +794,21 @@ func (d *flowDriver) finalize(ctx context.Context, st *RunState) (*RunResult, *H
 		}
 	}
 	// 汇总交付物：最后一个 completed 步骤的主产出 → output.md。
+	// handoff 链尾优先（Q2）：有所有权移交时，交付物取链尾角色的最后一个
+	// completed 步骤产出（最终答案所有权在链尾），无则该角色无完成步骤时回落。
 	var srcStep *StepSpec
 	for i := range wf.Steps {
 		if wf.Steps[i].Status == "completed" {
 			srcStep = &wf.Steps[i]
 		}
 	}
+	if tail := handoffChainTail(st); tail != "" {
+		for i := range wf.Steps {
+			if wf.Steps[i].Status == "completed" && wf.Steps[i].Role == tail {
+				srcStep = &wf.Steps[i]
+			}
+		}
+	}
 	if srcStep == nil {
 		wf.Status = "failed"
 		st.setWorkflow(wf)

squad/workspace.go

@@ -189,6 +189,13 @@ func (e *WorkspaceEngine) writeTaskFile(subDir string, step *StepSpec, role Role
 	fmt.Fprintf(&b, "- 角色：%s（%s）\n", role.Name, role.Role)
 	fmt.Fprintf(&b, "- 期望产出：%v\n\n", step.Targets)
 
+	// 编译期任务指令（Q3）：编译器渲染好的富文本任务书，权威仅次于目标。
+	if strings.TrimSpace(step.Brief) != "" {
+		b.WriteString("## 任务指令\n\n")
+		b.WriteString(strings.TrimSpace(step.Brief))
+		b.WriteString("\n\n")
+	}
+
 	b.WriteString("## 任务上下文资源与权威等级（已快照到本目录，只引用本地路径）\n\n")
 	b.WriteString("| 资源路径 | 权威等级 | 用途说明 | 使用与引用指导 |\n|---|---|---|---|\n")
 	b.WriteString("| `context/goal.md` | **authoritative** | 运行目标 | 不可推翻 |\n")

squad/wp3_conformance_test.go

@@ -0,0 +1,452 @@
+package squad
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+)
+
+// wp3_conformance_test.go — Q2 WP3 验收：review 拓扑与 backend runReview 等价
+// （验收二：并行找问题、逐条验证、丢掉未验证）、handoff 原语（所有权转移 +
+// 过滤历史 + finalize 链尾）、group_chat 驱动（轮转/主持人 + 预算停机）。
+
+// ---- review：与 backend review_test.go 同款断言 ----
+
+// reviewScriptBackend finder 目录回放 findings.json（第 3 个进入者放行，钉住
+// 真并发）；verify_* 目录按 prompt 内容回放判定（与 backend 夹具同文案）。
+type reviewScriptBackend struct {
+	mu          sync.Mutex
+	once        sync.Once
+	entered     int
+	verifyCalls int
+	release     chan struct{}
+}
+
+func (b *reviewScriptBackend) Name() string { return "review-script" }
+
+func (b *reviewScriptBackend) Execute(_ context.Context, req ExecRequest) (*ExecResult, error) {
+	key := filepath.Base(filepath.Clean(req.WorkDir))
+	if strings.HasPrefix(key, "verify_") {
+		b.mu.Lock()
+		b.verifyCalls++
+		b.mu.Unlock()
+		verdict := "看不出对错"
+		switch {
+		case strings.Contains(req.Prompt, "无来源"):
+			verdict = "核对原文确实没有来源。\nVERDICT: PASS"
+		case strings.Contains(req.Prompt, "错字"):
+			verdict = "核对后成立。\nVERDICT: PASS"
+		case strings.Contains(req.Prompt, "过期数据"):
+			verdict = "数据仍有效。\nVERDICT: FAIL"
+		}
+		return writeOne(req.WorkDir, "verdict.md", verdict), nil
+	}
+	// finder：三个必须同时在跑（backend review_test.go:16-33 同款门）。
+	b.mu.Lock()
+	b.entered++
+	n := b.entered
+	b.mu.Unlock()
+	if n == 3 {
+		b.once.Do(func() { close(b.release) })
+	}
+	select {
+	case <-b.release:
+	case <-time.After(time.Second):
+		return nil, fmt.Errorf("finders did not run together")
+	}
+	var findings string
+	switch key {
+	case "01_researcher":
+		findings = `[{"location":"第2段","severity":"high","issue":"无来源","evidence":"显然"},{"location":"第1段","severity":"low","issue":"错字","evidence":"的地"},{"location":"表1","severity":"medium","issue":"过期数据","evidence":"2020"}]`
+	case "02_writer":
+		findings = `[{"location":"第2段","severity":"high","issue":"无来源","evidence":"显然"},{"location":"附录","severity":"medium","issue":"数字不一致","evidence":"3 与 4"}]`
+	default:
+		findings = `[{"location":"结尾","severity":"low","issue":"没有结论","evidence":"最后一句"}]`
+	}
+	return writeOne(req.WorkDir, "findings.json", findings), nil
+}
+
+func writeOne(dir, name, content string) *ExecResult {
+	out := filepath.Join(dir, name)
+	_ = os.MkdirAll(filepath.Dir(out), 0o755)
+	_ = os.WriteFile(out, []byte(content), 0o644)
+	return &ExecResult{Success: true, Patches: map[string][]byte{name: []byte(content)}}
+}
+
+func TestTopologyConformance_review(t *testing.T) {
+	be := &reviewScriptBackend{release: make(chan struct{})}
+	sink := &collectSink{}
+	planner := mockScriptPlanner(
+		StepSpec{ID: "f1", Role: "researcher", Title: "评审一", Targets: []string{"findings.json"}},
+		StepSpec{ID: "f2", Role: "writer", Title: "评审二", Targets: []string{"findings.json"}},
+		StepSpec{ID: "f3", Role: "reviewer", Title: "评审三", Targets: []string{"findings.json"}},
+	)
+	planner.Agents = []RoleSpec{
+		{Role: "researcher", Name: "评审一", Backend: "review-script"},
+		{Role: "writer", Name: "评审二", Backend: "review-script"},
+		{Role: "reviewer", Name: "评审三", Backend: "review-script"},
+		{Role: "verifier", Name: "核实", Backend: "review-script"},
+	}
+	engine := newWP3Engine(t, planner, be, sink, []RoleSpec{
+		{Role: "researcher", Name: "评审一", Backend: "review-script"},
+		{Role: "writer", Name: "评审二", Backend: "review-script"},
+		{Role: "reviewer", Name: "评审三", Backend: "review-script"},
+		{Role: "verifier", Name: "核实", Backend: "review-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "评审材料正文"},
+		RunOptions{Topology: TopologyReview, ReviewTarget: "材料正文"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("status = %s err = %v", res.Status, res.Error)
+	}
+	data, err := os.ReadFile(filepath.Join(res.WorkDir, "output.md"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	out := string(data)
+	// 只留 PASS（fail-closed）：无来源/错字保留；FAIL 与无判定丢弃。
+	if !strings.Contains(out, "无来源") || !strings.Contains(out, "错字") ||
+		strings.Contains(out, "数字不一致") || strings.Contains(out, "没有结论") ||
+		strings.Contains(out, "过期数据") {
+		t.Fatalf("filter = %s", out)
+	}
+	// 报告恒带丢弃计数（backend 同格式串）。
+	if !strings.Contains(out, "已丢弃 3 条未验证") {
+		t.Fatalf("dropped = %s", out)
+	}
+	// 去重后逐条验证：verify 调用数 = unique 数 = 5。
+	if be.verifyCalls != 5 {
+		t.Fatalf("verify calls = %d, want 5 after dedupe", be.verifyCalls)
+	}
+	// severity 稳定排序：high(无来源) 在 low(错字) 前。
+	if strings.Index(out, "无来源") > strings.Index(out, "错字") {
+		t.Fatalf("severity order: %s", out)
+	}
+	if sink.countText("review：3 个 finder 并行找问题") != 1 ||
+		sink.countText("review：去重后 5 条") != 1 {
+		t.Fatal("缺 review 阶段事件")
+	}
+}
+
+// verify 角色缺失 → fail-closed。
+func TestReviewVerifyRoleMissingFailsClosed(t *testing.T) {
+	be := &reviewScriptBackend{release: make(chan struct{})}
+	planner := mockScriptPlanner(
+		StepSpec{ID: "f1", Role: "researcher", Title: "评审", Targets: []string{"findings.json"}},
+	)
+	engine := newWP3Engine(t, planner, be, NopSink{}, []RoleSpec{
+		{Role: "researcher", Name: "评审", Backend: "review-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "评审"},
+		RunOptions{Topology: TopologyReview})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunFailed || !strings.Contains(res.Error, "verify 角色") {
+		t.Fatalf("应 fail-closed：%s %q", res.Status, res.Error)
+	}
+}
+
+// ---- handoff 原语 ----
+
+// handoffScriptBackend 记录 prompt 并按目录回放带标记的产出（≥50 字过最小质检）。
+type handoffScriptBackend struct {
+	mu      sync.Mutex
+	prompts map[string][]string
+}
+
+func (b *handoffScriptBackend) Name() string { return "handoff-script" }
+
+func (b *handoffScriptBackend) Execute(_ context.Context, req ExecRequest) (*ExecResult, error) {
+	key := filepath.Base(filepath.Clean(req.WorkDir))
+	b.mu.Lock()
+	b.prompts[key] = append(b.prompts[key], req.Prompt)
+	b.mu.Unlock()
+	pad := "\n\n这是为了满足最小质检长度要求而补充的正文内容，超过五十个字符。"
+	var content string
+	switch key {
+	case "01_researcher":
+		content = "MARK_RESEARCHER 调研笔记。" + pad
+	case "02_writer":
+		content = "MARK_WRITER 终稿。" + pad
+	default:
+		content = "MARK_REVIEWER 评审意见。" + pad
+	}
+	name := "output.md"
+	if len(req.Targets) > 0 {
+		name = req.Targets[0]
+	}
+	return writeOne(req.WorkDir, name, content), nil
+}
+
+func TestTopologyConformance_handoff(t *testing.T) {
+	be := &handoffScriptBackend{prompts: map[string][]string{}}
+	sink := &collectSink{}
+	engine := newWP3Engine(t, mockScriptPlanner(
+		StepSpec{ID: "s1", Role: "researcher", Title: "调研", Targets: []string{"notes.md"}, Handoff: "writer"},
+		StepSpec{ID: "s2", Role: "writer", Title: "成文", Targets: []string{"output.md"}, Needs: []string{"s1"}},
+		StepSpec{ID: "s3", Role: "reviewer", Title: "终审", Targets: []string{"output.md"}, Needs: []string{"s2"}},
+	), be, sink, []RoleSpec{
+		{Role: "researcher", Name: "调研", Backend: "handoff-script"},
+		{Role: "writer", Name: "撰写", Backend: "handoff-script"},
+		{Role: "reviewer", Name: "审核", Backend: "handoff-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "带移交的三步"}, RunOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("status = %s err = %v", res.Status, res.Error)
+	}
+	// ① 所有权转移记录持久化。
+	st, err := engine.loadRun(engine.runDir(res.RunID))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(st.Handoffs) != 1 || st.Handoffs[0].FromRole != "researcher" || st.Handoffs[0].ToRole != "writer" {
+		t.Fatalf("Handoffs = %+v", st.Handoffs)
+	}
+	if !strings.Contains(st.Handoffs[0].Output, "MARK_RESEARCHER") {
+		t.Fatalf("移交产出快照缺失：%q", st.Handoffs[0].Output)
+	}
+	if sink.countText("handoff：researcher → writer") != 1 {
+		t.Fatal("缺所有权移交事件")
+	}
+	// ② 目标收过滤历史：writer 的任务书带移交上下文，reviewer 不带。
+	var writerPrompt, reviewerPrompt string
+	for _, p := range be.prompts["02_writer"] {
+		writerPrompt += p
+	}
+	for _, p := range be.prompts["03_reviewer"] {
+		reviewerPrompt += p
+	}
+	if !strings.Contains(writerPrompt, "移交上下文") || !strings.Contains(writerPrompt, "MARK_RESEARCHER") {
+		t.Fatalf("writer 未收到过滤历史：%q", writerPrompt)
+	}
+	if strings.Contains(reviewerPrompt, "移交上下文") {
+		t.Fatal("非目标角色不应收到移交上下文")
+	}
+	// ③ finalize 取链尾输出：交付物 = writer（链尾）产出，而非最后完成的 reviewer。
+	data, err := os.ReadFile(filepath.Join(res.WorkDir, "output.md"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(string(data), "MARK_WRITER") || strings.Contains(string(data), "MARK_REVIEWER") {
+		t.Fatalf("交付物应为链尾 writer 产出：%s", data)
+	}
+}
+
+// handoff 目标角色未知 → 步骤启动前 fail-closed。
+func TestHandoffUnknownRoleFailsClosed(t *testing.T) {
+	be := &handoffScriptBackend{prompts: map[string][]string{}}
+	engine := newWP3Engine(t, mockScriptPlanner(
+		StepSpec{ID: "s1", Role: "researcher", Title: "调研", Handoff: "ghost"},
+	), be, NopSink{}, []RoleSpec{
+		{Role: "researcher", Name: "调研", Backend: "handoff-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "x"}, RunOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunFailed || !strings.Contains(res.Error, "handoff: 未知目标角色 ghost") {
+		t.Fatalf("应 fail-closed：%s %q", res.Status, res.Error)
+	}
+}
+
+// ---- group_chat 驱动 ----
+
+// gcScriptBackend 按目录回放 message.md。
+type gcScriptBackend struct {
+	messages map[string]string
+}
+
+func (b *gcScriptBackend) Name() string { return "gc-script" }
+
+func (b *gcScriptBackend) Execute(_ context.Context, req ExecRequest) (*ExecResult, error) {
+	key := filepath.Base(filepath.Clean(req.WorkDir))
+	msg := b.messages[key]
+	if msg == "" {
+		msg = "发言：" + key
+	}
+	return writeOne(req.WorkDir, "message.md", msg), nil
+}
+
+func TestTopologyConformance_groupChatRotateBudget(t *testing.T) {
+	be := &gcScriptBackend{messages: map[string]string{
+		"turn_01_researcher": "第一句",
+		"turn_02_writer":     "第二句",
+		"turn_03_researcher": "第三句",
+	}}
+	sink := &collectSink{}
+	engine := newWP3Engine(t, mockScriptPlanner(
+		StepSpec{ID: "p1", Role: "researcher", Title: "参与者甲"},
+		StepSpec{ID: "p2", Role: "writer", Title: "参与者乙"},
+	), be, sink, []RoleSpec{
+		{Role: "researcher", Name: "甲", Backend: "gc-script"},
+		{Role: "writer", Name: "乙", Backend: "gc-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "群聊"},
+		RunOptions{Topology: TopologyGroupChat, GroupChatMaxTurns: 3})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("status = %s err = %v", res.Status, res.Error)
+	}
+	// 预算停机：恰好 3 轮，轮转序 researcher→writer→researcher。
+	if sink.countText("轮次预算 3 用尽") != 1 {
+		t.Fatal("缺预算停机事件")
+	}
+	data, err := os.ReadFile(filepath.Join(res.WorkDir, "output.md"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	out := string(data)
+	for _, want := range []string{"1. researcher：第一句", "2. writer：第二句", "3. researcher：第三句"} {
+		if !strings.Contains(out, want) {
+			t.Fatalf("转录缺 %q：%s", want, out)
+		}
+	}
+	if strings.Contains(out, "4. ") {
+		t.Fatalf("超出预算仍在发言：%s", out)
+	}
+	// 名册步骤不执行，标记 skipped（非降级原因）。
+	st, _ := engine.loadRun(engine.runDir(res.RunID))
+	for _, s := range st.Plan.Workflow.Steps {
+		if s.ID == "p1" || s.ID == "p2" {
+			if s.Status != "skipped" || s.Error != gcRosterSkipReason {
+				t.Fatalf("名册步骤 %s = %s/%q", s.ID, s.Status, s.Error)
+			}
+		}
+	}
+}
+
+func TestTopologyConformance_groupChatCloseMarker(t *testing.T) {
+	be := &gcScriptBackend{messages: map[string]string{
+		"turn_01_researcher": "我先说",
+		"turn_02_writer":     "同意收口 [close]",
+	}}
+	sink := &collectSink{}
+	engine := newWP3Engine(t, mockScriptPlanner(
+		StepSpec{ID: "p1", Role: "researcher", Title: "甲"},
+		StepSpec{ID: "p2", Role: "writer", Title: "乙"},
+	), be, sink, []RoleSpec{
+		{Role: "researcher", Name: "甲", Backend: "gc-script"},
+		{Role: "writer", Name: "乙", Backend: "gc-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "群聊"},
+		RunOptions{Topology: TopologyGroupChat, GroupChatMaxTurns: 8})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("status = %s", res.Status)
+	}
+	if sink.countText("发出收口标记") != 1 {
+		t.Fatal("缺收口标记事件")
+	}
+	st, _ := engine.loadRun(engine.runDir(res.RunID))
+	if n := countGcSteps(st); n != 2 {
+		t.Fatalf("收口标记后应停在 2 轮，实际 %d", n)
+	}
+}
+
+func TestTopologyConformance_groupChatModerator(t *testing.T) {
+	be := &gcScriptBackend{messages: map[string]string{
+		"turn_01_researcher": `{"next":"writer","reason":"请乙补充"}`,
+		"turn_02_writer":     "补一段分析",
+		"turn_03_researcher": `{"action":"close","reason":"讨论充分"}`,
+	}}
+	sink := &collectSink{}
+	engine := newWP3Engine(t, mockScriptPlanner(
+		StepSpec{ID: "p1", Role: "researcher", Title: "主持人"},
+		StepSpec{ID: "p2", Role: "writer", Title: "乙"},
+	), be, sink, []RoleSpec{
+		{Role: "researcher", Name: "主持", Backend: "gc-script"},
+		{Role: "writer", Name: "乙", Backend: "gc-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "主持人群聊"}, RunOptions{
+		Topology: TopologyGroupChat, GroupChatPolicy: "moderator",
+		GroupChatModerator: "researcher", GroupChatMaxTurns: 8,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("status = %s err = %v", res.Status, res.Error)
+	}
+	if sink.countText("主持人收口") != 1 {
+		t.Fatal("缺主持人收口事件")
+	}
+	data, _ := os.ReadFile(filepath.Join(res.WorkDir, "output.md"))
+	out := string(data)
+	for _, want := range []string{"1. researcher", "2. writer：补一段分析", "3. researcher"} {
+		if !strings.Contains(out, want) {
+			t.Fatalf("转录缺 %q：%s", want, out)
+		}
+	}
+	st, _ := engine.loadRun(engine.runDir(res.RunID))
+	if n := countGcSteps(st); n != 3 {
+		t.Fatalf("主持人模式应 3 轮收口，实际 %d", n)
+	}
+}
+
+// 主持人指名不在名册 → fail-closed。
+func TestGroupChatModeratorUnknownNextFailsClosed(t *testing.T) {
+	be := &gcScriptBackend{messages: map[string]string{
+		"turn_01_researcher": `{"next":"ghost"}`,
+	}}
+	engine := newWP3Engine(t, mockScriptPlanner(
+		StepSpec{ID: "p1", Role: "researcher", Title: "主持人"},
+		StepSpec{ID: "p2", Role: "writer", Title: "乙"},
+	), be, NopSink{}, []RoleSpec{
+		{Role: "researcher", Name: "主持", Backend: "gc-script"},
+		{Role: "writer", Name: "乙", Backend: "gc-script"},
+	})
+	res, err := engine.Run(context.Background(), Goal{Text: "x"}, RunOptions{
+		Topology: TopologyGroupChat, GroupChatPolicy: "moderator", GroupChatModerator: "researcher",
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunFailed || !strings.Contains(res.Error, "不在名册内") {
+		t.Fatalf("应 fail-closed：%s %q", res.Status, res.Error)
+	}
+}
+
+// ---- 夹具 ----
+
+func countGcSteps(st *RunState) int {
+	n := 0
+	for _, s := range st.Plan.Workflow.Steps {
+		if strings.HasPrefix(s.ID, "gc") && s.Status == "completed" {
+			n++
+		}
+	}
+	return n
+}
+
+func newWP3Engine(t *testing.T, planner Planner, be Executor, sink ProgressSink, roles []RoleSpec) *SquadEngine {
+	t.Helper()
+	dir := t.TempDir()
+	reg := NewRoleRegistry()
+	for _, r := range roles {
+		if err := reg.Register(r); err != nil {
+			t.Fatal(err)
+		}
+	}
+	backends := NewBackendResolver()
+	backends.RegisterInstance(be.Name(), be)
+	engine, err := NewEngine(Options{DataDir: dir, Registry: reg, Planner: planner, Backends: backends, Sink: sink})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return engine
+}

squad/wp4_conformance_test.go

@@ -0,0 +1,355 @@
+package squad
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+// wp4_conformance_test.go — Q2 WP4 验收：task_board 拓扑（claim/lease/complete
+// 原语 + 依赖门 + 孤儿租约再武装）与全 12 拓扑 conformance 汇总跑。
+
+// ---- task_board ----
+
+// 菱形依赖 a→(b,c)→d：认领序尊重依赖门，全部 done，标准 finalize 收口。
+func TestTopologyConformance_taskBoard(t *testing.T) {
+	be := &iterBackend{calls: map[string]int{}}
+	sink := &collectSink{}
+	engine := newTopologyEngine(t, mockScriptPlanner(
+		StepSpec{ID: "a", Role: "researcher", Title: "任务a", Targets: []string{"a.md"}},
+		StepSpec{ID: "b", Role: "writer", Title: "任务b", Needs: []string{"a"}, Targets: []string{"b.md"}},
+		StepSpec{ID: "c", Role: "reviewer", Title: "任务c", Needs: []string{"a"}, Targets: []string{"c.md"}},
+		StepSpec{ID: "d", Role: "writer", Title: "任务d", Needs: []string{"b", "c"}, Targets: []string{"output.md"}},
+	), be, sink)
+	res, err := engine.Run(context.Background(), Goal{Text: "任务板"}, RunOptions{Topology: TopologyTaskBoard})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("status = %s err = %v", res.Status, res.Error)
+	}
+	// 认领序尊重依赖门：a 先于 b/c，d 最后（板上按步骤序认领，确定性）。
+	var order []string
+	for _, ev := range sink.snapshot() {
+		if strings.Contains(ev.Text, "认领") {
+			order = append(order, ev.StepID)
+		}
+	}
+	want := []string{"a", "b", "c", "d"}
+	if strings.Join(order, ",") != strings.Join(want, ",") {
+		t.Fatalf("认领序 = %v，期望 %v", order, want)
+	}
+	st, _ := engine.loadRun(engine.runDir(res.RunID))
+	for _, task := range st.Board {
+		if task.Status != "done" {
+			t.Fatalf("任务 %s = %s，期望 done", task.ID, task.Status)
+		}
+	}
+	if sink.countText("task_board：收口（done 4/4）") != 1 {
+		t.Fatal("缺收口事件")
+	}
+}
+
+// 孤儿租约再武装：崩溃（ctx 取消）留下 claimed+过期租约 → Resume 重入
+// 再武装回 open、重新认领（Attempts=2）并跑完。
+func TestTaskBoardOrphanLeaseRearms(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	crashed := false
+	be := &iterBackend{calls: map[string]int{}, content: func(key string, _ int, _ string) []byte {
+		if key == "02_writer" && !crashed {
+			crashed = true
+			cancel() // 模拟进程死亡：runOneStep 在 ctx 检查处退出，步骤回到 pending
+		}
+		return nil
+	}}
+	sink := &collectSink{}
+	engine := newTopologyEngine(t, mockScriptPlanner(
+		StepSpec{ID: "t1", Role: "researcher", Title: "一", Targets: []string{"a.md"}},
+		StepSpec{ID: "t2", Role: "writer", Title: "二", Needs: []string{"t1"}, Targets: []string{"output.md"}},
+	), be, sink)
+	res0, err := engine.Run(ctx, Goal{Text: "任务板"}, RunOptions{Topology: TopologyTaskBoard})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res0.Status != RunCancelled {
+		t.Fatalf("取消后应为 RunCancelled：%s", res0.Status)
+	}
+	// 崩溃现场：t2 claimed、租约未过期；步骤在盘上是 running（setStep 只改
+	// 内存，取消路径的 pending 未落盘）——进程死亡即此形态。测试把租约回拨
+	// 成过期（孤儿）并把步骤置回 pending（模拟重启前的一致化），再走 Resume。
+	st, err := engine.loadRun(engine.runDir(res0.RunID))
+	if err != nil {
+		t.Fatal(err)
+	}
+	found := false
+	for i := range st.Board {
+		if st.Board[i].ID == "t2" {
+			found = true
+			if st.Board[i].Status != "claimed" || st.Board[i].Attempts != 1 {
+				t.Fatalf("崩溃现场 t2 = %+v", st.Board[i])
+			}
+			st.Board[i].LeaseExpires = time.Now().Add(-time.Hour) // 租约过期 = 孤儿
+		}
+	}
+	if !found {
+		t.Fatal("板上无 t2")
+	}
+	for i := range st.Plan.Workflow.Steps {
+		if st.Plan.Workflow.Steps[i].ID == "t2" && st.Plan.Workflow.Steps[i].Status == "running" {
+			st.Plan.Workflow.Steps[i].Status = "pending"
+		}
+	}
+	if err := st.save(); err != nil {
+		t.Fatal(err)
+	}
+	// 重入：孤儿租约再武装 → 重新认领 → 跑完收口。
+	res, err := engine.Resume(context.Background(), st.Meta.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunCompleted {
+		t.Fatalf("恢复后应完成：%s %v", res.Status, res.Error)
+	}
+	if sink.countText("孤儿租约再武装 t2") != 1 {
+		t.Fatal("缺孤儿租约再武装事件")
+	}
+	st2, _ := engine.loadRun(engine.runDir(res.RunID))
+	for _, task := range st2.Board {
+		if task.ID == "t2" && task.Attempts != 2 {
+			t.Fatalf("再武装后 Attempts = %d，期望 2", task.Attempts)
+		}
+	}
+}
+
+// 依赖门级联：非关键任务失败 → 下游 open 任务级联 skipped → 降级收口。
+func TestTaskBoardDependencyGateCascade(t *testing.T) {
+	be := &iterBackend{calls: map[string]int{}, content: func(key string, _ int, _ string) []byte {
+		return nil
+	}}
+	failBe := &failOnceBackend{inner: be, failKey: "02_writer"}
+	crit := false
+	sink := &collectSink{}
+	engine := newTopologyEngine(t, mockScriptPlanner(
+		StepSpec{ID: "t0", Role: "researcher", Title: "零", Targets: []string{"output.md"}},
+		StepSpec{ID: "t1", Role: "writer", Title: "一", Needs: []string{"t0"}, Targets: []string{"b.md"}, Critical: &crit},
+		StepSpec{ID: "t2", Role: "reviewer", Title: "二", Needs: []string{"t1"}, Targets: []string{"c.md"}},
+	), failBe, sink)
+	res, err := engine.Run(context.Background(), Goal{Text: "任务板"}, RunOptions{Topology: TopologyTaskBoard})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != RunDegraded {
+		t.Fatalf("非关键失败+级联跳过应降级收口：%s %v", res.Status, res.Error)
+	}
+	st, _ := engine.loadRun(engine.runDir(res.RunID))
+	byID := map[string]BoardTask{}
+	for _, task := range st.Board {
+		byID[task.ID] = task
+	}
+	if byID["t0"].Status != "done" || byID["t1"].Status != "failed" || byID["t2"].Status != "skipped" {
+		t.Fatalf("板状态 = %+v", byID)
+	}
+	for _, s := range st.Plan.Workflow.Steps {
+		if s.ID == "t2" && (s.Status != "skipped" || s.Error != boardSkipReason) {
+			t.Fatalf("t2 = %s %q", s.Status, s.Error)
+		}
+	}
+}
+
+// failOnceBackend 对指定目录恒定失败（非瞬态），其余委托 inner。
+type failOnceBackend struct {
+	inner   Executor
+	failKey string
+}
+
+func (b *failOnceBackend) Name() string { return b.inner.Name() }
+
+func (b *failOnceBackend) Execute(ctx context.Context, req ExecRequest) (*ExecResult, error) {
+	key := filepath.Base(filepath.Clean(req.WorkDir))
+	if key == b.failKey {
+		return &ExecResult{Success: false, ErrorReason: "fatal: 拒绝执行"}, nil
+	}
+	return b.inner.Execute(ctx, req)
+}
+
+// ---- 12/12 汇总 ----
+
+// TestTopologyConformance_allTwelve 全 12 内置拓扑汇总跑：每个拓扑名一次
+// 脚本化最小运行（零模型零网络）。graph/mode/driver 十种断言完成收口；
+// handoff/mailbox 两个 primitive 断言 fail-closed 拒绝单跑（其原语能力分别
+// 由 TestTopologyConformance_handoff 与 WP2 mailbox 测试钉住）。
+func TestTopologyConformance_allTwelve(t *testing.T) {
+	specs := BuiltinTopologies()
+	if len(specs) != 12 {
+		t.Fatalf("内置拓扑 = %d，期望 12", len(specs))
+	}
+	for _, spec := range specs {
+		spec := spec
+		t.Run(spec.Name, func(t *testing.T) {
+			switch spec.Name {
+			case TopologySequential:
+				runAgg(t, spec.Name, mockScriptPlanner(
+					StepSpec{ID: "s1", Role: "researcher", Title: "一", Targets: []string{"output.md"}},
+				), &iterBackend{calls: map[string]int{}}, RunOptions{}, RunCompleted)
+			case TopologyParallel:
+				runAgg(t, spec.Name, mockScriptPlanner(
+					StepSpec{ID: "s1", Role: "researcher", Title: "甲", Parallel: true, Targets: []string{"a.md"}},
+					StepSpec{ID: "s2", Role: "writer", Title: "乙", Parallel: true, Targets: []string{"output.md"}},
+				), &iterBackend{calls: map[string]int{}}, RunOptions{}, RunCompleted)
+			case TopologyLoop:
+				runAgg(t, spec.Name, mockScriptPlanner(
+					StepSpec{ID: "s1", Role: "researcher", Title: "循环体", Targets: []string{"output.md", "fields.json"},
+						Loop: &LoopSpec{MaxIterations: 2, UntilField: "done", UntilEquals: "yes"}},
+				), &iterBackend{calls: map[string]int{}, content: func(_ string, _ int, target string) []byte {
+					if target == "fields.json" {
+						return fieldsJSON(map[string]string{"done": "no"})
+					}
+					return nil
+				}}, RunOptions{}, RunCompleted)
+			case TopologyRouter:
+				runAgg(t, spec.Name, mockScriptPlanner(routerSteps()...),
+					&iterBackend{calls: map[string]int{}, content: func(_ string, _ int, target string) []byte {
+						if target == "fields.json" {
+							return fieldsJSON(map[string]string{"route": "fast"})
+						}
+						return nil
+					}}, RunOptions{}, RunCompleted)
+			case TopologyEvaluatorOptimizer:
+				runAgg(t, spec.Name, mockScriptPlanner(
+					StepSpec{ID: "draft", Role: "writer", Title: "起草", Targets: []string{"output.md"}},
+					StepSpec{ID: "eval", Role: "reviewer", Title: "评审", Targets: []string{"verdict.md", "fields.json"},
+						Loop: &LoopSpec{MaxIterations: 4, UntilField: "verdict", UntilEquals: "pass", Body: []string{"draft"}}},
+				), &iterBackend{calls: map[string]int{}, content: func(_ string, iter int, target string) []byte {
+					if target == "fields.json" {
+						if iter >= 3 {
+							return fieldsJSON(map[string]string{"verdict": "pass"})
+						}
+						return fieldsJSON(map[string]string{"verdict": "fail"})
+					}
+					return nil
+				}}, RunOptions{}, RunCompleted)
+			case TopologyLongRunning:
+				runAgg(t, spec.Name, mockScriptPlanner(
+					StepSpec{ID: "s1", Role: "researcher", Title: "一", Targets: []string{"output.md"}},
+				), &iterBackend{calls: map[string]int{}},
+					RunOptions{Deadline: time.Now().Add(5 * time.Second)}, RunCompleted)
+			case TopologyLeader:
+				b := &leaderScriptBackend{
+					decisions: []string{delegateJSON("writer", "撰写简报"), closeJSON},
+					script:    map[string]map[string]string{"01_writer": {"output.md": goodReport}},
+				}
+				engine := newLeaderEngine(t, b)
+				res, err := engine.Run(context.Background(), Goal{Text: "汇总"}, RunOptions{Topology: TopologyLeader})
+				if err != nil {
+					t.Fatal(err)
+				}
+				if res.Status != RunCompleted {
+					t.Fatalf("status = %s err = %v", res.Status, res.Error)
+				}
+			case TopologyReview:
+				planner := mockScriptPlanner(
+					StepSpec{ID: "f1", Role: "researcher", Title: "评审", Targets: []string{"findings.json"}},
+				)
+				planner.Agents = []RoleSpec{
+					{Role: "researcher", Name: "评审", Backend: "agg-review"},
+					{Role: "verifier", Name: "核实", Backend: "agg-review"},
+				}
+				engine := newAggEngine(t, planner, &aggReviewBackend{}, []RoleSpec{
+					{Role: "researcher", Name: "评审", Backend: "agg-review"},
+					{Role: "verifier", Name: "核实", Backend: "agg-review"},
+				})
+				res, err := engine.Run(context.Background(), Goal{Text: "评审"},
+					RunOptions{Topology: TopologyReview, ReviewTarget: "材料"})
+				if err != nil {
+					t.Fatal(err)
+				}
+				if res.Status != RunCompleted {
+					t.Fatalf("status = %s err = %v", res.Status, res.Error)
+				}
+				data, _ := os.ReadFile(filepath.Join(res.WorkDir, "output.md"))
+				if !strings.Contains(string(data), "已丢弃 0 条未验证") || !strings.Contains(string(data), "样例问题") {
+					t.Fatalf("报告 = %s", data)
+				}
+			case TopologyGroupChat:
+				engine := newAggEngine(t, mockScriptPlanner(
+					StepSpec{ID: "p1", Role: "researcher", Title: "甲"},
+					StepSpec{ID: "p2", Role: "writer", Title: "乙"},
+				), &gcScriptBackend{}, []RoleSpec{
+					{Role: "researcher", Name: "甲", Backend: "gc-script"},
+					{Role: "writer", Name: "乙", Backend: "gc-script"},
+				})
+				res, err := engine.Run(context.Background(), Goal{Text: "群聊"},
+					RunOptions{Topology: TopologyGroupChat, GroupChatMaxTurns: 2})
+				if err != nil {
+					t.Fatal(err)
+				}
+				if res.Status != RunCompleted {
+					t.Fatalf("status = %s err = %v", res.Status, res.Error)
+				}
+			case TopologyTaskBoard:
+				runAgg(t, spec.Name, mockScriptPlanner(
+					StepSpec{ID: "t1", Role: "researcher", Title: "一", Targets: []string{"a.md"}},
+					StepSpec{ID: "t2", Role: "writer", Title: "二", Needs: []string{"t1"}, Targets: []string{"output.md"}},
+				), &iterBackend{calls: map[string]int{}}, RunOptions{}, RunCompleted)
+			case TopologyHandoff, TopologyMailbox:
+				// primitive：不可单独作为运行拓扑（fail-closed）；原语能力由
+				// 专项 conformance 钉住（handoff/mailbox 测试）。
+				runAgg(t, spec.Name, mockScriptPlanner(
+					StepSpec{ID: "s1", Role: "researcher", Title: "一", Targets: []string{"output.md"}},
+				), &iterBackend{calls: map[string]int{}}, RunOptions{}, RunFailed)
+			default:
+				t.Fatalf("未覆盖的拓扑 %q", spec.Name)
+			}
+		})
+	}
+}
+
+// runAgg 汇总跑的最小引擎：graph 类拓扑共用 iter 三角色装配。
+func runAgg(t *testing.T, topo string, planner Planner, be Executor, opts RunOptions, want RunStatus) {
+	t.Helper()
+	opts.Topology = topo
+	engine := newTopologyEngine(t, planner, be, nil)
+	res, err := engine.Run(context.Background(), Goal{Text: "汇总跑 " + topo}, opts)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if res.Status != want {
+		t.Fatalf("status = %s err = %q，期望 %s", res.Status, res.Error, want)
+	}
+}
+
+// aggReviewBackend 汇总跑用的最小 review 后端：finder 出一条发现，verify 判 PASS。
+type aggReviewBackend struct{}
+
+func (b *aggReviewBackend) Name() string { return "agg-review" }
+
+func (b *aggReviewBackend) Execute(_ context.Context, req ExecRequest) (*ExecResult, error) {
+	key := filepath.Base(filepath.Clean(req.WorkDir))
+	if strings.HasPrefix(key, "verify_") {
+		return writeOne(req.WorkDir, "verdict.md", "核对成立。\nVERDICT: PASS"), nil
+	}
+	return writeOne(req.WorkDir, "findings.json",
+		`[{"location":"第1段","severity":"high","issue":"样例问题","evidence":"样例证据"}]`), nil
+}
+
+// newAggEngine 自定义角色表的汇总引擎（backend 实例名 = be.Name()）。
+func newAggEngine(t *testing.T, planner Planner, be Executor, roles []RoleSpec) *SquadEngine {
+	t.Helper()
+	dir := t.TempDir()
+	reg := NewRoleRegistry()
+	for _, r := range roles {
+		if err := reg.Register(r); err != nil {
+			t.Fatal(err)
+		}
+	}
+	backends := NewBackendResolver()
+	backends.RegisterInstance(be.Name(), be)
+	engine, err := NewEngine(Options{DataDir: dir, Registry: reg, Planner: planner, Backends: backends, Sink: NopSink{}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return engine
+}