diff --git a/go.mod b/go.mod
index b84eccb..e18f2d5 100644
--- a/go.mod
+++ b/go.mod
@@ -3,15 +3,18 @@ module agent-system-backend
 go 1.27
 
 require (
+	agent-command v0.0.0
 	agent-intent v0.0.0
 	agent-native v0.0.0
+	agent-squad v0.0.0-00010101000000-000000000000
 	agent-system-core v0.0.0
+	github.com/jackc/pgx/v5 v5.7.6
 	github.com/ledongthuc/pdf v0.0.0-20260907135840-6c8c28e0e8a0
+	github.com/redis/go-redis/v9 v9.14.0
 	modernc.org/sqlite v1.60.1
 )
 
 require (
-	agent-squad v0.0.0-00010101000000-000000000000 // indirect
 	error-code-system v0.0.0 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
@@ -19,11 +22,9 @@ require (
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
-	github.com/jackc/pgx/v5 v5.7.6 // indirect
 	github.com/jackc/puddle/v2 v2.2.2 // indirect
 	github.com/mattn/go-isatty v0.0.24 // indirect
 	github.com/ncruces/go-strftime v1.0.0 // indirect
-	github.com/redis/go-redis/v9 v9.14.0 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
 	golang.org/x/crypto v0.37.0 // indirect
 	golang.org/x/sync v0.23.0 // indirect
diff --git a/go.sum b/go.sum
index 535e370..15b9529 100644
--- a/go.sum
+++ b/go.sum
@@ -1,6 +1,12 @@
+github.com/bsm/ginkgo/v2 v2.12.0 h1:Ny8MWAHyOepLGlLKYmXG4IEkioBysk6GpaRTLC8zwWs=
+github.com/bsm/ginkgo/v2 v2.12.0/go.mod h1:SwYbGRRDovPVboqFv0tPTcG1sN61LM1Z4ARdbAV9g4c=
+github.com/bsm/gomega v1.27.10 h1:yeMWxP2pV2fG3FgAODIY8EiRE3dy0aeFYt4l7wh6yKA=
+github.com/bsm/gomega v1.27.10/go.mod h1:JyEr/xRbxbtgWNi8tIEVPUYZ5Dzef52k01W3YH0H+O0=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
@@ -25,6 +31,7 @@ github.com/mattn/go-isatty v0.0.24 h1:tGZZoVgT/KiqK1c8ocVLeDS8BSWMRd47J3Lbz7vsRe
 github.com/mattn/go-isatty v0.0.24/go.mod h1:nMCL3Zebbrt45jsMDgnfIwz6ydEQApk5oEI3HqDio6A=
 github.com/ncruces/go-strftime v1.0.0 h1:HMFp8mLCTPp341M/ZnA4qaf7ZlsbTc+miZjCLOFAw7w=
 github.com/ncruces/go-strftime v1.0.0/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/redis/go-redis/v9 v9.14.0 h1:u4tNCjXOyzfgeLN+vAZaW1xUooqWDqVEsZN0U01jfAE=
 github.com/redis/go-redis/v9 v9.14.0/go.mod h1:huWgSWd8mW6+m0VPhJjSSQ+d6Nh1VICQ6Q5lHuCH/Iw=
@@ -33,6 +40,8 @@ github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec/go.mod h1:qq
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
+github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 golang.org/x/crypto v0.37.0 h1:kJNSjF/Xp7kU0iB2Z+9viTPMW4EqqsrywMXLJOOsXSE=
 golang.org/x/crypto v0.37.0/go.mod h1:vg+k43peMZ0pUMhYmVAWysMK35e6ioLh3wB8ZCAfbVc=
 golang.org/x/mod v0.41.0 h1:qJmnOUb4YB+FsEuM3HcWucdZASCPGhsX6uljO6pog0c=
@@ -47,6 +56,8 @@ golang.org/x/tools v0.50.0 h1:c2ifzfcuY7L90lZ2aKd8S4K2NpASF08SZx9ZuJkHmSU=
 golang.org/x/tools v0.50.0/go.mod h1:7ulVMw3831Mwi5EZD6RomGyffr4VFjuNYXf2BbCEAV0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 modernc.org/cc/v4 v4.29.7 h1:q+NXGJ0bK3b4TXFYQQVr9pYETGnmwFWkrUzJnMya/Tg=
 modernc.org/cc/v4 v4.29.7/go.mod h1:OnovgIhbbMXMu1aISnJ0wvVD1KnW+cAUJkIrAWh+kVI=
 modernc.org/ccgo/v4 v4.36.1 h1:ZNIUZAryN0UgnJwtyxrdEzcFc3yD4Cu4AzjfPXsLsIE=
diff --git a/internal/app/app.go b/internal/app/app.go
index 04bc612..b2908fb 100644
--- a/internal/app/app.go
+++ b/internal/app/app.go
@@ -17,6 +17,7 @@ import (
 
 	"agent-system-backend/internal/bus"
 	"agent-system-backend/internal/cardsvc"
+	"agent-system-backend/internal/cmdbus"
 	"agent-system-backend/internal/intentgate"
 	"agent-system-backend/internal/pgbus"
 	"agent-system-backend/internal/plugins"
@@ -106,8 +107,15 @@ func Run(opt Options) error {
 	cardSvc := cardsvc.New(st, mgr.EmitCardEvent)
 	mgr.SetCards(cardSvc)
 
+	// 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() })
+	pluginHost.OnCommands = bus.RegisterPluginCommands
+
 	srv := server.New(st, mgr, reg, profSvc, setSvc, pluginHost)
 	srv.Cards = cardSvc
+	srv.Bus = bus
+	srv.Gate = gate
+	srv.WireBuiltinCommands()
 	srv.Retriever = pipe
 	srv.Indexer = pipe
 
diff --git a/internal/cmdbus/cmdbus.go b/internal/cmdbus/cmdbus.go
new file mode 100644
index 0000000..b9a5bf1
--- /dev/null
+++ b/internal/cmdbus/cmdbus.go
@@ -0,0 +1,332 @@
+// Package cmdbus 组合 Agent-Command 生态库：注册、四入口分发（button/card/slash/chat→api
+// 归一）、审计信封落盘与危险命令的内联确认卡收口（提案 T3 / D27、D30、D33）。
+// 与 intentgate 之于 agent-intent 同构：schema 权威在生态库，宿主只做装配与执行适配。
+package cmdbus
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+
+	agentcommand "agent-command"
+	"agent-system-core"
+)
+
+// AuditStore 审计落盘端口（store 实现；v7 command_audit）。
+type AuditStore interface {
+	AppendAudit(env agentcommand.AuditEnvelope) error
+}
+
+// CardPort 确认卡所需卡片能力（cardsvc.Service 实现）。
+type CardPort interface {
+	Create(owner string, card core.ActivityCard, ref string) (core.ActivityCard, error)
+	SetStatus(owner, id string, status core.CardStatus, tone, note string) (core.ActivityCard, error)
+}
+
+// Handler 宿主执行适配器：同步内置用例返回 payload；异步执行自行返回 accepted 回执。
+type Handler func(ctx context.Context, req Request) (any, error)
+
+// Request 一次分发请求（入口归一后的统一形态）。
+type Request struct {
+	ID              string
+	Params          map[string]any
+	Entrance        string // button | card | slash | chat | api（归一）
+	Actor           string
+	Owner           string
+	ConversationID  string
+	AnchorMessageID string // 确认卡锚定的发起消息（内联渲染）
+	Confirmed       bool   // 危险命令经确认卡放行后的执行
+}
+
+// Response 分发结果：回执 + 处理负载 + 可能的确认卡。
+type Response struct {
+	Receipt agentcommand.ExecReceipt
+	Payload any
+	Card    *core.ActivityCard // 高危未确认时创建的内联确认卡
+}
+
+// pending 确认卡挂起的执行（进程内；重启后确认返回 rejected expired——v1 限制）。
+type pending struct {
+	req    Request
+	cardID string
+}
+
+type Bus struct {
+	reg      *agentcommand.Registry
+	audit    AuditStore
+	cards    CardPort
+	now      func() time.Time
+	handlers map[string]Handler
+	slash    map[string]string // "/x" → command id
+	pendMu   sync.Mutex
+	pending  map[string]pending
+}
+
+func New(audit AuditStore, cards CardPort, now func() time.Time) *Bus {
+	if now == nil {
+		now = time.Now
+	}
+	return &Bus{
+		reg: agentcommand.NewRegistry(), audit: audit, cards: cards, now: now,
+		handlers: map[string]Handler{}, slash: map[string]string{}, pending: map[string]pending{},
+	}
+}
+
+// Registry 暴露注册表（列清单/插件 overlay 注册用）。
+func (b *Bus) Registry() *agentcommand.Registry { return b.reg }
+
+// RegisterBuiltin 登记内置命令并绑定宿主处理器与 `/` 别名。
+func (b *Bus) RegisterBuiltin(spec agentcommand.CommandSpec, slash string, h Handler) error {
+	spec.Binding = agentcommand.Binding{Kind: agentcommand.BindBuiltin}
+	if err := b.reg.Register(spec, agentcommand.SourceBuiltin); err != nil {
+		return err
+	}
+	if h != nil {
+		b.handlers[spec.ID] = h
+	}
+	if slash != "" {
+		b.slash[strings.ToLower(slash)] = spec.ID
+	}
+	return nil
+}
+
+// RegisterPluginCommands 插件命令 overlay（manifest provides.commands；失败 fail-closed 返回）。
+func (b *Bus) RegisterPluginCommands(overlay []json.RawMessage) error {
+	for _, raw := range overlay {
+		var spec agentcommand.CommandSpec
+		if err := json.Unmarshal(raw, &spec); err != nil {
+			return fmt.Errorf("cmdbus: plugin command spec: %w", err)
+		}
+		if err := b.reg.Register(spec, agentcommand.SourcePlugin); err != nil {
+			return fmt.Errorf("cmdbus: register %s: %w", spec.ID, err)
+		}
+	}
+	return nil
+}
+
+// ResolveSlash `/` 入口解析：返回命令 id 与原始字段（参数由宿主处理器按命令语义解析）。
+func (b *Bus) ResolveSlash(cmd string) (string, bool) {
+	id, ok := b.slash[strings.ToLower(strings.TrimSpace(cmd))]
+	return id, ok
+}
+
+// SlashTable slash 别名表（清单组装用；只读副本）。
+func (b *Bus) SlashTable() map[string]string {
+	out := make(map[string]string, len(b.slash))
+	for k, v := range b.slash {
+		out[k] = v
+	}
+	return out
+}
+
+// HasCommand 同源判定（intentgate 命中意图后查总线是否承接）。
+func (b *Bus) HasCommand(id string) bool {
+	_, _, err := b.reg.Resolve(id)
+	return err == nil
+}
+
+// List 四入口共享的命令清单（`/` 菜单、按钮、卡片 action 提示用）。
+func (b *Bus) List() []agentcommand.Registered { return b.reg.List() }
+
+// Dispatch 统一分发：校验→危险收口→执行→审计。任何路径都产出回执与审计（入口对称）。
+func (b *Bus) Dispatch(ctx context.Context, req Request) Response {
+	start := b.now()
+	req.Entrance = agentcommand.CanonicalEntrance(req.Entrance)
+	receipt := func(state agentcommand.ResultState, op, reason string) Response {
+		return Response{Receipt: b.auditReceipt(req, state, op, reason, start)}
+	}
+	spec, _, err := b.reg.Resolve(req.ID)
+	if err != nil {
+		return receipt(agentcommand.StateRejected, "", "unknown or disabled command: "+req.ID)
+	}
+	if err := validateParams(spec.ParamsSchema, req.Params); err != nil {
+		return receipt(agentcommand.StateRejected, "", "params: "+err.Error())
+	}
+	// 高危收口：非确认入口先落内联确认卡（committed 语义 = 卡已创建；确认后二次分发执行）。
+	if spec.Danger == agentcommand.DangerHigh && !req.Confirmed {
+		if b.cards == nil || req.ConversationID == "" {
+			return receipt(agentcommand.StateRejected, "", "high-danger command requires conversation context for inline confirm")
+		}
+		card, err := b.cards.Create(req.Owner, confirmCard(spec, req), "cmd:"+spec.ID)
+		if err != nil {
+			return receipt(agentcommand.StateUnknown, "", "confirm card: "+err.Error())
+		}
+		b.pendMu.Lock()
+		b.pending[card.ID] = pending{req: req, cardID: card.ID}
+		b.pendMu.Unlock()
+		r := b.auditReceipt(req, agentcommand.StateAccepted, card.ID, "awaiting explicit confirm", start)
+		return Response{Receipt: r, Card: &card}
+	}
+	h, ok := b.handlers[req.ID]
+	if !ok {
+		return receipt(agentcommand.StateRejected, "", "no host handler bound for "+req.ID)
+	}
+	payload, err := h(ctx, req)
+	if err != nil {
+		return receipt(agentcommand.StateRejected, "", "rejected: "+err.Error())
+	}
+	op := fmt.Sprintf("op_%s_%d", strings.ReplaceAll(strings.TrimPrefix(req.ID, ""), ".", "_"), b.now().UnixNano())
+	return Response{Receipt: b.auditReceipt(req, agentcommand.StateCommitted, op, "", start), Payload: payload}
+}
+
+// Confirm 确认卡回道：actionID=confirm 执行挂起请求（entrance 归一 card），其余视为取消。
+func (b *Bus) Confirm(owner, cardID, actionID string) Response {
+	b.pendMu.Lock()
+	p, ok := b.pending[cardID]
+	if ok && actionID == "confirm" {
+		delete(b.pending, cardID)
+	}
+	b.pendMu.Unlock()
+	if !ok {
+		return Response{Receipt: agentcommand.ExecReceipt{CommandID: "unknown", State: agentcommand.StateRejected, Reason: "no pending confirm (expired or already resolved)", Time: b.now().UTC()}}
+	}
+	req := p.req
+	req.Confirmed = true
+	req.Entrance = "card"
+	if actionID != "confirm" {
+		if b.cards != nil {
+			_, _ = b.cards.SetStatus(owner, cardID, core.CardResolved, "muted", "cancelled")
+		}
+		start := b.now()
+		return Response{Receipt: b.auditReceipt(req, agentcommand.StateRejected, "", "cancelled at confirm card", start)}
+	}
+	resp := b.Dispatch(context.Background(), req)
+	if b.cards != nil {
+		if resp.Receipt.State == agentcommand.StateCommitted {
+			_, _ = b.cards.SetStatus(owner, cardID, core.CardResolved, "ok", "confirmed")
+		} else {
+			_, _ = b.cards.SetStatus(owner, cardID, core.CardFailed, "danger", resp.Receipt.Reason)
+		}
+	}
+	return resp
+}
+
+func (b *Bus) auditReceipt(req Request, state agentcommand.ResultState, op, reason string, start time.Time) agentcommand.ExecReceipt {
+	env := agentcommand.AuditEnvelope{
+		Time: start.UTC(), Actor: req.Actor, CommandID: req.ID, Entrance: agentcommand.CanonicalEntrance(req.Entrance),
+		ParamsDigest: digest(req.Params), State: state, DurationMs: float64(b.now().Sub(start).Milliseconds()),
+		OperationID: op, ConversationID: req.ConversationID,
+	}
+	if _, src, err := b.reg.Resolve(req.ID); err == nil {
+		env.Source = src
+	}
+	if err := b.audit.AppendAudit(env); err != nil {
+		// 审计不可用：结果标记未知，不臆断成功（四态语义）。
+		return agentcommand.ExecReceipt{CommandID: req.ID, State: agentcommand.StateUnknown, Reason: "audit unavailable: " + err.Error(), Time: b.now().UTC()}
+	}
+	return agentcommand.ExecReceipt{CommandID: req.ID, State: state, OperationID: op, Reason: reason, Time: b.now().UTC()}
+}
+
+func digest(params map[string]any) string {
+	if len(params) == 0 {
+		return ""
+	}
+	raw, _ := json.Marshal(params)
+	sum := sha256.Sum256(raw)
+	return hex.EncodeToString(sum[:8])
+}
+
+// confirmCard 构造内联确认卡：锚定发起消息、双现于收件箱、动作收口回总线。
+func confirmCard(spec agentcommand.CommandSpec, req Request) core.ActivityCard {
+	body := []core.UINode{{Type: core.UIMarkdown, Markdown: "**" + spec.Title + "** 需要确认后执行。"}}
+	if spec.Description != "" {
+		body = append(body, core.UINode{Type: core.UIMarkdown, Markdown: spec.Description})
+	}
+	rows := [][2]string{{"入口", req.Entrance}}
+	for k, v := range req.Params {
+		rows = append(rows, [2]string{k, fmt.Sprintf("%v", v)})
+	}
+	body = append(body, core.UINode{Type: core.UIKV, KV: rows})
+	return core.ActivityCard{
+		Kind: core.CardKindConfirm, Status: core.CardActionRequired, Tone: "warn",
+		Title: "确认执行：" + spec.Title,
+		Body:  body,
+		Actions: []core.UIAction{
+			{ID: "confirm", Label: "确认执行", Style: "primary"},
+			{ID: "cancel", Label: "取消", Style: "danger"},
+		},
+		ConversationID:  core.ID(req.ConversationID),
+		AnchorMessageID: core.ID(req.AnchorMessageID),
+	}
+}
+
+// validateParams JSON Schema draft-07 子集（type:object + required + 标量类型），宿主侧校验。
+func validateParams(schema json.RawMessage, params map[string]any) error {
+	if len(schema) == 0 {
+		return nil
+	}
+	var sc struct {
+		Type       string         `json:"type"`
+		Required   []string       `json:"required"`
+		Properties map[string]any `json:"properties"`
+	}
+	if err := json.Unmarshal(schema, &sc); err != nil {
+		return fmt.Errorf("bad schema: %w", err)
+	}
+	if sc.Type != "" && sc.Type != "object" {
+		return fmt.Errorf("schema type must be object, got %s", sc.Type)
+	}
+	for _, k := range sc.Required {
+		if _, ok := params[k]; !ok {
+			return fmt.Errorf("missing required param %s", k)
+		}
+	}
+	for k, v := range params {
+		decl, ok := sc.Properties[k]
+		if !ok {
+			continue // 未声明属性放行（宿主最小校验）
+		}
+		m, _ := decl.(map[string]any)
+		want, _ := m["type"].(string)
+		if want != "" && !scalarTypeOk(want, v) {
+			return fmt.Errorf("param %s: want %s", k, want)
+		}
+	}
+	return nil
+}
+
+func scalarTypeOk(want string, v any) bool {
+	switch want {
+	case "string":
+		_, ok := v.(string)
+		return ok
+	case "number":
+		return isNum(v)
+	case "boolean":
+		_, ok := v.(bool)
+		return ok
+	case "integer":
+		if !isNum(v) {
+			return false
+		}
+		return float64(toFloat(v)) == float64(int64(toFloat(v)))
+	}
+	return true
+}
+
+func isNum(v any) bool {
+	switch v.(type) {
+	case float64, float32, int, int64:
+		return true
+	}
+	return false
+}
+
+func toFloat(v any) float64 {
+	switch x := v.(type) {
+	case float64:
+		return x
+	case float32:
+		return float64(x)
+	case int:
+		return float64(x)
+	case int64:
+		return float64(x)
+	}
+	return 0
+}
diff --git a/internal/cmdbus/cmdbus_test.go b/internal/cmdbus/cmdbus_test.go
new file mode 100644
index 0000000..8feb8cf
--- /dev/null
+++ b/internal/cmdbus/cmdbus_test.go
@@ -0,0 +1,213 @@
+package cmdbus
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	agentcommand "agent-command"
+	"agent-system-core"
+)
+
+// memAudit / memCards 测试替身。
+type memAudit struct {
+	mu   sync.Mutex
+	logs []agentcommand.AuditEnvelope
+	fail bool
+}
+
+func (m *memAudit) AppendAudit(env agentcommand.AuditEnvelope) error {
+	if m.fail {
+		return errors.New("audit down")
+	}
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.logs = append(m.logs, env)
+	return nil
+}
+
+type memCards struct{ created []core.ActivityCard }
+
+func (m *memCards) Create(owner string, c core.ActivityCard, ref string) (core.ActivityCard, error) {
+	c.ID = core.ID("card_x1")
+	m.created = append(m.created, c)
+	return c, nil
+}
+func (m *memCards) SetStatus(owner, id string, st core.CardStatus, tone, note string) (core.ActivityCard, error) {
+	return core.ActivityCard{ID: core.ID(id), Status: st}, nil
+}
+
+func newTestBus(a AuditStore, c CardPort) *Bus {
+	b := New(a, c, func() time.Time { return time.Unix(1700000000, 0).UTC() })
+	_ = b.RegisterBuiltin(agentcommand.CommandSpec{ID: "demo.ping", Title: "Ping"}, "/ping",
+		func(ctx context.Context, req Request) (any, error) { return map[string]any{"pong": true}, nil })
+	_ = b.RegisterBuiltin(agentcommand.CommandSpec{
+		ID: "demo.risky", Title: "危险演示", Danger: agentcommand.DangerHigh,
+		Description: "高危命令演示",
+		ParamsSchema: json.RawMessage(`{"type":"object","required":["target"],"properties":{"target":{"type":"string"}}}`),
+	}, "/risky", func(ctx context.Context, req Request) (any, error) {
+		t, _ := req.Params["target"].(string)
+		if t == "boom" {
+			return nil, errors.New("handler rejected")
+		}
+		return map[string]any{"did": t}, nil
+	})
+	return b
+}
+
+func TestDispatchFourEntrancesSameAudit(t *testing.T) {
+	a := &memAudit{}
+	b := newTestBus(a, &memCards{})
+	for _, ent := range []string{"button", "slash", "chat", "card", "api", "weird-unknown"} {
+		resp := b.Dispatch(context.Background(), Request{ID: "demo.ping", Entrance: ent})
+		if resp.Receipt.State != agentcommand.StateCommitted {
+			t.Fatalf("entrance %s: state=%s reason=%s", ent, resp.Receipt.State, resp.Receipt.Reason)
+		}
+	}
+	if len(a.logs) != 6 {
+		t.Fatalf("audit logs = %d, want 6", len(a.logs))
+	}
+	want := map[string]string{"button": "button", "slash": "slash", "chat": "chat", "card": "card", "api": "api", "weird-unknown": "api"}
+	for i, env := range a.logs {
+		if env.Source != agentcommand.SourceBuiltin {
+			t.Fatalf("log %d source = %s", i, env.Source)
+		}
+	}
+	_ = want
+	// 入口归一：未知名归 api
+	if got := a.logs[5].Entrance; got != "api" {
+		t.Fatalf("unknown entrance canonicalized to %s, want api", got)
+	}
+	if a.logs[0].OperationID == "" {
+		t.Fatal("committed receipt must carry operationID")
+	}
+}
+
+func TestDispatchUnknownAndBadParams(t *testing.T) {
+	a := &memAudit{}
+	b := newTestBus(a, &memCards{})
+	resp := b.Dispatch(context.Background(), Request{ID: "nope.x"})
+	if resp.Receipt.State != agentcommand.StateRejected || !strings.Contains(resp.Receipt.Reason, "unknown") {
+		t.Fatalf("unknown: %+v", resp.Receipt)
+	}
+	resp = b.Dispatch(context.Background(), Request{ID: "demo.risky", Confirmed: true, Params: map[string]any{}})
+	if resp.Receipt.State != agentcommand.StateRejected || !strings.Contains(resp.Receipt.Reason, "required param target") {
+		t.Fatalf("missing required: %+v", resp.Receipt)
+	}
+}
+
+func TestHighDangerConfirmFlow(t *testing.T) {
+	a := &memAudit{}
+	cards := &memCards{}
+	b := newTestBus(a, cards)
+
+	// 未确认：创建内联确认卡，回执 accepted + operationID=卡 ID。
+	resp := b.Dispatch(context.Background(), Request{ID: "demo.risky", Params: map[string]any{"target": "prod"}, Entrance: "button", ConversationID: "cnv_1", AnchorMessageID: "msg_1"})
+	if resp.Receipt.State != agentcommand.StateAccepted || resp.Receipt.OperationID != "card_x1" {
+		t.Fatalf("pre-confirm: %+v", resp.Receipt)
+	}
+	if resp.Card == nil || resp.Card.Kind != core.CardKindConfirm || resp.Card.Status != core.CardActionRequired {
+		t.Fatalf("confirm card not created properly: %+v", resp.Card)
+	}
+	if resp.Card.ConversationID != "cnv_1" || resp.Card.AnchorMessageID == "" {
+		t.Fatalf("card anchoring missing: %+v", resp.Card)
+	}
+
+	// 确认：执行挂起请求，committed。
+	resp2 := b.Confirm("owner", "card_x1", "confirm")
+	if resp2.Receipt.State != agentcommand.StateCommitted {
+		t.Fatalf("confirm: %+v", resp2.Receipt)
+	}
+	if m, _ := resp2.Payload.(map[string]any); m == nil || m["did"] != "prod" {
+		t.Fatalf("confirm payload: %+v", resp2.Payload)
+	}
+
+	// 二次确认（已消费）：rejected expired。
+	resp3 := b.Confirm("owner", "card_x1", "confirm")
+	if resp3.Receipt.State != agentcommand.StateRejected || !strings.Contains(resp3.Receipt.Reason, "expired") {
+		t.Fatalf("re-confirm: %+v", resp3.Receipt)
+	}
+
+	// 审计链：accepted(button) → committed(card)；过期确认未触碰命令，不产生审计。
+	if len(a.logs) != 2 {
+		t.Fatalf("audit logs = %d, want 2", len(a.logs))
+	}
+	if a.logs[0].State != agentcommand.StateAccepted || a.logs[0].Entrance != "button" ||
+		a.logs[1].State != agentcommand.StateCommitted || a.logs[1].Entrance != "card" {
+		t.Fatalf("audit chain wrong: %+v", a.logs)
+	}
+}
+
+func TestHighDangerCancelAndHandlerReject(t *testing.T) {
+	a := &memAudit{}
+	b := newTestBus(a, &memCards{})
+	b.Dispatch(context.Background(), Request{ID: "demo.risky", Params: map[string]any{"target": "x"}, ConversationID: "cnv_1"})
+	if r := b.Confirm("o", "card_x1", "cancel"); r.Receipt.State != agentcommand.StateRejected || !strings.Contains(r.Receipt.Reason, "cancelled") {
+		t.Fatalf("cancel: %+v", r.Receipt)
+	}
+	// handler 拒绝路径（确认后执行失败）→ rejected + 理由。
+	b.Dispatch(context.Background(), Request{ID: "demo.risky", Params: map[string]any{"target": "boom"}, ConversationID: "cnv_1"})
+	r := b.Confirm("o", "card_x1", "confirm")
+	if r.Receipt.State != agentcommand.StateRejected || !strings.Contains(r.Receipt.Reason, "handler rejected") {
+		t.Fatalf("handler reject: %+v", r.Receipt)
+	}
+}
+
+func TestHighDangerWithoutCardPortRejected(t *testing.T) {
+	b := newTestBus(&memAudit{}, nil)
+	resp := b.Dispatch(context.Background(), Request{ID: "demo.risky", Params: map[string]any{"target": "x"}, ConversationID: "cnv_1"})
+	if resp.Receipt.State != agentcommand.StateRejected || !strings.Contains(resp.Receipt.Reason, "conversation context") {
+		t.Fatalf("no card port: %+v", resp.Receipt)
+	}
+}
+
+func TestAuditUnavailableYieldsUnknown(t *testing.T) {
+	a := &memAudit{fail: true}
+	b := newTestBus(a, &memCards{})
+	resp := b.Dispatch(context.Background(), Request{ID: "demo.ping"})
+	if resp.Receipt.State != agentcommand.StateUnknown || !strings.Contains(resp.Receipt.Reason, "audit unavailable") {
+		t.Fatalf("audit down: %+v", resp.Receipt)
+	}
+}
+
+func TestPluginCommandsAndSlash(t *testing.T) {
+	b := newTestBus(&memAudit{}, &memCards{})
+	if err := b.RegisterPluginCommands([]json.RawMessage{json.RawMessage(`{"id":"plug.do","title":"插件命令"}`)}); err != nil {
+		t.Fatal(err)
+	}
+	if err := b.RegisterPluginCommands([]json.RawMessage{json.RawMessage(`{"id":"bad id","title":"x"}`)}); err == nil {
+		t.Fatal("invalid plugin spec must be rejected")
+	}
+	if id, ok := b.ResolveSlash("/risky"); !ok || id != "demo.risky" {
+		t.Fatalf("slash resolve: %s %v", id, ok)
+	}
+	if _, ok := b.ResolveSlash("/nope"); ok {
+		t.Fatal("unknown slash must not resolve")
+	}
+	if !b.HasCommand("plug.do") || b.HasCommand("plug.missing") {
+		t.Fatal("HasCommand wrong")
+	}
+}
+
+func TestValidateParamsScalars(t *testing.T) {
+	schema := json.RawMessage(`{"type":"object","required":["n"],"properties":{"n":{"type":"number"},"s":{"type":"string"},"b":{"type":"boolean"},"i":{"type":"integer"}}}`)
+	if err := validateParams(schema, map[string]any{"n": 1.5, "s": "x", "b": true, "i": 3}); err != nil {
+		t.Fatalf("valid params rejected: %v", err)
+	}
+	if err := validateParams(schema, map[string]any{}); err == nil || !strings.Contains(err.Error(), "required") {
+		t.Fatalf("missing required not caught: %v", err)
+	}
+	if err := validateParams(schema, map[string]any{"n": "not-a-number"}); err == nil {
+		t.Fatal("type mismatch not caught")
+	}
+	if err := validateParams(schema, map[string]any{"n": 1, "i": 2.5}); err == nil {
+		t.Fatal("integer fraction not caught")
+	}
+	if err := validateParams(nil, map[string]any{"any": 1}); err != nil {
+		t.Fatalf("nil schema must pass: %v", err)
+	}
+}
diff --git a/internal/plugins/host.go b/internal/plugins/host.go
index 4c431a5..bc08506 100644
--- a/internal/plugins/host.go
+++ b/internal/plugins/host.go
@@ -26,6 +26,7 @@ type Loaded struct {
 	Cards    map[string][]core.UINode // kind → 模板节点
 	Workflows []core.WorkflowDef
 	Intents  []json.RawMessage // agent-intent overlay 形态（目录侧消费）
+	Commands []json.RawMessage // Agent-Command spec overlay（cmdbus 注册）
 	Prompts  map[string]string // 文件名 → 内容（画像模板）
 	PluginSettings []core.SettingDesc
 	Defaults map[string]any // 插件设置默认值（并入有效设置）
@@ -41,6 +42,8 @@ type Host struct {
 	loaded   map[string]*Loaded // id → loaded
 	// OnIntents 在装载集合变化后回调全部意图 overlay（宿主接识别闸门；nil = 不接）。
 	OnIntents func(overlay []json.RawMessage) error
+	// OnCommands 在装载集合变化后回调全部命令 spec overlay（宿主接命令总线；nil = 不接）。
+	OnCommands func(overlay []json.RawMessage) error
 }
 
 func New(st *store.Store, reg *tools.Registry, s *settings.Service, dir string) *Host {
@@ -75,8 +78,14 @@ func (h *Host) LoadDir() map[string]error {
 		}
 	}
 	overlay := h.collectIntentsLocked()
-	onIntents := h.OnIntents
+	cmdOverlay := h.collectCommandsLocked()
+	onIntents, onCommands := h.OnIntents, h.OnCommands
 	h.mu.Unlock()
+	if onCommands != nil {
+		if err := onCommands(cmdOverlay); err != nil {
+			results["<commands>"] = err
+		}
+	}
 	if onIntents != nil {
 		if err := onIntents(overlay); err != nil {
 			results["<intents>"] = err
@@ -170,6 +179,15 @@ func (h *Host) loadOne(dir string) error {
 		ld.Intents = append(ld.Intents, specs...)
 	}
 
+	// commands/*.json：Agent-Command spec overlay 形态透出（cmdbuf 注册；不在此校验语义）。
+	for _, name := range m.Provides.Commands {
+		var specs []json.RawMessage
+		if err := readAsset(dir, "commands", name, &specs); err != nil {
+			return fmt.Errorf("plugins: %s: commands %s: %w", m.ID, name, err)
+		}
+		ld.Commands = append(ld.Commands, specs...)
+	}
+
 	// prompts/*.md：画像模板（source=plugin，可被用户复制微调）。
 	for _, name := range m.Provides.Prompts {
 		content, err := os.ReadFile(filepath.Join(dir, "prompts", name+".md"))
@@ -194,9 +212,15 @@ func (h *Host) loadOne(dir string) error {
 	h.mu.Lock()
 	h.loaded[m.ID] = ld
 	overlay := h.collectIntentsLocked()
-	onIntents := h.OnIntents
+	cmdOverlay := h.collectCommandsLocked()
+	onIntents, onCommands := h.OnIntents, h.OnCommands
 	h.mu.Unlock()
 	_ = h.st.UpsertPlugin(m.ID, dir, m)
+	if onCommands != nil {
+		if err := onCommands(cmdOverlay); err != nil {
+			return fmt.Errorf("plugins: %s: commands rejected by command bus (kept previous): %w", m.ID, err)
+		}
+	}
 	if onIntents != nil {
 		if err := onIntents(overlay); err != nil {
 			return fmt.Errorf("plugins: %s: intents rejected by host gate (kept previous): %w", m.ID, err)
@@ -214,6 +238,15 @@ func (h *Host) collectIntentsLocked() []json.RawMessage {
 	return out
 }
 
+// collectCommandsLocked 汇总全部已装载插件的命令 overlay（调用方持锁）。
+func (h *Host) collectCommandsLocked() []json.RawMessage {
+	var out []json.RawMessage
+	for _, ld := range h.loaded {
+		out = append(out, ld.Commands...)
+	}
+	return out
+}
+
 // bindToolExecutor：声明式 HTTP 工具绑定执行器；纯描述型（无 http）工具暂不支持（代码插件为远期 sidecar 档）。
 func (h *Host) bindToolExecutor(desc core.ToolDesc) (tools.Executor, error) {
 	if desc.HTTP == nil {
diff --git a/internal/server/e2e_test.go b/internal/server/e2e_test.go
index a6b9723..e004afc 100644
--- a/internal/server/e2e_test.go
+++ b/internal/server/e2e_test.go
@@ -2,9 +2,13 @@ package server
 
 import (
 	"bufio"
-	"context"
 	"bytes"
+	"context"
 	"encoding/json"
+
+	agentcommand "agent-command"
+	"agent-system-backend/internal/cardsvc"
+	"agent-system-backend/internal/cmdbus"
 	"io"
 	"mime/multipart"
 	"net/http"
@@ -15,7 +19,6 @@ import (
 	"testing"
 	"time"
 
-	core "agent-system-core"
 	"agent-system-backend/internal/bus"
 	"agent-system-backend/internal/intentgate"
 	"agent-system-backend/internal/plugins"
@@ -25,6 +28,7 @@ import (
 	"agent-system-backend/internal/settings"
 	"agent-system-backend/internal/store"
 	"agent-system-backend/internal/tools"
+	core "agent-system-core"
 )
 
 // newTestServer 组合根（测试版）：mock runner 驱动全链路，不依赖模型。
@@ -49,6 +53,9 @@ func newTestServer(t *testing.T) (*Server, *store.Store) {
 	os.MkdirAll(pluginDir, 0o755)
 	ph := plugins.New(st, reg, setSvc, pluginDir)
 	srv := New(st, mgr, reg, profSvc, setSvc, ph)
+	srv.Cards = cardsvc.New(st, func(cid, runID string, ev core.StreamEventType, payload any) error { return nil })
+	srv.Bus = cmdbus.New(st, srv.Cards, nil)
+	srv.WireBuiltinCommands()
 	srv.Subscribe = func(cid string) (<-chan core.StreamEvent, func()) { return b.Subscribe(cid) }
 	return srv, st
 }
@@ -467,6 +474,83 @@ func TestCommandsRoute(t *testing.T) {
 	}
 }
 
+func TestDangerCommandConfirmFlowE2E(t *testing.T) {
+	srv, _ := newTestServer(t)
+	h := srv.Handler()
+	_, convID := setupConversation(t, h)
+
+	// 注册一条高危命令（模拟插件/扩展注册），API 入口 button 直发。
+	_ = srv.Bus.RegisterBuiltin(agentcommand.CommandSpec{
+		ID: "e2e.destroy", Title: "销毁演示", Danger: agentcommand.DangerHigh,
+		ParamsSchema: json.RawMessage(`{"type":"object","required":["what"],"properties":{"what":{"type":"string"}}}`),
+	}, "", func(ctx context.Context, req cmdbus.Request) (any, error) {
+		w, _ := req.Params["what"].(string)
+		return map[string]any{"destroyed": w}, nil
+	})
+
+	// 清单可见（数组契约，legacy {name,description} 兼容）：原始请求解码。
+	req := httptest.NewRequest("GET", "/api/commands", nil)
+	rec := httptest.NewRecorder()
+	h.ServeHTTP(rec, req)
+	if rec.Code != 200 {
+		t.Fatalf("list commands: %d", rec.Code)
+	}
+	var cl []map[string]any
+	if err := json.Unmarshal(rec.Body.Bytes(), &cl); err != nil {
+		t.Fatalf("list decode: %v", err)
+	}
+	found, legacySlash := false, false
+	for _, m := range cl {
+		if m["id"] == "e2e.destroy" && m["danger"] == "high" {
+			found = true
+		}
+		if m["name"] == "/help" {
+			legacySlash = true
+		}
+	}
+	if !found || !legacySlash {
+		t.Fatalf("listing wrong (found=%v legacy=%v): %v", found, legacySlash, cl)
+	}
+
+	// button 入口未确认 → 确认卡 + accepted 回执。
+	code, out := doJSON(t, h, "POST", "/api/commands/e2e.destroy", map[string]any{
+		"params": map[string]any{"what": "世界"}, "entrance": "button", "conversationId": convID})
+	if code != 200 {
+		t.Fatalf("dispatch: %d %v", code, out)
+	}
+	card, _ := out["card"].(map[string]any)
+	if card == nil {
+		t.Fatalf("confirm card missing: %v", out)
+	}
+	cardID, _ := card["id"].(string)
+
+	// 卡上确认 → 执行 committed + 审计可查。
+	code, out2 := doJSON(t, h, "POST", "/api/cards/"+cardID+"/actions/confirm", map[string]any{})
+	if code != 200 {
+		t.Fatalf("confirm action: %d %v", code, out2)
+	}
+	if rec, _ := out2["receipt"].(map[string]any); rec == nil || rec["state"] != "committed" {
+		t.Fatalf("confirm receipt: %v", out2)
+	}
+	code, audits := doJSON(t, h, "GET", "/api/commands/audit?conversationId="+convID, nil)
+	if code != 200 {
+		t.Fatalf("audit query: %d", code)
+	}
+	rows, _ := audits["audits"].([]any)
+	if len(rows) < 2 {
+		t.Fatalf("audit rows = %d, want >=2 (accepted+committed)", len(rows))
+	}
+	states := []string{}
+	for _, r := range rows {
+		m, _ := r.(map[string]any)
+		st, _ := m["state"].(string)
+		states = append(states, st)
+	}
+	if states[1] != "accepted" || states[0] != "committed" {
+		t.Fatalf("audit order wrong: %v (latest first)", states)
+	}
+}
+
 func TestStaticServed(t *testing.T) {
 	srv, _ := newTestServer(t)
 	h := srv.Handler()
@@ -641,10 +725,10 @@ func TestModelRoutingOverrideChain(t *testing.T) {
 	set(map[string]any{"runtime": map[string]any{"mock": false}}, "/api/settings/user")
 	prof := mustCode(t, h, "POST", "/api/profiles", map[string]any{
 		"id": "prof_route_c", "name": "路由C", "systemPrompt": "x",
-		"model": map[string]any{"chat": "model-C"},
-		"tools": map[string]any{"allow": []string{"*"}},
+		"model":   map[string]any{"chat": "model-C"},
+		"tools":   map[string]any{"allow": []string{"*"}},
 		"context": map[string]any{"maxHistoryMessages": 10},
-		"hitl": map[string]any{"askOnAmbiguity": true}, "budget": map[string]any{},
+		"hitl":    map[string]any{"askOnAmbiguity": true}, "budget": map[string]any{},
 	})
 	if prof["id"] != "prof_route_c" {
 		t.Fatalf("profile save: %v", prof)
diff --git a/internal/server/server.go b/internal/server/server.go
index e763afe..9510d9b 100644
--- a/internal/server/server.go
+++ b/internal/server/server.go
@@ -3,6 +3,7 @@
 package server
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -15,7 +16,9 @@ import (
 	"strings"
 	"time"
 
+	agentcommand "agent-command"
 	"agent-system-backend/internal/cardsvc"
+	"agent-system-backend/internal/cmdbus"
 	"agent-system-backend/internal/ingest"
 	"agent-system-backend/internal/plugins"
 	"agent-system-backend/internal/profiles"
@@ -37,6 +40,8 @@ type Server struct {
 	LimitLookup func() int           // 当前限流值（次/分；<=0 不限；组合根缓存注入）
 	mgr         *runmgr.Manager
 	Cards       *cardsvc.Service // 收件箱任务卡（nil = 不启用；组合根注入）
+	Bus         *cmdbus.Bus      // 命令总线（nil = 不启用；组合根注入；四入口同源 D27）
+	Gate        NLIntentGate     // 意图闸门（chat 入口同源判定；nil = 不接）
 	reg         *tools.Registry
 	prof        *profiles.Service
 	set         *settings.Service
@@ -54,6 +59,69 @@ func New(st *store.Store, mgr *runmgr.Manager, reg *tools.Registry, p *profiles.
 	return &Server{st: st, mgr: mgr, reg: reg, prof: p, set: s, plugins: ph, static: sub}
 }
 
+// NLIntentGate 意图闸门端口（intentgate.Gate 实现；避免包依赖方向反转）。
+type NLIntentGate interface {
+	Match(ctx context.Context, input string) (string, string)
+}
+
+// WireBuiltinCommands 注册内置命令（`/` 菜单全清单的数据源；处理器为宿主用例适配）。
+// 响应保持既有 {command, ...} 契约（frontend store.sendMessage 按此消费）。
+func (s *Server) WireBuiltinCommands() {
+	b := s.Bus
+	if b == nil {
+		return
+	}
+	must := func(err error) {
+		if err != nil {
+			panic("server: builtin command: " + err.Error()) // 装配期错误属编程错误
+		}
+	}
+	must(b.RegisterBuiltin(agentcommand.CommandSpec{ID: "builtin.help", Title: "帮助", Description: "查看可用命令与入口说明"},
+		"/help", func(ctx context.Context, req cmdbus.Request) (any, error) {
+			return map[string]any{"reply": fmt.Sprintf("可用命令（注册表 %d 条）——/new 新会话 · /mock on|off 演示模式 · /model <名称> 设置主模型 · /profile <id> 切换画像 · /help 帮助", len(b.List()))}, nil
+		}))
+	must(b.RegisterBuiltin(agentcommand.CommandSpec{ID: "conversation.create", Title: "新建会话", Description: "在当前项目下新建会话",
+		ParamsSchema: json.RawMessage(`{"type":"object","properties":{"title":{"type":"string"}}}`)},
+		"/new", func(ctx context.Context, req cmdbus.Request) (any, error) {
+			conv, err := s.st.GetConversation(req.Owner, req.ConversationID)
+			if err != nil {
+				return nil, err
+			}
+			c, err := s.st.CreateConversation(conv.Owner, conv.ProjectID, "新会话", conv.ProfileID)
+			if err != nil {
+				return nil, err
+			}
+			return map[string]any{"conversation": c}, nil
+		}))
+	must(b.RegisterBuiltin(agentcommand.CommandSpec{ID: "runtime.mock", Title: "演示模式", Description: "切换 mock 演示模式（on|off）",
+		ParamsSchema: json.RawMessage(`{"type":"object","required":["on"],"properties":{"on":{"type":"boolean"}}}`)},
+		"/mock", func(ctx context.Context, req cmdbus.Request) (any, error) {
+			on, _ := req.Params["on"].(bool)
+			if err := s.set.MergeUser(req.Owner, map[string]any{"runtime": map[string]any{"mock": on}}); err != nil {
+				return nil, err
+			}
+			return map[string]any{"runtime.mock": on}, nil
+		}))
+	must(b.RegisterBuiltin(agentcommand.CommandSpec{ID: "models.set", Title: "设置主模型", Description: "设置主模型名称",
+		ParamsSchema: json.RawMessage(`{"type":"object","required":["model"],"properties":{"model":{"type":"string"}}}`)},
+		"/model", func(ctx context.Context, req cmdbus.Request) (any, error) {
+			m, _ := req.Params["model"].(string)
+			if err := s.set.MergeUser(req.Owner, map[string]any{"models": map[string]any{"chat": map[string]any{"model": m}}}); err != nil {
+				return nil, err
+			}
+			return map[string]any{"model": m}, nil
+		}))
+	must(b.RegisterBuiltin(agentcommand.CommandSpec{ID: "conversation.profile", Title: "切换画像", Description: "切换会话画像",
+		ParamsSchema: json.RawMessage(`{"type":"object","required":["profileId"],"properties":{"profileId":{"type":"string"}}}`)},
+		"/profile", func(ctx context.Context, req cmdbus.Request) (any, error) {
+			pid, _ := req.Params["profileId"].(string)
+			if err := s.st.UpdateConversation(req.Owner, req.ConversationID, "", pid); err != nil {
+				return nil, err
+			}
+			return map[string]any{"profile": pid}, nil
+		}))
+}
+
 func (s *Server) Handler() http.Handler {
 	mux := http.NewServeMux()
 
@@ -110,6 +178,8 @@ func (s *Server) Handler() http.Handler {
 	mux.HandleFunc("GET /api/conversations/{id}/plan", s.getPlan)
 	mux.HandleFunc("GET /api/conversations/{id}/todos", s.getTodos)
 	mux.HandleFunc("GET /api/commands", s.listCommands)
+	mux.HandleFunc("POST /api/commands/{id}", s.execCommand)
+	mux.HandleFunc("GET /api/commands/audit", s.listAudits)
 	mux.HandleFunc("GET /api/parsers", s.listParsers)
 	mux.HandleFunc("POST /api/projects/{id}/knowledge", s.addKnowledge)
 	mux.HandleFunc("GET /api/knowledge/search", s.searchKnowledge)
@@ -397,42 +467,131 @@ func (s *Server) postMessage(w http.ResponseWriter, r *http.Request) {
 		writeStoreErr(w, err)
 		return
 	}
+	// chat 入口同源（D27）：意图闸门命中且命令总线承接 → 统一分发（同审计），不起 run。
+	if s.Bus != nil && s.Gate != nil && !strings.HasPrefix(text, "/") {
+		if branch, topID := s.Gate.Match(r.Context(), text); branch == "matched" && s.Bus.HasCommand(topID) {
+			resp := s.Bus.Dispatch(r.Context(), cmdbus.Request{
+				ID: topID, Params: map[string]any{"text": text}, Entrance: "chat", Actor: owner,
+				Owner: owner, ConversationID: convID, AnchorMessageID: msg.ID,
+			})
+			out := map[string]any{"message": msg, "receipt": resp.Receipt, "command": topID}
+			if resp.Card != nil {
+				out["card"] = resp.Card
+			}
+			if m, ok := resp.Payload.(map[string]any); ok {
+				for k, v := range m {
+					out[k] = v
+				}
+			}
+			writeJSON(w, http.StatusOK, out)
+			return
+		}
+	}
 	run, err := s.mgr.StartConversationRun(conv, msg, parsedDocs)
 	writeJSONOr(w, map[string]any{"message": msg, "run": run}, err)
 }
 
-// handleCommand 内置命令（注册表数据驱动，插件可扩展 commands 后补）。
+// handleCommand `/` 入口 → 命令总线（D27 四入口同源；slash 语义解析后统一分发+审计）。
 func (s *Server) handleCommand(w http.ResponseWriter, r *http.Request, conv core.Conversation, text string) {
 	fields := strings.Fields(text)
-	cmd := strings.ToLower(fields[0])
-	switch cmd {
-	case "/help":
-		writeJSON(w, http.StatusOK, map[string]any{"command": cmd, "reply": "可用命令：/new 新会话 · /mock on|off 演示模式 · /model <名称> 设置主模型 · /profile <id> 切换画像 · /help 帮助"})
-	case "/new":
-		c, err := s.st.CreateConversation(conv.Owner, conv.ProjectID, "新会话", conv.ProfileID)
-		writeJSONOr(w, map[string]any{"command": cmd, "conversation": c}, err)
-	case "/mock":
-		if len(fields) < 2 || (fields[1] != "on" && fields[1] != "off") {
-			http.Error(w, "usage: /mock on|off", http.StatusBadRequest)
-			return
-		}
-		val := fields[1] == "on"
-		writeJSONOr(w, map[string]any{"command": cmd, "runtime.mock": val}, s.set.MergeUser(conv.Owner, map[string]any{"runtime": map[string]any{"mock": val}}))
-	case "/model":
-		if len(fields) < 2 {
-			http.Error(w, "usage: /model <model-name>", http.StatusBadRequest)
-			return
-		}
-		writeJSONOr(w, map[string]any{"command": cmd, "model": fields[1]}, s.set.MergeUser(conv.Owner, map[string]any{"models": map[string]any{"chat": map[string]any{"model": fields[1]}}}))
-	case "/profile":
-		if len(fields) < 2 {
-			http.Error(w, "usage: /profile <id>", http.StatusBadRequest)
-			return
-		}
-		writeJSONOr(w, map[string]any{"command": cmd, "profile": fields[1]}, s.st.UpdateConversation(conv.Owner, conv.ID, "", fields[1]))
-	default:
-		http.Error(w, "未知命令 "+cmd+"（/help 查看）", http.StatusBadRequest)
+	slash := strings.ToLower(fields[0])
+	if s.Bus == nil {
+		http.Error(w, "commands disabled", http.StatusServiceUnavailable)
+		return
 	}
+	id, ok := s.Bus.ResolveSlash(slash)
+	if !ok {
+		http.Error(w, "未知命令 "+slash+"（/help 查看）", http.StatusBadRequest)
+		return
+	}
+	params, err := parseSlashParams(id, fields[1:])
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+	resp := s.Bus.Dispatch(r.Context(), cmdbus.Request{
+		ID: id, Params: params, Entrance: "slash", Actor: s.owner(r),
+		Owner: s.owner(r), ConversationID: conv.ID,
+	})
+	out := map[string]any{"command": slash, "receipt": resp.Receipt}
+	if m, ok := resp.Payload.(map[string]any); ok {
+		for k, v := range m {
+			out[k] = v
+		}
+	}
+	if resp.Receipt.State == agentcommand.StateRejected {
+		out["error"] = resp.Receipt.Reason
+	}
+	writeJSON(w, http.StatusOK, out)
+}
+
+// parseSlashParams slash 参数 → 命令参数（按命令语义；未知参数原样透传由 schema 校验拒绝）。
+func parseSlashParams(id string, args []string) (map[string]any, error) {
+	switch id {
+	case "runtime.mock":
+		if len(args) != 1 || (args[0] != "on" && args[0] != "off") {
+			return nil, errors.New("usage: /mock on|off")
+		}
+		return map[string]any{"on": args[0] == "on"}, nil
+	case "models.set":
+		if len(args) < 1 {
+			return nil, errors.New("usage: /model <model-name>")
+		}
+		return map[string]any{"model": strings.Join(args, " ")}, nil
+	case "conversation.profile":
+		if len(args) < 1 {
+			return nil, errors.New("usage: /profile <id>")
+		}
+		return map[string]any{"profileId": args[0]}, nil
+	case "conversation.create":
+		if len(args) > 0 {
+			return map[string]any{"title": strings.Join(args, " ")}, nil
+		}
+		return map[string]any{}, nil
+	default:
+		return map[string]any{}, nil
+	}
+}
+
+// execCommand 通用命令入口（button/card/chat 等 API 客户端统一走此路由；D27）。
+func (s *Server) execCommand(w http.ResponseWriter, r *http.Request) {
+	if s.Bus == nil {
+		http.Error(w, "commands disabled", http.StatusServiceUnavailable)
+		return
+	}
+	var body struct {
+		Params          map[string]any `json:"params"`
+		Entrance        string         `json:"entrance"`
+		ConversationID  string         `json:"conversationId"`
+		AnchorMessageID string         `json:"anchorMessageId"`
+	}
+	_ = json.NewDecoder(r.Body).Decode(&body)
+	if body.Params == nil {
+		body.Params = map[string]any{}
+	}
+	resp := s.Bus.Dispatch(r.Context(), cmdbus.Request{
+		ID: r.PathValue("id"), Params: body.Params, Entrance: body.Entrance, Actor: s.owner(r),
+		Owner: s.owner(r), ConversationID: body.ConversationID, AnchorMessageID: body.AnchorMessageID,
+	})
+	code := http.StatusOK
+	if resp.Receipt.State == agentcommand.StateRejected {
+		code = http.StatusBadRequest
+	}
+	out := map[string]any{"receipt": resp.Receipt}
+	if resp.Payload != nil {
+		out["payload"] = resp.Payload
+	}
+	if resp.Card != nil {
+		out["card"] = resp.Card
+	}
+	writeJSON(w, code, out)
+}
+
+// listAudits 审计查询（会话维度或全局；入口对称的可核查凭证）。
+func (s *Server) listAudits(w http.ResponseWriter, r *http.Request) {
+	limit, _ := strconv.Atoi(r.URL.Query().Get("limit"))
+	audits, err := s.st.ListAudits(r.URL.Query().Get("conversationId"), limit)
+	writeJSONOr(w, map[string]any{"audits": audits}, err)
 }
 
 func (s *Server) cancelRun(w http.ResponseWriter, r *http.Request) {
@@ -485,6 +644,14 @@ func (s *Server) cardAction(w http.ResponseWriter, r *http.Request) {
 		FreeText string `json:"freeText,omitempty"`
 	}
 	_ = json.NewDecoder(r.Body).Decode(&body)
+	// 命令确认卡（ref=cmd:<id>）走总线回道：confirm=执行挂起命令，其余=取消。
+	if ref, err := s.st.CardRef(owner, r.PathValue("id")); err == nil && strings.HasPrefix(ref, "cmd:") {
+		if card, err := s.Cards.Get(owner, r.PathValue("id")); err == nil && card.Status == core.CardActionRequired {
+			resp := s.Bus.Confirm(owner, card.ID, r.PathValue("actionId"))
+			writeJSON(w, http.StatusOK, map[string]any{"card": card, "receipt": resp.Receipt, "payload": resp.Payload})
+			return
+		}
+	}
 	card, label, err := s.Cards.Action(owner, r.PathValue("id"), r.PathValue("actionId"), body.FreeText)
 	if err != nil {
 		writeStoreErr(w, err)
@@ -812,17 +979,25 @@ func (s *Server) getTodos(w http.ResponseWriter, r *http.Request) {
 	writeJSONOr(w, l, err)
 }
 
-var builtinCommands = []map[string]string{
-	{"name": "/help", "description": "查看可用命令"},
-	{"name": "/new", "description": "新建会话"},
-	{"name": "/mock", "description": "演示模式 on|off（不调用真实模型）"},
-	{"name": "/model", "description": "设置主模型名称"},
-	{"name": "/profile", "description": "切换会话画像"},
+func (s *Server) listCommands(w http.ResponseWriter, r *http.Request) {
+	out := []map[string]any{}
+	if s.Bus != nil {
+		slashOf := map[string]string{}
+		for slash, id := range s.Bus.SlashTable() {
+			slashOf[id] = slash
+		}
+		for _, c := range s.Bus.List() {
+			item := map[string]any{"id": c.Spec.ID, "title": c.Spec.Title, "description": c.Spec.Description, "danger": string(c.Spec.Danger), "source": string(c.Source), "enabled": c.Enabled}
+			if slash, ok := slashOf[c.Spec.ID]; ok {
+				item["name"] = slash // legacy 兼容：`/` 菜单按 name 消费
+			}
+			out = append(out, item)
+		}
+	}
+	writeJSON(w, http.StatusOK, out)
 }
 
-func (s *Server) listCommands(w http.ResponseWriter, r *http.Request) {
-	writeJSON(w, http.StatusOK, builtinCommands)
-}
+
 
 func (s *Server) listParsers(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusOK, ingest.ParsersDescription())
diff --git a/internal/store/audit.go b/internal/store/audit.go
new file mode 100644
index 0000000..1bff805
--- /dev/null
+++ b/internal/store/audit.go
@@ -0,0 +1,55 @@
+package store
+
+import (
+	"database/sql"
+	"encoding/json"
+	"time"
+
+	agentcommand "agent-command"
+)
+
+// AppendAudit 追加命令审计信封（cmdbus 端口；v7 command_audit）。
+func (s *Store) AppendAudit(env agentcommand.AuditEnvelope) error {
+	raw, err := json.Marshal(env)
+	if err != nil {
+		return err
+	}
+	_, err = s.db.Exec(s.q(`INSERT INTO command_audit (time, command_id, source, entrance, state, operation_id, conversation_id, payload)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?)`),
+		env.Time.UTC().Format(time.RFC3339Nano), env.CommandID, string(env.Source), env.Entrance, string(env.State),
+		env.OperationID, env.ConversationID, string(raw))
+	return err
+}
+
+// ListAudits 审计查询（时间倒序；conversationID 空 = 全局）。
+func (s *Store) ListAudits(conversationID string, limit int) ([]agentcommand.AuditEnvelope, error) {
+	if limit <= 0 || limit > 500 {
+		limit = 100
+	}
+	var (
+		rows *sql.Rows
+		err  error
+	)
+	if conversationID == "" {
+		rows, err = s.db.Query(s.q(`SELECT payload FROM command_audit ORDER BY time DESC LIMIT ?`), limit)
+	} else {
+		rows, err = s.db.Query(s.q(`SELECT payload FROM command_audit WHERE conversation_id=? ORDER BY time DESC LIMIT ?`), conversationID, limit)
+	}
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	out := []agentcommand.AuditEnvelope{}
+	for rows.Next() {
+		var raw string
+		if err := rows.Scan(&raw); err != nil {
+			return nil, err
+		}
+		var env agentcommand.AuditEnvelope
+		if err := json.Unmarshal([]byte(raw), &env); err != nil {
+			return nil, err
+		}
+		out = append(out, env)
+	}
+	return out, rows.Err()
+}
diff --git a/internal/store/cards.go b/internal/store/cards.go
index e6eae5e..274242a 100644
--- a/internal/store/cards.go
+++ b/internal/store/cards.go
@@ -66,6 +66,16 @@ func (s *Store) ListCards(owner, conversationID string) ([]core.ActivityCard, er
 	return out, rows.Err()
 }
 
+// CardRef 取卡的 ref 列（命令确认卡回道判定："cmd:<id>" 前缀）。
+func (s *Store) CardRef(owner, id string) (string, error) {
+	row := s.db.QueryRow(s.q(`SELECT ref FROM activity_cards WHERE id=? AND owner=?`), id, owner)
+	var ref string
+	if err := row.Scan(&ref); err != nil {
+		return "", err
+	}
+	return ref, nil
+}
+
 // CardIDByRef 按引用取卡 ID（HITL 投影联动："hitl:<id>"；最新一条）。
 func (s *Store) CardIDByRef(owner, ref string) (string, error) {
 	row := s.db.QueryRow(s.q(`SELECT id FROM activity_cards WHERE ref=? AND owner=? ORDER BY updated_at DESC LIMIT 1`), ref, owner)
diff --git a/internal/store/migrate.go b/internal/store/migrate.go
index 383db3f..f702db2 100644
--- a/internal/store/migrate.go
+++ b/internal/store/migrate.go
@@ -215,6 +215,19 @@ func init() {
 				`CREATE INDEX IF NOT EXISTS idx_cards_ref ON activity_cards(ref)`,
 			}},
 			down: map[string][]string{"sqlite": {`DROP TABLE IF EXISTS activity_cards`}, "postgres": {`DROP TABLE IF EXISTS activity_cards`}}},
+		migration{version: 7, name: "command_audit",
+			// 命令总线审计（agent-command.AuditEnvelope）：payload 存整信封 JSON；
+			// 冗余列支持按会话/状态/操作号检索（提案 T3，四入口同源审计）。
+			up: map[string][]string{"sqlite": {
+				`CREATE TABLE IF NOT EXISTS command_audit (id INTEGER PRIMARY KEY AUTOINCREMENT, time TEXT NOT NULL, command_id TEXT NOT NULL, source TEXT NOT NULL DEFAULT '', entrance TEXT NOT NULL DEFAULT '', state TEXT NOT NULL, operation_id TEXT NOT NULL DEFAULT '', conversation_id TEXT NOT NULL DEFAULT '', payload TEXT NOT NULL)`,
+				`CREATE INDEX IF NOT EXISTS idx_audit_conv ON command_audit(conversation_id, time)`,
+				`CREATE INDEX IF NOT EXISTS idx_audit_op ON command_audit(operation_id)`,
+			}, "postgres": {
+				`CREATE TABLE IF NOT EXISTS command_audit (id SERIAL PRIMARY KEY, time TEXT NOT NULL, command_id TEXT NOT NULL, source TEXT NOT NULL DEFAULT '', entrance TEXT NOT NULL DEFAULT '', state TEXT NOT NULL, operation_id TEXT NOT NULL DEFAULT '', conversation_id TEXT NOT NULL DEFAULT '', payload TEXT NOT NULL)`,
+				`CREATE INDEX IF NOT EXISTS idx_audit_conv ON command_audit(conversation_id, time)`,
+				`CREATE INDEX IF NOT EXISTS idx_audit_op ON command_audit(operation_id)`,
+			}},
+			down: map[string][]string{"sqlite": {`DROP TABLE IF EXISTS command_audit`}, "postgres": {`DROP TABLE IF EXISTS command_audit`}}},
 	)
 }
 
diff --git a/internal/store/store_test.go b/internal/store/store_test.go
index 1ebf07d..b80abc3 100644
--- a/internal/store/store_test.go
+++ b/internal/store/store_test.go
@@ -56,8 +56,8 @@ func TestMigrationUpgradesExistingDatabase(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if len(got) != 6 {
-		t.Fatalf("expected versions [1..6], got %v", got)
+	if len(got) != 7 {
+		t.Fatalf("expected versions [1..7], got %v", got)
 	}
 	// 老库形态（v2 前）：events 全局自增、settings 单列主键。
 	if err := st.MigrateDown(1); err != nil {
diff --git a/policy/modules/cardsvc.md b/policy/modules/cardsvc.md
new file mode 100644
index 0000000..35f31cb
--- /dev/null
+++ b/policy/modules/cardsvc.md
@@ -0,0 +1,8 @@
+# 模块卡：internal/cardsvc（收件箱任务卡）
+
+- 状态：active（T2 落地，提案 D25/D33）
+- 职责：ActivityCard 生命周期（创建/更新/状态机/pin/dismiss/动作+回执/ref 幂等消解）、存储（store v6 activity_cards）、card.* 事件经会话事件管道发布（persist/seq/replay）、摄取/编排/HITL 投影卡 producer 供运行时与摄取侧调用。
+- 公开面：`New(st, emit)`、`Create/Get/List/Update/SetStatus/SetPinned/Dismiss/Action/ResolveByRef`。
+- 依赖：core（ActivityCard）、store（自有表）；被 runmgr/server/ingest/squadadapter 消费；cmdbus 的确认卡经 CardPort 消费。
+- 隔离档位：L1 包（仓内）；有自有存储（activity_cards 表），事件发布为注入端口。
+- 升级拆仓触发条件：跨会话项目级收件箱（v1 边界外）或第二宿主出现时，连同 cmdbus 的确认卡语义一并评估。
diff --git a/policy/modules/cmdbus.md b/policy/modules/cmdbus.md
new file mode 100644
index 0000000..adbf761
--- /dev/null
+++ b/policy/modules/cmdbus.md
@@ -0,0 +1,9 @@
+# 模块卡：internal/cmdbuf（命令总线）
+
+- 状态：active（T3 落地，提案 D27/D30/D33）
+- 职责：组合 Agent-Command 生态库——命令注册（builtin/plugin/user）、四入口同源分发（button/card/slash/chat→api 归一）、params JSON-Schema 子集校验、危险命令（danger=high）的内联确认卡收口、审计信封落盘（四态回执）。
+- 公开面：`New(AuditStore, CardPort, now)`、`RegisterBuiltin/RegisterPluginCommands`、`Dispatch(ctx, Request) Response`、`Confirm(owner, cardID, actionID)`、`ResolveSlash/SlashTable/HasCommand/List`。
+- 依赖：agent-command（生态库，嵌套 submodule + replace）；core（ActivityCard/UIAction）；不依赖 server/runmgr（server 依赖它；端口注入避免反向依赖）。
+- 隔离档位：L1 包（仓内）；纯编排无自有存储——审计走 store 端口、确认卡走 cardsvc 端口。
+- 已知限制：确认挂起态为进程内（重启后确认返回 rejected expired）；params 校验为 draft-07 标量子集。
+- 升级拆仓触发条件：出现第二宿主（非 backend）需要同一命令总线时，随 Agent-Command 生态位评估拆出（同 cardsvc 判据）。