Add the generative-ui plugin, capability gating, and surface projection

Why: Generative UI U3 - the agent needs a real submission path and the
next turn needs to see prior pages: a built-in in-process plugin
registers generative-ui.present (exposeAsTool) carrying the catalog
(prompt=validation single source) with a schema-repair strategy
measured against real MiniMax-M3 deviations; the command bus gains an
owner-scoped tool gate so a disabled plugin stops injecting its tool
(execution guard remains in surfacesvc); ctxasm projects saved surfaces
back into context so the model can revise existing structure; doc-refs
are authorized against the owner's real artifacts.

Evidence: unit suites green (genui guards/epoch/doc-ref, gate fail-closed,
projection content); full go test ./... green; cmdbus/ctxasm also green
under AGENT_PG_TEST_DSN; real-model closed loop (env-gated
TestRealModelSurfaceLoop) passes: task->spec->save->projection->revise
with revision 1->2 and structure change, CNY 0.08 total.

Impact: New internal/genui package; additive cmdbus/ctxasm/runmgr/
runtime hooks; no storage or contract changes (U2 layer untouched).

Refs: Documents proposal r2 U3; Core PR #25/#26; Backend #143; Dev task
feature/generative-ui-u3

internal/app/app.go

@@ -34,6 +34,7 @@ import (
 	"agent-system-backend/internal/cardsvc"
 	"agent-system-backend/internal/cmdbus"
 	"agent-system-backend/internal/config"
+	"agent-system-backend/internal/genui"
 	"agent-system-backend/internal/hostapi"
 	"agent-system-backend/internal/intentgate"
 	"agent-system-backend/internal/intentsem"
@@ -493,6 +494,16 @@ func Run(opt Options) error {
 
 	// 命令总线（提案 T3/D27/D30）：四入口同源分发 + 审计 + 危险内联确认卡。
 	bus := cmdbus.New(st, cardSvc, func() time.Time { return time.Now().UTC() })
+	// U3：generative-ui 工具注入闸——activation 台账关闭时命令不投影给该 owner
+	// 的模型（禁用即不注入能力；执行端守卫仍在 surfacesvc）。
+	bus.SetToolGate(func(owner, commandID string) bool {
+		if !strings.HasPrefix(commandID, genui.PluginID+".") {
+			return true
+		}
+		row, err := surfaceSvc.Activation(context.Background(), owner, genui.PluginID)
+		return err == nil && row.Enabled
+	})
+
 	bus.SetPendingStore(st)
 	pluginHost.OnCommands = bus.RegisterPluginCommands
 	// hostcaps：hostapi 闭包与进程内插件句柄共用的 owner 作用域能力（EXT-1 批注 1）。
@@ -824,7 +835,11 @@ func splitKeyPool(s string) []string {
 type busAdapter struct{ bus *cmdbus.Bus }
 
 func (a busAdapter) CommandTools() []runmgr.CommandTool {
-	src := a.bus.CommandTools()
+	return a.CommandToolsFor("")
+}
+
+func (a busAdapter) CommandToolsFor(owner string) []runmgr.CommandTool {
+	src := a.bus.CommandToolsFor(owner)
 	out := make([]runmgr.CommandTool, len(src))
 	for i, ct := range src {
 		out[i] = runmgr.CommandTool{ID: ct.ID, Description: ct.Description, Params: ct.Params, Risk: ct.Risk}

internal/cmdbus/cmdbus.go

@@ -45,12 +45,28 @@ type CommandTool struct {
 }
 
 // CommandTools 全部带 ExposeAsTool 的已启用命令（EXT-14 工具投影源）。
+// ToolGate 是 owner 级工具注入闸（U3：禁用即不注入能力）：返回 false 时该命令
+// 不投影给该 owner 的模型。组合根按需装配（如 generative-ui 按 activation 台账）。
+type ToolGate func(owner, commandID string) bool
+
+// SetToolGate 装配 owner 级注入闸（组合根；启动期一次）。
+func (b *Bus) SetToolGate(g ToolGate) { b.toolGate = g }
+
 func (b *Bus) CommandTools() []CommandTool {
+	return b.CommandToolsFor("")
+}
+
+// CommandToolsFor 按 owner 过滤工具投影（gate 为 nil 时不过滤；owner 为空时
+// gated 命令一律不投影——fail-closed）。
+func (b *Bus) CommandToolsFor(owner string) []CommandTool {
 	out := []CommandTool{}
 	for _, r := range b.reg.List() {
 		if !r.Enabled || r.Spec.ExposeAsTool == nil {
 			continue
 		}
+		if b.toolGate != nil && !b.toolGate(owner, r.Spec.ID) {
+			continue
+		}
 		risk := r.Spec.ExposeAsTool.Risk
 		if risk == "" {
 			risk = "low"
@@ -101,6 +117,7 @@ type Bus struct {
 	pending      map[string]pending
 	pendingStore PendingStore
 	intents      *IntentStore // G2-2：意图声明表（自然语言路由）
+	toolGate     ToolGate     // U3：owner 级工具注入闸（nil = 不过滤）
 }
 
 // PendingStore 把危险命令的确认挂起态落盘。进程内 map 仍是热路径；重启后从存储取回。

internal/cmdbus/command_tools_test.go

@@ -6,6 +6,7 @@ package cmdbus
 import (
 	"context"
 	"encoding/json"
+	"strings"
 	"testing"
 	"time"
 
@@ -72,3 +73,30 @@ func TestCommandToolDispatchEnvelope(t *testing.T) {
 type nopAudit struct{}
 
 func (nopAudit) AppendAudit(owner string, env agentcommand.AuditEnvelope) error { return nil }
+
+// U3：owner 级注入闸——gate 拒绝的命令不投影（禁用即不注入能力）；fail-closed
+// （owner 为空且 gate 判否时不投影）。
+func TestCommandToolsForGate(t *testing.T) {
+	bus := New(nil, nil, func() time.Time { return time.Now().UTC() })
+	if err := bus.RegisterPluginCommands([]json.RawMessage{
+		[]byte(`{"id":"generative-ui.present","title":"生成页面","description":"d","paramsSchema":{"type":"object"},"exposeAsTool":{"risk":"low"}}`),
+		[]byte(`{"id":"other.echo","title":"回声","description":"e","paramsSchema":{"type":"object"},"exposeAsTool":{"risk":"low"}}`),
+	}); err != nil {
+		t.Fatal(err)
+	}
+	bus.SetToolGate(func(owner, id string) bool {
+		return !strings.HasPrefix(id, "generative-ui.")
+	})
+	on := bus.CommandToolsFor("alice")
+	for _, ct := range on {
+		if strings.HasPrefix(ct.ID, "generative-ui.") {
+			t.Fatalf("gated command leaked for enabled owner: %+v", ct)
+		}
+	}
+	if len(on) != 1 {
+		t.Fatalf("expected only other.echo, got %+v", on)
+	}
+	if n := len(bus.CommandToolsFor("")); n != 1 {
+		t.Fatalf("empty owner must be fail-closed on gated commands, got %d", n)
+	}
+}

internal/ctxasm/ctxasm.go

@@ -41,6 +41,9 @@ type AssembleOptions struct {
 	// ThinkReplay 为真时，历史 assistant 消息的思考部件以 <think> 块原样回传
 	//（交错思考模型如 MiniMax 的官方要求：丢弃思考内容会降低后续轮性能）。
 	ThinkReplay bool
+	// Surfaces 是当前会话最近保存的生成页面（U3/R6）：以语义投影并入上下文，
+	// 使下一轮模型能解释并修改已有结构（修改走 generative-ui.present 重提）。
+	Surfaces []core.SurfaceSnapshot
 }
 
 // AssembleInput 组装模型输入消息。sys 为提示词库组装出的 system 段（可为多段；
@@ -58,6 +61,17 @@ func AssembleInput(prof core.AgentProfile, eff core.EffectiveSettings, history [
 		msgs = append(msgs, agentllm.Message{Role: agentllm.RoleSystem, Content: prof.SystemPrompt})
 		rep.Items = append(rep.Items, "system(画像自定义段)")
 	}
+	if len(opts.Surfaces) > 0 {
+		var b strings.Builder
+		b.WriteString("[本会话已保存的生成页面（结构摘要；正文以预览区为准）]\n")
+		for _, snap := range opts.Surfaces {
+			b.WriteString(projectSurface(snap))
+			b.WriteString("\n")
+		}
+		b.WriteString("用户要求调整页面时，按结构摘要理解现状并用 generative-ui.present 提交修订（带 surfaceId 与 baseRevision）。")
+		msgs = append(msgs, agentllm.Message{Role: agentllm.RoleSystem, Content: b.String()})
+		rep.Items = append(rep.Items, fmt.Sprintf("surface(%d)", len(opts.Surfaces)))
+	}
 
 	maxHist := prof.Context.MaxHistoryMessages
 	if maxHist <= 0 {
@@ -499,3 +513,42 @@ func InjectMemory(sys []agentllm.Message, entries []core.MemoryEntry) []agentllm
 	out = append(out, agentllm.Message{Role: agentllm.RoleSystem, Content: b.String()})
 	return out
 }
+
+// projectSurface 是 ctxasm 侧的结构摘要投影（与 surfacesvc.ProjectSurface 同义；
+// 独立实现避免 ctxasm→surfacesvc 依赖边）。
+func projectSurface(snap core.SurfaceSnapshot) string {
+	var b strings.Builder
+	fmt.Fprintf(&b, "- 页面 %s（修订 %d）%q", string(snap.Identity.SurfaceID), snap.Revision, snap.Spec.Title)
+	if snap.SemanticText != "" {
+		fmt.Fprintf(&b, "：%s", snap.SemanticText)
+	}
+	b.WriteString("\n  结构：")
+	var walk func(n core.UINode)
+	first := true
+	walk = func(n core.UINode) {
+		label := string(n.Type)
+		if n.Title != "" {
+			label += "(\"" + n.Title + "\")"
+		}
+		if n.ID != "" {
+			label += "#" + n.ID
+		}
+		if len(n.Source) > 0 {
+			label += "[" + strings.Join(n.Source, ",") + "]"
+		}
+		if first {
+			b.WriteString(label)
+			first = false
+		} else {
+			b.WriteString(" > " + label)
+		}
+		for _, c := range n.Children {
+			walk(c)
+		}
+	}
+	for _, n := range snap.Spec.Nodes {
+		walk(n)
+	}
+	b.WriteString("\n  修订此页：present 带 surfaceId=" + string(snap.Identity.SurfaceID) + " 与 baseRevision=" + fmt.Sprint(snap.Revision) + "。")
+	return b.String()
+}

internal/ctxasm/surface_proj_test.go

@@ -0,0 +1,52 @@
+package ctxasm
+
+// U3/R6：已保存页面的语义投影并入上下文——下一轮模型能看到结构、来源与修订
+// 入口（present + baseRevision），可据此解释并修改已有 table/compare/tabs。
+
+import (
+	"strings"
+	"testing"
+
+	agentllm "agent-native/runtime/llm"
+	core "agent-system-core"
+)
+
+func surfaceSnap() core.SurfaceSnapshot {
+	return core.SurfaceSnapshot{
+		Identity: core.SurfaceIdentity{SurfaceID: "surf_x", Owner: "alice", PluginID: "generative-ui", ConversationID: "c1"},
+		Revision: 2,
+		Spec: core.SurfaceSpec{Title: "选型对比", Nodes: []core.UINode{
+			{Type: core.UISection, ID: "n1", Title: "概览", Children: []core.UINode{
+				{Type: core.UIMarkdown, ID: "n1a", Source: []string{"doc:a"}, Markdown: "结论"},
+			}},
+			{Type: core.UITable, ID: "n2", Source: []string{"doc:a", "doc:b"}},
+		}},
+		SemanticText: "三工具对比页",
+	}
+}
+
+func TestSurfaceProjectionInContext(t *testing.T) {
+	msgs, rep := AssembleInput(core.AgentProfile{}, nil, nil,
+		core.Message{Role: core.RoleUser, Parts: []core.Part{{Type: core.PartText, Text: "改一下"}}},
+		nil, nil, nil, nil, nil, nil, AssembleOptions{Surfaces: []core.SurfaceSnapshot{surfaceSnap()}})
+	joined := make([]string, len(msgs))
+	for i, m := range msgs {
+		joined[i] = m.Content
+	}
+	all := strings.Join(joined, "\n---\n")
+	for _, need := range []string{"surf_x", "修订 2", "选型对比", "section(\"概览\")#n1", "markdown#n1a[doc:a]", "table#n2", "baseRevision=2"} {
+		if !strings.Contains(all, need) {
+			t.Fatalf("projection missing %q in assembled context:\n%s", need, all)
+		}
+	}
+	found := false
+	for _, it := range rep.Items {
+		if strings.HasPrefix(it, "surface(") {
+			found = true
+		}
+	}
+	if !found {
+		t.Fatalf("report should count surface injection: %v", rep.Items)
+	}
+	_ = agentllm.RoleSystem
+}

internal/genui/genui.go

@@ -0,0 +1,282 @@
+// Package genui 是 Generative UI 的内置进程内插件（提案 U3）：
+// 当前 Agent 经 exposeAsTool 的 generative-ui.present 命令提交声明式页面，
+// 宿主（EXT-17 SurfaceHost）校验并原子发布；目录=提示=校验三同源。
+// 不接管对话循环、模型凭据或任务执行权（KTD2）；不另造 Agent runtime。
+package genui
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"agent-system-backend/pkg/extension"
+	core "agent-system-core"
+)
+
+// PluginID 是插件身份（activation 台账与命令前缀共用）。
+const PluginID = "generative-ui"
+
+// CommandPresent 是唯一提交命令 id（revise 即带 surfaceId+baseRevision 的再次 present）。
+const CommandPresent = PluginID + ".present"
+
+// Catalog 是组件目录与纪律（U1 试验 CATALOG_PROMPT 的 Go 权威版；工具描述携带，
+// 模型与校验器看到同一份规则）。修改需同步 core.ValidateSurfaceSpec 与目录版本。
+const Catalog = `可用节点类型（16 种；字段必须严格匹配，禁止目录外类型/字段）：
+section{title?,children?}；list{items:string[]}；kv{kv:[[k,v]]}；
+form{fields:[{key,label,type:text|textarea|number|boolean|select,options?(select必填),required?,placeholder?,help?,default?}]}；
+markdown{markdown}；doc-ref{docId}(须为会话内存在的工件ID)；
+actions{actions:[{id,label,style?:primary|default|danger}]}(不带command)；
+chart-lite{chart:{kind:bar|line,labels:[],series:[]等长}}；avatar{avatar:{name,sub?,tone?:ok|warn|danger|info,stack?}}；
+progress{progress:{label?,value:0~1}}；compare{compare:{left:{title?,tone?,nodes?},right:{同left}}}；
+tree{tree:{nodes:[{id,label,tone?,badge?,count?,children?}]}}；
+table{table:{columns:[{key,label}],rows:[{id?,cells:[[key,值]与columns等长同序}]}}；
+steps{steps:{current:0起,steps:[{label,status?:pending|active|done|failed,tone?}]}}；
+tabs{tabs:{tabs:[{id,label,nodes?}],active?}}；timeline{timeline:{items:[{title,time?,tone?,markdown?,ref?}]}}。
+规则：每节点可带 id（整页唯一稳定）与 source[]（支撑事实的来源标识）；事实性内容标注来源，
+分析/建议只放 markdown 且不加 source；≤200 节点、≤8 层、≤256KiB；未知类型/字段与未知
+doc-ref 会被拒绝并返回字段级错误（可修正后重提一次）。结构服务目标：比较→compare/table；
+风险→按严重度组织；顺序→steps/timeline；收集输入→form。
+最小完整示例（spec 参数的形状；title 与 nodes 在顶层，source 挂在节点上）：
+{"title":"示例页","nodes":[
+ {"type":"section","id":"n1","title":"结论","children":[
+   {"type":"markdown","id":"n1a","source":["doc:m1"],"markdown":"结论先行。"}]},
+ {"type":"table","id":"n2","table":{"columns":[{"key":"k","label":"维度"},{"key":"v","label":"值"}],
+   "rows":[{"id":"r1","cells":[["k","报价"],["v","¥8/人/天"]]}]}},
+ {"type":"steps","id":"n3","steps":{"current":0,"steps":[{"label":"评审","status":"pending"}]}}]}`
+
+func init() {
+	extension.RegisterCompiled(extension.InProc{ID: PluginID, Register: register})
+}
+
+func register(reg extension.Registry) error {
+	spec := json.RawMessage(fmt.Sprintf(`{
+		"id": %q,
+		"title": "生成页面",
+		"description": %q,
+		"paramsSchema": {
+			"type": "object",
+			"properties": {
+				"spec": {"type": "object", "description": "页面规格：顶层恰为 {title: string, nodes: [节点数组]}",
+					"properties": {"title": {"type": "string"}, "nodes": {"type": "array", "items": {"type": "object"}}},
+					"required": ["title", "nodes"]},
+				"surfaceId": {"type": "string", "description": "修订已有页面时传入"},
+				"baseRevision": {"type": "integer", "description": "修订基于的当前修订号"},
+				"summary": {"type": "string", "description": "一句话语义摘要（回放与索引用）"}
+			},
+			"required": ["spec"]
+		},
+		"exposeAsTool": {"risk": "low"}
+	}`, CommandPresent, "提交一页声明式页面（由宿主校验、保存并在预览区渲染）。"+Catalog))
+	return reg.AddCommandHandler(spec, present)
+}
+
+// present 是命令处理器：经 owner 作用域 Host 的 SurfaceHost 能力提交页面。
+// 能力缺失（宿主未装配）与未启用明确报错；doc-ref 经 owner 作用域工件解析做
+// 真实授权（伪造引用拒绝）；校验失败返回字段级清单供模型修复重提（至多一次）。
+func present(ctx context.Context, h extension.Host, req extension.Request) (any, error) {
+	sh, ok := h.(extension.SurfaceHost)
+	if !ok {
+		return nil, fmt.Errorf("generative-ui: surface capability not available in this host")
+	}
+	enabled, epoch, err := sh.SurfaceActivation(ctx)
+	if err != nil {
+		return nil, err
+	}
+	if !enabled {
+		return nil, fmt.Errorf("generative-ui: 插件未启用（owner 未开启 Surface 能力），本次提交被拒绝")
+	}
+	raw, _ := json.Marshal(normalizeSpecParam(req.Params["spec"]))
+	surfaceID, _ := req.Params["surfaceId"].(string)
+	base := 0
+	if v, ok := req.Params["baseRevision"].(float64); ok {
+		base = int(v)
+	}
+	summary, _ := req.Params["summary"].(string)
+
+	// doc-ref 真实授权：spec 里的 docId 必须是当前 owner 可解析的工件（伪造即拒）。
+	if errs := authorizeDocRefs(raw, h); len(errs) > 0 {
+		return toolError("invalid spec", errs), nil
+	}
+	snap, err := sh.SurfaceSave(ctx, extension.SurfaceSaveRequest{
+		SurfaceID:      core.ID(surfaceID),
+		ConversationID: core.ID(req.ConversationID),
+		BaseRevision:   base,
+		ObservedEpoch:  epoch,
+		SemanticText:   summary,
+		Spec:           raw,
+	})
+	if err != nil {
+		if strings.HasPrefix(err.Error(), "surface: invalid spec:") {
+			details := strings.TrimSpace(strings.TrimPrefix(err.Error(), "surface: invalid spec:"))
+			var list []string
+			for _, d := range strings.Split(details, ";") {
+				if t := strings.TrimSpace(d); t != "" {
+					list = append(list, t)
+				}
+			}
+			return toolError("invalid spec", list), nil
+		}
+		return nil, err
+	}
+	return map[string]any{
+		"ok":        true,
+		"surfaceId": string(snap.Identity.SurfaceID),
+		"revision":  snap.Revision,
+		"epoch":     snap.ActivationEpoch,
+		"summary":   snap.SemanticText,
+		"note":      "页面已保存；用户在预览区查看。修订时带 surfaceId 与 baseRevision 重提。",
+	}, nil
+}
+
+// toolError 是返回给模型的字段级错误（工具结果错误，非分发错误）。
+type toolErrorBody struct {
+	OK      bool     `json:"ok"`
+	Error   string   `json:"error"`
+	Details []string `json:"details,omitempty"`
+	Note    string   `json:"note"`
+}
+
+func toolError(msg string, details []string) toolErrorBody {
+	return toolErrorBody{OK: false, Error: msg, Details: details,
+		Note: "按错误修正 spec 后可重提一次；再次失败请改用文本回答。"}
+}
+
+// normalizeSpecParam 是插件的 schema 修复策略（r1 KTD1；U3 回放实测的模型偏差
+// 逐条落地）：单键包装（{"page":…}）解包；顶层 children→nodes；kv/cells 的
+// 对象形式（{"k":…,"v":…}/{"key":…,"value":…}）改写为二元组数组。只做结构
+// 改写，不改内容语义；修复后仍过 core 校验器。
+func normalizeSpecParam(v any) any {
+	if arr, ok := v.([]any); ok {
+		return map[string]any{"title": "", "nodes": arr}
+	}
+	m, ok := v.(map[string]any)
+	if !ok {
+		return v
+	}
+	if len(m) == 1 {
+		if inner, ok := m["page"].(map[string]any); ok {
+			m = inner
+		}
+	}
+	if _, ok := m["nodes"]; !ok {
+		if ch, ok := m["children"].([]any); ok {
+			m["nodes"] = ch
+			delete(m, "children")
+		}
+	}
+	// 页级 source（模型的常见引用写法）：分发给未自带 source 的节点——保留引用
+	// 信息，不发明内容；节点自带 source 者不受影响。
+	if top, ok := m["source"].([]any); ok {
+		delete(m, "source")
+		if nodes, ok := m["nodes"].([]any); ok {
+			for _, n := range nodes {
+				if nm, ok := n.(map[string]any); ok {
+					if _, has := nm["source"]; !has {
+						cp := make([]any, len(top))
+						copy(cp, top)
+						nm["source"] = cp
+					}
+				}
+			}
+		}
+	}
+	repairPairs(m)
+	return m
+}
+
+// repairPairs 递归把 "kv"/"cells" 下的对象项改写为二元组。
+func repairPairs(node any) {
+	m, ok := node.(map[string]any)
+	if !ok {
+		return
+	}
+	for key, val := range m {
+		if (key == "kv" || key == "cells") && val != nil {
+			if arr, ok := val.([]any); ok {
+				fixed := make([]any, 0, len(arr))
+				changed := false
+				for _, item := range arr {
+					if p, ok := pairFromObject(item); ok {
+						fixed = append(fixed, p)
+						changed = true
+					} else {
+						fixed = append(fixed, item)
+					}
+				}
+				if changed {
+					m[key] = fixed
+				}
+			}
+		}
+		repairPairs(val)
+	}
+}
+
+// pairFromObject 从 {"k","v"}/{"key","value"}/{"name","value"} 对象提取二元组。
+func pairFromObject(item any) ([2]any, bool) {
+	obj, ok := item.(map[string]any)
+	if !ok {
+		return [2]any{}, false
+	}
+	var k, v any
+	for kk, vv := range obj {
+		switch kk {
+		case "k", "key", "name":
+			k = vv
+		case "v", "value":
+			v = vv
+		default:
+			return [2]any{}, false
+		}
+	}
+	if k == nil || v == nil {
+		return [2]any{}, false
+	}
+	ks, ok1 := k.(string)
+	vs, ok2 := v.(string)
+	if !ok1 || !ok2 {
+		return [2]any{}, false
+	}
+	return [2]any{ks, vs}, true
+}
+
+// authorizeDocRefs 收集 spec 中的 doc-ref docId 并经 Host 工件面做 owner 作用域解析。
+func authorizeDocRefs(raw []byte, h extension.Host) []string {
+	var spec struct {
+		Nodes []core.UINode `json:"nodes"`
+	}
+	if err := json.Unmarshal(raw, &spec); err != nil {
+		return []string{"spec: " + err.Error()}
+	}
+	var errs []string
+	var walk func(n core.UINode, path string)
+	walk = func(n core.UINode, path string) {
+		if n.Type == core.UIDocRef && n.DocID != "" {
+			if _, err := h.ArtifactGet(string(n.DocID)); err != nil {
+				errs = append(errs, fmt.Sprintf("%s: doc-ref 引用了不存在或无权限的工件 %q", path, n.DocID))
+			}
+		}
+		for i, c := range n.Children {
+			walk(c, fmt.Sprintf("%s/child[%d]", path, i))
+		}
+		if n.Compare != nil {
+			for side, sd := range map[string]core.UICompareSide{"left": n.Compare.Left, "right": n.Compare.Right} {
+				for i, c := range sd.Nodes {
+					walk(c, fmt.Sprintf("%s/%s[%d]", path, side, i))
+				}
+			}
+		}
+		if n.Tabs != nil {
+			for i, tb := range n.Tabs.Tabs {
+				for j, c := range tb.Nodes {
+					walk(c, fmt.Sprintf("%s/tab[%d][%d]", path, i, j))
+				}
+			}
+		}
+	}
+	for i, n := range spec.Nodes {
+		walk(n, fmt.Sprintf("$[%d]", i))
+	}
+	return errs
+}

internal/genui/genui_test.go

@@ -0,0 +1,203 @@
+package genui
+
+// U3 红测（提案 U3 验证行）：能力缺失明确拒绝；未启用拒绝；伪造 doc-ref 拒绝；
+// 目录违规返回字段级清单（供模型修复重提）；成功路径经 EXT-17 提交并携带观察 epoch。
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"agent-system-backend/internal/store"
+	"agent-system-backend/internal/surfacesvc"
+	"agent-system-backend/pkg/extension"
+	core "agent-system-core"
+)
+
+// realSvc 让 fakeHost.SurfaceSave 走真实 surfacesvc（校验/守卫行为与生产一致）。
+var realSvc *surfacesvc.Service
+
+func newRealSvc(t *testing.T) {
+	t.Helper()
+	st, err := store.OpenSQLite(filepath.Join(t.TempDir(), "test.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { st.Close() })
+	realSvc = surfacesvc.New(st, nil)
+	if _, err := realSvc.SetActivation(context.Background(), "alice", PluginID, true); err != nil {
+		t.Fatal(err)
+	}
+}
+
+type fakeHost struct {
+	extension.Host // 未覆盖方法仅测试未触达
+	enabled        bool
+	epoch          int64
+	saved          []extension.SurfaceSaveRequest
+	artifacts      map[string]bool
+}
+
+func (h *fakeHost) SurfaceActivation(ctx context.Context) (bool, int64, error) {
+	return h.enabled, h.epoch, nil
+}
+
+func (h *fakeHost) SurfaceSave(ctx context.Context, req extension.SurfaceSaveRequest) (core.SurfaceSnapshot, error) {
+	h.saved = append(h.saved, req)
+	return realSvc.Submit(ctx, "alice", PluginID, surfacesvc.SubmitRequest{
+		SurfaceID: req.SurfaceID, ConversationID: req.ConversationID,
+		BaseRevision: req.BaseRevision, ObservedEpoch: req.ObservedEpoch,
+		SemanticText: req.SemanticText, Spec: req.Spec,
+	})
+}
+
+func (h *fakeHost) SurfaceGet(ctx context.Context, surfaceID core.ID) (core.SurfaceSnapshot, error) {
+	return realSvc.Get(ctx, "alice", surfaceID)
+}
+
+func (h *fakeHost) SurfaceList(ctx context.Context, conversationID core.ID) ([]core.SurfaceMeta, error) {
+	return realSvc.List(ctx, "alice", conversationID)
+}
+
+func (h *fakeHost) ArtifactGet(id string) (core.Artifact, error) {
+	if h.artifacts[id] {
+		return core.Artifact{ID: core.ID(id)}, nil
+	}
+	return core.Artifact{}, store.ErrNotFound
+}
+
+func validSpec() map[string]any {
+	return map[string]any{
+		"title": "选型对比",
+		"nodes": []any{
+			map[string]any{"type": "section", "id": "n1", "title": "概览", "children": []any{
+				map[string]any{"type": "markdown", "id": "n1a", "source": []any{"doc:a"}, "markdown": "结论先行。"},
+			}},
+			map[string]any{"type": "table", "id": "n2", "table": map[string]any{
+				"columns": []any{map[string]any{"key": "k", "label": "维度"}},
+				"rows":    []any{map[string]any{"cells": []any{[]any{"k", "价格"}}}},
+			}},
+		},
+	}
+}
+
+func reqWith(spec map[string]any, extra ...map[string]any) extension.Request {
+	params := map[string]any{"spec": spec}
+	for _, e := range extra {
+		for k, v := range e {
+			params[k] = v
+		}
+	}
+	return extension.Request{ID: "r1", Params: params, Owner: "alice", ConversationID: "c1"}
+}
+
+func TestPresentGuards(t *testing.T) {
+	newRealSvc(t)
+	ctx := context.Background()
+	// 能力缺失（Host 未实现 SurfaceHost）→ 明确报错
+	if _, err := present(ctx, plainHost{}, reqWith(validSpec())); err == nil {
+		t.Fatal("capability-missing host should fail explicitly")
+	}
+	// 未启用 → 拒绝
+	h := &fakeHost{enabled: false, artifacts: map[string]bool{}}
+	if _, err := present(ctx, h, reqWith(validSpec())); err == nil {
+		t.Fatal("disabled plugin should reject submit")
+	}
+	// 伪造 doc-ref：工件不存在 → 字段级工具错误
+	h = &fakeHost{enabled: true, epoch: 1, artifacts: map[string]bool{}}
+	spec := map[string]any{"title": "t", "nodes": []any{map[string]any{"type": "doc-ref", "docId": "art_ghost"}}}
+	res, err := present(ctx, h, reqWith(spec))
+	if err != nil {
+		t.Fatalf("doc-ref violation should be tool-error, got %v", err)
+	}
+	body, _ := json.Marshal(res)
+	if !strings.Contains(string(body), "art_ghost") {
+		t.Fatalf("field errors should name the bad docId: %s", body)
+	}
+	// 目录违规（未知字段 color）→ 字段级清单
+	bad := map[string]any{"title": "x", "nodes": []any{map[string]any{"type": "list", "items": []any{"a"}, "color": "red"}}}
+	res, err = present(ctx, h, reqWith(bad))
+	if err != nil {
+		t.Fatalf("invalid spec should be tool-error, got %v", err)
+	}
+	te, ok := res.(toolErrorBody)
+	if !ok || te.OK || len(te.Details) == 0 {
+		t.Fatalf("expected field-level details, got %+v", res)
+	}
+}
+
+func TestPresentSubmitCarriesEpochAndRevises(t *testing.T) {
+	newRealSvc(t)
+	ctx := context.Background()
+	h := &fakeHost{enabled: true, epoch: 1, artifacts: map[string]bool{}}
+	res, err := present(ctx, h, reqWith(validSpec()))
+	if err != nil {
+		t.Fatal(err)
+	}
+	m, _ := res.(map[string]any)
+	if m["ok"] != true || fmt.Sprint(m["revision"]) != "1" {
+		t.Fatalf("submit result: %+v", m)
+	}
+	if len(h.saved) != 1 || h.saved[0].ObservedEpoch != 1 {
+		t.Fatalf("submit must carry observed epoch: %+v", h.saved)
+	}
+	// 修订：带 surfaceId + baseRevision → revision 2
+	res2, err := present(ctx, h, reqWith(validSpec(), map[string]any{
+		"surfaceId": m["surfaceId"], "baseRevision": float64(1)}))
+	if err != nil {
+		t.Fatal(err)
+	}
+	m2, _ := res2.(map[string]any)
+	if fmt.Sprint(m2["revision"]) != "2" {
+		t.Fatalf("revision should advance to 2: %+v", m2)
+	}
+	// 禁用后：执行端拒绝（闸外第二道守卫）
+	h.enabled = false
+	if _, err := present(ctx, h, reqWith(validSpec())); err == nil {
+		t.Fatal("post-disable submit should reject")
+	}
+}
+
+func TestRegisterSpecShape(t *testing.T) {
+	var captured json.RawMessage
+	reg := &fakeRegistry{capture: &captured}
+	if err := register(reg); err != nil {
+		t.Fatal(err)
+	}
+	var spec struct {
+		ID           string         `json:"id"`
+		Description  string         `json:"description"`
+		ExposeAsTool map[string]any `json:"exposeAsTool"`
+		ParamsSchema map[string]any `json:"paramsSchema"`
+	}
+	if err := json.Unmarshal(captured, &spec); err != nil {
+		t.Fatal(err)
+	}
+	if spec.ID != CommandPresent || spec.ExposeAsTool == nil {
+		t.Fatalf("spec must expose as tool: %s", captured)
+	}
+	for _, need := range []string{"section{", "compare{", "steps{", "≤200 节点"} {
+		if !strings.Contains(spec.Description, need) {
+			t.Fatalf("catalog incomplete: missing %q", need)
+		}
+	}
+}
+
+type plainHost struct{ extension.Host }
+
+type fakeRegistry struct{ capture *json.RawMessage }
+
+func (r *fakeRegistry) AddCommandHandler(spec json.RawMessage, h extension.Handler) error {
+	*r.capture = spec
+	return nil
+}
+func (r *fakeRegistry) AddSkill(name, markdown string) error            { return nil }
+func (r *fakeRegistry) AddCommand(spec json.RawMessage) error           { return nil }
+func (r *fakeRegistry) Note(kind, name string, p json.RawMessage) error { return nil }
+func (r *fakeRegistry) RegisterResourceAuthorizer(fn extension.ResourceAuthorizer) error {
+	return nil
+}
+func (r *fakeRegistry) AddIntent(spec json.RawMessage) error { return nil }

internal/genui/replay_test.go

@@ -0,0 +1,251 @@
+package genui
+
+// U3 完成条件回放（真实模型，env 门控）：任务→规格→保存→（语义投影回灌）→
+// 继续修改→新修订。跑生产代码路径：present 处理器 + surfacesvc + store + ctxasm
+// 投影（AssembleOptions.Surfaces）。模型 MiniMax-M3（2026-10-11 裁定）。
+//
+// 启用：GENUI_MINIMAX_API_KEY=<key> go test ./internal/genui/ -run TestRealModelSurfaceLoop -v -count=1
+// 未设 env 时跳过（CI 无凭据；本地收据经 make evidence 记录）。
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+
+	"agent-system-backend/internal/ctxasm"
+	"agent-system-backend/internal/store"
+	"agent-system-backend/internal/surfacesvc"
+	"agent-system-backend/pkg/extension"
+	core "agent-system-core"
+)
+
+const materials = `材料：
+【doc:m1】甲方案：报价 ¥8/人/天；私有化可选；近半年发布 6 次，平均修复 2 天。
+【doc:m2】乙方案：报价 ¥12/人/天；仅 SaaS；万行表格场景无官方基准；升级断层（近两季仅小版本）。
+【doc:m3】尽调备忘：合规缺口（高）——数据出境条款未覆盖；培训成本（低）——术语不一致。`
+
+type chatResp struct {
+	Choices []struct {
+		Message struct {
+			ToolCalls []struct {
+				Function struct {
+					Name      string `json:"name"`
+					Arguments string `json:"arguments"`
+				} `json:"function"`
+			} `json:"tool_calls"`
+		} `json:"message"`
+	} `json:"choices"`
+	Usage struct {
+		PromptTokens     int `json:"prompt_tokens"`
+		CompletionTokens int `json:"completion_tokens"`
+	} `json:"usage"`
+}
+
+func callModelWithRepair(t *testing.T, ctx context.Context, system, user string, try func(map[string]any) (any, error)) (map[string]any, any, chatResp) {
+	t.Helper()
+	var usage chatResp
+	params, r := callModel(t, ctx, system, user)
+	usage.Usage.PromptTokens += r.Usage.PromptTokens
+	usage.Usage.CompletionTokens += r.Usage.CompletionTokens
+	res, err := try(params)
+	if err == nil {
+		if te, ok := res.(toolErrorBody); !ok || te.OK {
+			return params, res, usage
+		} else {
+			res = te
+		}
+	} else if res == nil {
+		t.Fatalf("dispatch error: %v", err)
+	}
+	// 修复轮：字段级错误回传，模型重提一次（KTD2）。
+	fixUser := user + "\n\n上一次提交被拒绝：" + fmt.Sprint(res) + "\n请修正后重新调用工具。"
+	params2, r2b := callModel(t, ctx, system, fixUser)
+	usage.Usage.PromptTokens += r2b.Usage.PromptTokens
+	usage.Usage.CompletionTokens += r2b.Usage.CompletionTokens
+	res2, err2 := try(params2)
+	if err2 != nil {
+		t.Fatalf("repair dispatch error: %v", err2)
+	}
+	if te, ok := res2.(toolErrorBody); ok && !te.OK {
+		t.Fatalf("repair still invalid: %+v", te)
+	}
+	return params2, res2, usage
+}
+
+func callModel(t *testing.T, ctx context.Context, system, user string) (map[string]any, chatResp) {
+	t.Helper()
+	key := os.Getenv("GENUI_MINIMAX_API_KEY")
+	tool := map[string]any{"type": "function", "function": map[string]any{
+		"name": CommandPresent, "description": Catalog, "parameters": map[string]any{
+			"type": "object",
+			"properties": map[string]any{
+				"spec":         map[string]any{"type": "object"},
+				"surfaceId":    map[string]any{"type": "string"},
+				"baseRevision": map[string]any{"type": "integer"},
+				"summary":      map[string]any{"type": "string"},
+			},
+			"required": []string{"spec"},
+		}}}
+	body, _ := json.Marshal(map[string]any{
+		"model": "MiniMax-M3", "temperature": 0.3, "max_tokens": 14000,
+		"tools": []any{tool}, "tool_choice": map[string]any{"type": "function", "function": map[string]any{"name": CommandPresent}},
+		"messages": []any{
+			map[string]any{"role": "system", "content": system},
+			map[string]any{"role": "user", "content": user},
+		}})
+	req, _ := http.NewRequestWithContext(ctx, "POST", "https://api.minimaxi.com/v1/chat/completions", bytes.NewReader(body))
+	req.Header.Set("Authorization", "Bearer "+key)
+	req.Header.Set("Content-Type", "application/json")
+	var out chatResp
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("model call: %v", err)
+	}
+	defer resp.Body.Close()
+	if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	if len(out.Choices) == 0 || len(out.Choices[0].Message.ToolCalls) == 0 {
+		t.Fatalf("no tool call in response")
+	}
+	var params map[string]any
+	if err := json.Unmarshal([]byte(out.Choices[0].Message.ToolCalls[0].Function.Arguments), &params); err != nil {
+		t.Fatalf("tool args: %v", err)
+	}
+	return params, out
+}
+
+func TestRealModelSurfaceLoop(t *testing.T) {
+	if os.Getenv("GENUI_MINIMAX_API_KEY") == "" {
+		t.Skip("GENUI_MINIMAX_API_KEY not set; real-model replay runs locally with recorded receipts")
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Minute)
+	defer cancel()
+	st, err := store.OpenSQLite(filepath.Join(t.TempDir(), "replay.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer st.Close()
+	svc := surfacesvc.New(st, nil)
+	if _, err := svc.SetActivation(ctx, "alice", PluginID, true); err != nil {
+		t.Fatal(err)
+	}
+	h := &realHost{svc: svc, artifacts: map[string]bool{}}
+
+	// 回合 1：任务→规格→保存
+	sys1 := "你是本产品中的助手。用户需要一页比较视图时，用 generative-ui.present 提交页面。"
+	try1 := func(p map[string]any) (any, error) {
+		return present(ctx, h, extension.Request{ID: "t1", Params: p, Owner: "alice", ConversationID: "c1"})
+	}
+	_, res1, r1 := callModelWithRepair(t, ctx, sys1, materials+"\n\n目标：给决策会准备风险分析页（按严重度组织，标注来源）。", try1)
+	m1, _ := res1.(map[string]any)
+	if m1["ok"] != true {
+		t.Fatalf("turn1 not accepted: %+v", res1)
+	}
+	snap1, err := svc.Get(ctx, "alice", core.ID(fmt.Sprint(m1["surfaceId"])))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Logf("turn1: surface=%s revision=%d nodes=%d tokens=%d/%d",
+		m1["surfaceId"], snap1.Revision, countNodes(snap1), r1.Usage.PromptTokens, r1.Usage.CompletionTokens)
+
+	// 回合 2：语义投影回灌 + 修订指令 → 新修订
+	msgs2, _ := ctxasm.AssembleInput(core.AgentProfile{}, nil, nil,
+		core.Message{Role: core.RoleUser, Parts: []core.Part{{Type: core.PartText, Text: "改为实施顺序"}}},
+		nil, nil, nil, nil, nil, nil, ctxasm.AssembleOptions{Surfaces: []core.SurfaceSnapshot{snap1}})
+	var sysParts []string
+	for _, m := range msgs2 {
+		if string(m.Role) == "system" {
+			sysParts = append(sysParts, m.Content)
+		}
+	}
+	sys2 := strings.Join(sysParts, "\n")
+	try2 := func(p map[string]any) (any, error) {
+		p["surfaceId"] = m1["surfaceId"]
+		p["baseRevision"] = float64(snap1.Revision)
+		return present(ctx, h, extension.Request{ID: "t2", Params: p, Owner: "alice", ConversationID: "c1"})
+	}
+	_, res2, r2 := callModelWithRepair(t, ctx, sys1+"\n"+sys2, materials+"\n\n目标：改为实施顺序（阶段与依赖），修订已有页面。", try2)
+	m2, _ := res2.(map[string]any)
+	if fmt.Sprint(m2["revision"]) != fmt.Sprint(snap1.Revision+1) {
+		t.Fatalf("turn2 should revise to %d, got %+v", snap1.Revision+1, res2)
+	}
+	snap2, _ := svc.Get(ctx, "alice", core.ID(fmt.Sprint(m1["surfaceId"])))
+	types2 := dominantTypes(snap2)
+	same := len(types2) == len(snap1.Spec.Nodes)
+	if same {
+		for i := range types2 {
+			if types2[i] != string(snap1.Spec.Nodes[i].Type) {
+				same = false
+				break
+			}
+		}
+	}
+	if len(snap2.Spec.Nodes) == 0 || (snap2.Spec.Title == snap1.Spec.Title && same) {
+		t.Fatalf("turn2 structure did not change: %v", types2)
+	}
+	t.Logf("turn2: revision=%d title=%q types=%v tokens=%d/%d",
+		snap2.Revision, snap2.Spec.Title, types2, r2.Usage.PromptTokens, r2.Usage.CompletionTokens)
+	totalIn := r1.Usage.PromptTokens + r2.Usage.PromptTokens
+	totalOut := r1.Usage.CompletionTokens + r2.Usage.CompletionTokens
+	cost := float64(totalIn)/1e6*0.3*7.2 + float64(totalOut)/1e6*1.2*7.2
+	t.Logf("cost: in=%d out=%d ≈¥%.3f (M3 $0.3/$1.2 per M, 7.2)", totalIn, totalOut, cost)
+}
+
+type realHost struct {
+	extension.Host
+	svc       *surfacesvc.Service
+	artifacts map[string]bool
+}
+
+func (h *realHost) SurfaceActivation(ctx context.Context) (bool, int64, error) {
+	row, err := h.svc.Activation(ctx, "alice", PluginID)
+	return row.Enabled, row.Epoch, err
+}
+func (h *realHost) SurfaceSave(ctx context.Context, req extension.SurfaceSaveRequest) (core.SurfaceSnapshot, error) {
+	return h.svc.Submit(ctx, "alice", PluginID, surfacesvc.SubmitRequest{
+		SurfaceID: req.SurfaceID, ConversationID: req.ConversationID, BaseRevision: req.BaseRevision,
+		ObservedEpoch: req.ObservedEpoch, SemanticText: req.SemanticText, Spec: req.Spec})
+}
+func (h *realHost) SurfaceGet(ctx context.Context, id core.ID) (core.SurfaceSnapshot, error) {
+	return h.svc.Get(ctx, "alice", id)
+}
+func (h *realHost) SurfaceList(ctx context.Context, cid core.ID) ([]core.SurfaceMeta, error) {
+	return h.svc.List(ctx, "alice", cid)
+}
+func (h *realHost) ArtifactGet(id string) (core.Artifact, error) {
+	if h.artifacts[id] {
+		return core.Artifact{ID: core.ID(id)}, nil
+	}
+	return core.Artifact{}, store.ErrNotFound
+}
+
+func countNodes(s core.SurfaceSnapshot) int {
+	var n int
+	var walk func(u core.UINode)
+	walk = func(u core.UINode) {
+		n++
+		for _, c := range u.Children {
+			walk(c)
+		}
+	}
+	for _, x := range s.Spec.Nodes {
+		walk(x)
+	}
+	return n
+}
+
+func dominantTypes(s core.SurfaceSnapshot) []string {
+	var out []string
+	for _, n := range s.Spec.Nodes {
+		out = append(out, string(n.Type))
+	}
+	return out
+}

internal/runmgr/command_tools_test.go

@@ -22,6 +22,8 @@ type fakeBusSource struct {
 
 func (f *fakeBusSource) CommandTools() []CommandTool { return f.cmds }
 
+func (f *fakeBusSource) CommandToolsFor(owner string) []CommandTool { return f.cmds }
+
 func (f *fakeBusSource) DispatchCommand(ctx context.Context, req CommandRequest) CommandResponse {
 	f.lastReq = req
 	return f.resp

internal/runmgr/runmgr.go

@@ -203,6 +203,8 @@ func (m *Manager) SetWorkspaceRoot(dir string) { m.workspaceRoot = dir }
 // 组合根以 cmdbus.Bus 适配注入（app.busAdapter 负责转换），runmgr 不依赖总线包。
 type CommandSource interface {
 	CommandTools() []CommandTool
+	// CommandToolsFor 按 owner 过滤工具投影（U3：禁用即不注入能力）。
+	CommandToolsFor(owner string) []CommandTool
 	DispatchCommand(ctx context.Context, req CommandRequest) CommandResponse
 }
 
@@ -258,6 +260,28 @@ type runCtx struct {
 	permissionMode string
 }
 
+// Surfaces 返回当前会话最近保存的生成页面（U3/R6：ctxasm 语义投影回灌；
+// 最近 5 页、新→旧；读路径不受启禁影响——禁用挡写入，不丢历史）。
+func (c *runCtx) Surfaces() []core.SurfaceSnapshot {
+	if c.mgr.st == nil || c.run.ConversationID == "" || c.run.Owner == "" {
+		return nil
+	}
+	metas, err := c.mgr.st.ListSurfaces(string(c.run.Owner), string(c.run.ConversationID))
+	if err != nil || len(metas) == 0 {
+		return nil
+	}
+	if len(metas) > 5 {
+		metas = metas[:5]
+	}
+	out := make([]core.SurfaceSnapshot, 0, len(metas))
+	for _, m := range metas {
+		if snap, err := c.mgr.st.GetSurfaceSnapshot(string(c.run.Owner), string(m.SurfaceID), 0); err == nil {
+			out = append(out, snap)
+		}
+	}
+	return out
+}
+
 // Workflow 返回这次 run 启动时拷贝的工作流。普通回合没有。
 func (c *runCtx) Workflow() (workflow.Launch, bool) {
 	if c.launch == nil {
@@ -437,7 +461,7 @@ func (c *runCtx) Tools() []core.ToolDesc {
 		for _, t := range list {
 			seen[t.Name] = true
 		}
-		for _, ct := range c.mgr.commands.CommandTools() {
+		for _, ct := range c.mgr.commands.CommandToolsFor(string(c.run.Owner)) {
 			if seen[ct.ID] {
 				continue
 			}
@@ -874,7 +898,7 @@ func (c *runCtx) ExecuteTool(call core.ToolCallRequest) core.ToolCallResult {
 	// EXT-14：命令即工具——命中命令投影时经命令总分发（Entrance=agent、
 	// Actor/Owner=会话 owner、带会话上下文），同审计信封与高危确认卡收口。
 	if c.mgr.commands != nil {
-		for _, ct := range c.mgr.commands.CommandTools() {
+		for _, ct := range c.mgr.commands.CommandToolsFor(string(c.run.Owner)) {
 			if ct.ID != call.Name {
 				continue
 			}

internal/runtime/llm.go

@@ -270,6 +270,7 @@ func (l *LLMRunner) Execute(rc RunCtx) error {
 	// 组装侧不再注入（防双份；注入文案同一形态）。
 	_ = ctxasm.InjectMemory
 	msgs, asmReport := ctxasm.AssembleInput(prof, eff, hist, currentUser, rc.Attachments(), knowledge, sys, promptObs, rc.Card, resolveArtifact, ctxasm.AssembleOptions{
+		Surfaces:    rc.Surfaces(),
 		ThinkReplay: thinkReplayEnabled(eff, route.Model),
 	})
 	tail := ctxasm.Tail{

internal/runtime/llm_test.go

@@ -1117,3 +1117,5 @@ func transcriptOf(msgs []agentllm.Message) string {
 	}
 	return b.String()
 }
+
+func (f *fakeRunCtx) Surfaces() []core.SurfaceSnapshot { return nil }

internal/runtime/runner.go

@@ -50,6 +50,8 @@ type RunCtx interface {
 	Card(id string) *core.ActivityCard
 	// Artifact：按 ID 取工件与内容（ctxasm 回填 artifact_ref 正文用；无则 false）。
 	Artifact(id string) (core.Artifact, []byte, bool)
+	// Surfaces 返回当前会话最近保存的生成页面（U3/R6：ctxasm 语义投影回灌）。
+	Surfaces() []core.SurfaceSnapshot
 	// SetContextObservation 记录本次运行的上下文组装观测（随 run.completed 下发）。
 	SetContextObservation(o core.ContextObservation)
 }

internal/runtime/squad_runner_test.go

@@ -461,3 +461,5 @@ func containsStr(list []string, want string) bool {
 	}
 	return false
 }
+
+func (*entryFake) Surfaces() []core.SurfaceSnapshot { return nil }

internal/runtime/workflow_compiled_test.go

@@ -291,3 +291,5 @@ func TestJudgeStreamUsesConfiguredModel(t *testing.T) {
 		t.Fatal("未配置模型应为 nil（验证器不可用 fail-closed）")
 	}
 }
+
+func (*wfFake) Surfaces() []core.SurfaceSnapshot { return nil }