diff --git a/src/components/ArtifactsPanel.tsx b/src/components/ArtifactsPanel.tsx
new file mode 100644
index 0000000..c830b17
--- /dev/null
+++ b/src/components/ArtifactsPanel.tsx
@@ -0,0 +1,67 @@
+// 工件面板（工作区文件管理）：搜索 + kind 过滤 + 上传；行内深预览/右栏预览/下载。
+// ⌘1 弹层与右栏「文件」页签共用这一份。删除仍是保留能力，系统默认不提供入口。
+import { useState } from 'react'
+import { store, useStore } from '../store'
+import { api } from '../api'
+import { Icon } from '@ui'
+import { artifactIcon, humanSize } from '../messageparts'
+
+export function ArtifactsPanel() {
+  const artifacts = useStore(s => s.artifacts)
+  const [q, setQ] = useState('')
+  const [kind, setKind] = useState<'all' | 'document' | 'data' | 'image'>('all')
+
+  const kinds = ['all', 'document', 'data', 'image'] as const
+  const visible = artifacts.filter(a =>
+    (kind === 'all' || a.kind === kind) && a.name.toLowerCase().includes(q.toLowerCase()))
+
+  return (
+    <div className="artifacts-panel">
+      <div className="ap-toolbar">
+        <input className="search-input" placeholder="搜索文件名…" value={q} onChange={e => setQ(e.target.value)} />
+        {kinds.map(k => (
+          <button key={k} className={`kind-pill ${kind === k ? 'on' : ''}`} onClick={() => setKind(k)}>
+            {k === 'all' ? '全部' : k === 'document' ? '文档' : k === 'data' ? '数据' : '图片'}
+          </button>
+        ))}
+        <label className="btn ghost ap-upload" title="上传文件到当前项目">
+          <Icon name="paperclip" size={14} /> 上传
+          <input type="file" multiple style={{ display: 'none' }} onChange={async e => {
+            for (const f of Array.from(e.target.files ?? [])) await store.uploadAttachment(f)
+            e.target.value = ''
+          }} />
+        </label>
+      </div>
+      {artifacts.length === 0
+        ? <div className="empty-note">暂无文件——上传附件或让模型产出文档（mock：#doc）；这里可浏览、预览、下载</div>
+        : visible.length === 0
+          ? <div className="empty-note">没有匹配「{q}」的文件</div>
+          : visible.map(a => (
+            // 预览落位在右栏——弹层必须先收起，否则预览换到被盖住的右栏。
+            <div key={a.id} className="artifact-row" data-artifact-row={a.id}
+              onClick={() => { store.closeWorkspace(); store.requestPreview(a) }} title={`预览 ${a.name}（右栏，边聊边看）`}>
+              <span className="ar-icon"><Icon name={artifactIcon(a.name, a.kind)} size={15} /></span>
+              <span className="ar-main">
+                <span className="name">{a.name}</span>
+                <span className="meta">{a.kind} · {humanSize(a.size) || '—'} · {shortTime(a.updatedAt)}</span>
+              </span>
+              <span className="ar-acts">
+                <button className="icon-btn" title="全屏预览" onClick={e => { e.stopPropagation(); store.closeWorkspace(); store.requestPreview(a, 'full') }}><Icon name="eye" size={14} /></button>
+                <a className="icon-btn" title="下载" href={api.artifactDownloadUrl(a.id)} download={a.name}
+                  onClick={e => e.stopPropagation()}><Icon name="download" size={14} /></a>
+              </span>
+            </div>
+          ))}
+    </div>
+  )
+}
+
+function shortTime(iso: string): string {
+  try {
+    const d = new Date(iso)
+    const now = new Date()
+    return d.toDateString() === now.toDateString()
+      ? d.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' })
+      : d.toLocaleDateString([], { month: '2-digit', day: '2-digit' })
+  } catch { return '' }
+}
diff --git a/src/components/Conversation.tsx b/src/components/Conversation.tsx
index 77e5075..85659f6 100644
--- a/src/components/Conversation.tsx
+++ b/src/components/Conversation.tsx
@@ -318,6 +318,40 @@ function CommandMenu({ text, onPick }: { text: string; onPick: (cmd: string) =>
   )
 }
 
+function OutboxPanel() {
+  const outbox = useStore(s => s.outbox)
+  const [editing, setEditing] = useState<string | null>(null)
+  const [draft, setDraft] = useState('')
+  if (outbox.length === 0) return null
+  return (
+    <Collapsible id="composer-outbox" defaultOpen
+      trigger={<span>排队 {outbox.length}</span>}
+      triggerClassName="outbox-trigger">
+      <ul className="outbox-list">
+        {outbox.map(item => (
+          <li key={item.id} className="outbox-item">
+            {editing === item.id ? (
+              <input className="search-input outbox-edit" value={draft} onChange={e => setDraft(e.target.value)}
+                onKeyDown={e => {
+                  if (e.key === 'Enter') { store.updateOutbox(item.id, draft); setEditing(null) }
+                }} />
+            ) : (
+              <span className="outbox-text" title={item.text}>{item.text.trim() || '（仅附件）'}{item.attachmentNames.length > 0 ? ` · ${item.attachmentNames.join('、')}` : ''}</span>
+            )}
+            {editing === item.id ? (
+              <button className="btn ghost" onClick={() => { store.updateOutbox(item.id, draft); setEditing(null) }}>保存</button>
+            ) : (
+              <button className="btn ghost" onClick={() => { setEditing(item.id); setDraft(item.text) }}>修改</button>
+            )}
+            <button className="btn ghost" onClick={() => store.sendOutboxNow(item.id)}>发送</button>
+            <button className="icon-btn" title="移出队列" onClick={() => store.removeOutbox(item.id)}><Icon name="x" size={12} /></button>
+          </li>
+        ))}
+      </ul>
+    </Collapsible>
+  )
+}
+
 export function Conversation() {
   const currentConvId = useStore(s => s.currentConvId)
   const conversation = useStore(s => s.tasks.find(c => c.id === s.currentConvId))
@@ -349,8 +383,14 @@ export function Conversation() {
   const send = async () => {
     if (!text.trim() && attachmentIds.length === 0) return
     const t = text
+    const ids = attachmentIds
+    const names = attachmentNames
     setText(''); setAttachmentIds([]); setAttachmentNames([])
-    await store.sendMessage(t, attachmentIds)
+    if (active) {
+      store.enqueueOutbox(t, ids, names)
+      return
+    }
+    await store.sendMessage(t, ids)
   }
 
   if (!currentConvId) {
@@ -431,6 +471,7 @@ export function Conversation() {
       </div>
 
       <div className="input-bar">
+        <OutboxPanel />
         {attachmentNames.length > 0 && (
           <div className="attachments">
             {attachmentNames.map((n, i) => <span className="attach-chip" key={i}><Icon name='paperclip' size={12} /> {n}
@@ -450,15 +491,14 @@ export function Conversation() {
             }} />
           </label>
           <textarea rows={1} value={text} placeholder={hasOpenConfirm(cards) ? '有待确认的命令——请先处理上方确认卡'
-            : active ? '回合进行中——等当前回合结束（或点「停止」）后再发送'
+            : active ? '继续输入以排队'
             : artifacts.length > 0 ? '输入消息…（/ 命令，@knowledge 检索注入）' : '输入消息…（/ 命令）'}
             onChange={e => setText(e.target.value)}
             onKeyDown={e => { if (e.key === 'Enter' && !e.shiftKey) { e.preventDefault(); send() } }} />
-          {active ? (
+          {active && (
             <button className="btn danger" onClick={() => store.cancelActive()}>停止</button>
-          ) : (
-            <button className="btn" onClick={send} disabled={!text.trim() && attachmentIds.length === 0}>发送</button>
           )}
+          <button className="btn" onClick={send} disabled={!text.trim() && attachmentIds.length === 0}>{active ? '排队' : '发送'}</button>
         </div>
       </div>
     </div>
diff --git a/src/components/Workbench.tsx b/src/components/Workbench.tsx
index c1bdfe9..e9172c4 100644
--- a/src/components/Workbench.tsx
+++ b/src/components/Workbench.tsx
@@ -5,6 +5,7 @@ import type { Run } from '../contracts'
 import { InboxList, pendingCount, FilePreview, type ActivityCard, type DocBridge } from '@ui'
 import { Icon } from '@ui'
 import { api } from '../api'
+import { ArtifactsPanel } from './ArtifactsPanel'
 
 // 工件解析/打开注入：渲染器纯展示，doc-ref 词汇经此桥接本仓状态（D29）。
 // 打开语义走 requestPreview 唯一入口（阶段③ 收敛：默认右栏轻预览）。
@@ -59,11 +60,14 @@ export function Workbench() {
   const railArtifact = useStore(s => (railId ? s.artifacts.find(a => a.id === railId) : undefined))
 
   const showPreview = rightTab === 'preview'
+  const showFiles = rightTab === 'files'
   return (
     <>
       <div className="tabs">
-        <button className={`tab ${!showPreview ? 'active' : ''}`} onClick={() => store.setUI({ rightTab: 'inbox' })}
+        <button className={`tab ${!showPreview && !showFiles ? 'active' : ''}`} onClick={() => store.setUI({ rightTab: 'inbox' })}
           title="收件箱">收件箱{pending > 0 ? ` ${pending}` : ''}</button>
+        <button className={`tab ${showFiles ? 'active' : ''}`} onClick={() => store.setUI({ rightTab: 'files', rightCollapsed: false })}
+          title="文件（与 ⌘1 工件面板同一份列表）">文件</button>
         <button className={`tab ${showPreview ? 'active' : ''}`} onClick={() => store.railPreview(railArtifact ?? null)}
           title="预览（右栏轻预览）"><Icon name="eye" size={13} /> 预览</button>
         <span className="spacer" style={{ flex: 1 }} />
@@ -92,6 +96,10 @@ export function Workbench() {
             </>
           ) : <div className="empty-note" style={{ padding: 14 }}>点消息里的工件卡片或右侧工件面板——文件会在这里边聊边看（md/图片/pdf/Office/代码均可）</div>}
         </div>
+      ) : showFiles ? (
+        <div className="tab-body">
+          <ArtifactsPanel />
+        </div>
       ) : (
         <div className="tab-body">
           <CurrentTaskCard plan={plan} todos={todos} />
diff --git a/src/components/Workspaces.tsx b/src/components/Workspaces.tsx
index 6798c25..2d85ee7 100644
--- a/src/components/Workspaces.tsx
+++ b/src/components/Workspaces.tsx
@@ -1,14 +1,12 @@
 // 工作区弹层（提案 T4/D25）：工件/代理 经 OverlayHost 呈现。
 // 重设计方案 阶段②（IA 对话优先）：插件面板/服务端声明工作区属系统能力，
 // 只进「系统管理」分区（AdminZone），不占普通用户的 ⌘1–9；清单按角色收窄。
-import { useState } from 'react'
 import { store, useStore } from '../store'
 import type { Run } from '../contracts'
-import { api } from '../api'
-import { OverlayHost, Icon, type DocBridge } from '@ui'
+import { OverlayHost, type DocBridge } from '@ui'
 import { docBridge } from './Workbench'
 import { AgentRow } from './Workbench'
-import { artifactIcon, humanSize } from '../messageparts'
+import { ArtifactsPanel } from './ArtifactsPanel'
 
 /** 工作区清单（顺序即 ⌘ 序号）：内置在前，插件面板/声明工作区仅管理员可见。 */
 export function workspaceEntries(): { key: string; title: string; icon: string; shortcut: string }[] {
@@ -59,70 +57,6 @@ export function Workspaces() {
   return null
 }
 
-/** 工件面板（工作区文件管理）：搜索 + kind 过滤 + 上传；行内 深预览/右栏预览/下载。
- *  删除是保留能力：DELETE /api/artifacts/{id} 与 api.deleteArtifact 均在（插件可用），
- *  系统默认不提供删除入口（提案 2026-09-30-file-preview-and-reserved-capabilities §2.2）。 */
-export function ArtifactsPanel() {
-  const artifacts = useStore(s => s.artifacts)
-  const [q, setQ] = useState('')
-  const [kind, setKind] = useState<'all' | 'document' | 'data' | 'image'>('all')
-
-  const kinds = ['all', 'document', 'data', 'image'] as const
-  const visible = artifacts.filter(a =>
-    (kind === 'all' || a.kind === kind) && a.name.toLowerCase().includes(q.toLowerCase()))
-
-  return (
-    <div className="artifacts-panel">
-      <div className="ap-toolbar">
-        <input className="search-input" placeholder="搜索文件名…" value={q} onChange={e => setQ(e.target.value)} />
-        {kinds.map(k => (
-          <button key={k} className={`kind-pill ${kind === k ? 'on' : ''}`} onClick={() => setKind(k)}>
-            {k === 'all' ? '全部' : k === 'document' ? '文档' : k === 'data' ? '数据' : '图片'}
-          </button>
-        ))}
-        <label className="btn ghost ap-upload" title="上传文件到当前项目">
-          <Icon name="paperclip" size={14} /> 上传
-          <input type="file" multiple style={{ display: 'none' }} onChange={async e => {
-            for (const f of Array.from(e.target.files ?? [])) await store.uploadAttachment(f)
-            e.target.value = ''
-          }} />
-        </label>
-      </div>
-      {artifacts.length === 0
-        ? <div className="empty-note">暂无文件——上传附件或让模型产出文档（mock：#doc）；这里可浏览、预览、下载</div>
-        : visible.length === 0
-          ? <div className="empty-note">没有匹配「{q}」的文件</div>
-          : visible.map(a => (
-            // 预览落位在右栏——弹层必须先收起，否则预览换到被盖住的右栏，
-            // 用户看到的是「点了没反应」（工件面板是全屏 OverlayHost）。
-            <div key={a.id} className="artifact-row" data-artifact-row={a.id}
-              onClick={() => { store.closeWorkspace(); store.requestPreview(a) }} title={`预览 ${a.name}（右栏，边聊边看）`}>
-              <span className="ar-icon"><Icon name={artifactIcon(a.name, a.kind)} size={15} /></span>
-              <span className="ar-main">
-                <span className="name">{a.name}</span>
-                <span className="meta">{a.kind} · {humanSize(a.size) || '—'} · {shortTime(a.updatedAt)}</span>
-              </span>
-              <span className="ar-acts">
-                <button className="icon-btn" title="全屏预览" onClick={e => { e.stopPropagation(); store.closeWorkspace(); store.requestPreview(a, 'full') }}><Icon name="eye" size={14} /></button>
-                <a className="icon-btn" title="下载" href={api.artifactDownloadUrl(a.id)} download={a.name}
-                  onClick={e => e.stopPropagation()}><Icon name="download" size={14} /></a>
-              </span>
-            </div>
-          ))}
-    </div>
-  )
-}
-
-function shortTime(iso: string): string {
-  try {
-    const d = new Date(iso)
-    const now = new Date()
-    return d.toDateString() === now.toDateString()
-      ? d.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' })
-      : d.toLocaleDateString([], { month: '2-digit', day: '2-digit' })
-  } catch { return '' }
-}
-
 /** 代理面板（任务树；点击进 AgentTracker 深读）。 */
 export function AgentsPanel({ runs }: { runs: Run[] }) {
   if (runs.length === 0) return <div className="empty-note">暂无运行——多代理任务会在此形成任务树（mock：#agents）</div>
diff --git a/src/outbox.ts b/src/outbox.ts
new file mode 100644
index 0000000..f51a42a
--- /dev/null
+++ b/src/outbox.ts
@@ -0,0 +1,38 @@
+// 输入排队（纯数据）：回合进行中先入本地队列，终态再逐条发送。
+export interface QueuedMessage {
+  id: string
+  text: string
+  attachmentIds: string[]
+  attachmentNames: string[]
+}
+
+export function newQueuedMessage(text: string, attachmentIds: string[], attachmentNames: string[]): QueuedMessage {
+  return {
+    id: `${Date.now().toString(36)}-${Math.random().toString(36).slice(2, 8)}`,
+    text,
+    attachmentIds,
+    attachmentNames,
+  }
+}
+
+export function enqueueMessage(queue: QueuedMessage[], item: QueuedMessage): QueuedMessage[] {
+  return [...queue, item]
+}
+
+export function enqueueMessageFront(queue: QueuedMessage[], item: QueuedMessage): QueuedMessage[] {
+  return [item, ...queue.filter(q => q.id !== item.id)]
+}
+
+export function removeQueuedMessage(queue: QueuedMessage[], id: string): QueuedMessage[] {
+  return queue.filter(q => q.id !== id)
+}
+
+export function replaceQueuedText(queue: QueuedMessage[], id: string, text: string): QueuedMessage[] {
+  return queue.map(q => q.id === id ? { ...q, text } : q)
+}
+
+export function promoteQueuedMessage(queue: QueuedMessage[], id: string): QueuedMessage[] {
+  const item = queue.find(q => q.id === id)
+  if (!item) return queue
+  return enqueueMessageFront(queue, item)
+}
diff --git a/src/store.ts b/src/store.ts
index ecb04a5..fd1b45d 100644
--- a/src/store.ts
+++ b/src/store.ts
@@ -3,6 +3,7 @@
 import { useSyncExternalStore } from 'react'
 import { api, connectEvents } from './api'
 import { applyTextDelta, applyThinkingDelta, applyToolCall, applyToolResult, applyArtifactCreated, type LiveItem } from './live'
+import { enqueueMessage, enqueueMessageFront, newQueuedMessage, promoteQueuedMessage, removeQueuedMessage, replaceQueuedText, type QueuedMessage } from './outbox'
 import type {
   Project, Conversation, Message, Run, Artifact, HITLCard, PlanSnapshot, TodoList,
   AgentProfile, StreamEvent, PluginPanel, ActivityCard,
@@ -74,6 +75,8 @@ interface AppState {
   connected: boolean
   error: string | null
   toast: string | null
+  outbox: QueuedMessage[]
+  outboxDraining: boolean
 }
 
 const DEFAULT_UI: UIState = {
@@ -112,6 +115,7 @@ let state: AppState = {
   plan: null, todos: null, artifacts: [], cards: [], projectCards: [], inboxScope: 'conv', profiles: [], pluginPanels: [],
   serverWorkspaces: [],
   ui: loadUI(), connected: false, error: null, toast: null,
+  outbox: [], outboxDraining: false,
 }
 
 const listeners = new Set<() => void>()
@@ -233,7 +237,7 @@ export const store = {
 
   async openConversation(convId: string) {
     if (sse) { sse.close(); sse = null }
-    set({ currentConvId: convId, messages: [], runs: [], activeHitl: [], lastSeq: 0, live: null, plan: null, todos: null, cards: [], inboxScope: 'conv' })
+    set({ currentConvId: convId, messages: [], runs: [], activeHitl: [], lastSeq: 0, live: null, plan: null, todos: null, cards: [], inboxScope: 'conv', outbox: [], outboxDraining: false })
     await store.reconcile()
     await store.connectLive()
   },
@@ -365,27 +369,28 @@ export const store = {
         if (p?.context && e.runId) {
           set({ contextObs: { ...state.contextObs, [e.runId]: p.context } })
         }
-        setTimeout(() => store.reconcile(), 250)
+        setTimeout(() => { void store.reconcile().then(() => store.flushOutbox()) }, 250)
         break
       }
       case 'run.failed':
       case 'error': {
-        // 终态：短暂延迟后对账（等待消息树落库），折叠过程输出。
-        setTimeout(() => store.reconcile(), 250)
+        // 终态：短暂延迟后对账（等待消息树落库），折叠过程输出，再发送排队消息。
+        setTimeout(() => { void store.reconcile().then(() => store.flushOutbox()) }, 250)
         break
       }
     }
   },
 
-  async sendMessage(text: string, attachmentIds: string[]) {
-    if (!state.currentConvId) return
+  async sendMessage(text: string, attachmentIds: string[]): Promise<'ok' | 'busy'> {
+    if (!state.currentConvId) return 'ok'
     try {
       const out = await api.sendMessage(state.currentConvId, text, attachmentIds)
       if (out.command) {
         store.toast(out.reply ?? `命令 ${out.command} 已执行`)
         if (out.conversation) await store.openConversation(out.conversation.id)
         else await store.reconcile()
-        return
+        await store.flushOutbox()
+        return 'ok'
       }
       if (out.run) {
         // 竞态保护：POST 返回前 SSE 事件可能已先行到达并累积（同 run），
@@ -396,9 +401,58 @@ export const store = {
         set({ messages: [...state.messages, out.message] })
         store.connectIfNeeded()
       }
+      return 'ok'
     } catch (e) {
+      if (isConversationBusy(e)) {
+        set({ outbox: enqueueMessageFront(state.outbox, newQueuedMessage(text, attachmentIds, [])) })
+        return 'busy'
+      }
       store.toast(`发送失败：${e}`)
       await store.reconcile()
+      return 'ok'
+    }
+  },
+
+  enqueueOutbox(text: string, attachmentIds: string[], attachmentNames: string[]) {
+    set({ outbox: enqueueMessage(state.outbox, newQueuedMessage(text, attachmentIds, attachmentNames)) })
+  },
+
+  updateOutbox(id: string, text: string) {
+    set({ outbox: replaceQueuedText(state.outbox, id, text) })
+  },
+
+  removeOutbox(id: string) {
+    set({ outbox: removeQueuedMessage(state.outbox, id) })
+  },
+
+  async sendOutboxNow(id: string) {
+    const item = state.outbox.find(q => q.id === id)
+    if (!item) return
+    const rest = removeQueuedMessage(state.outbox, id)
+    if (activeRun(state.runs) || state.live) {
+      set({ outbox: promoteQueuedMessage(state.outbox, id) })
+      store.toast('回合进行中，已放到队首，结束后自动发送')
+      return
+    }
+    set({ outbox: rest })
+    await store.sendMessage(item.text, item.attachmentIds)
+  },
+
+  async flushOutbox() {
+    if (state.outboxDraining) return
+    if (activeRun(state.runs) || state.live) return
+    const next = state.outbox[0]
+    if (!next) return
+    set({ outbox: state.outbox.slice(1), outboxDraining: true })
+    let result: 'ok' | 'busy' = 'ok'
+    try {
+      result = await store.sendMessage(next.text, next.attachmentIds)
+    } finally {
+      set({ outboxDraining: false })
+    }
+    if (result === 'busy') return
+    if (!activeRun(state.runs) && !state.live && state.outbox.length > 0) {
+      await store.flushOutbox()
     }
   },
 
@@ -623,6 +677,10 @@ export function isTerminal(status?: string): boolean {
   return status === 'completed' || status === 'failed' || status === 'cancelled' || status === 'interrupted'
 }
 
+function isConversationBusy(err: unknown): boolean {
+  return String(err).includes('409:')
+}
+
 export function activeRun(runs: Run[]): Run | undefined {
   return runs.find(r => !isTerminal(r.status))
 }
diff --git a/src/styles.css b/src/styles.css
index 3582e20..bd5adba 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -162,6 +162,11 @@ button { font-family: inherit; font-size: inherit; color: inherit; }
 
 /* 输入区：悬浮卡片式输入壳（16px 大圆角 = DESIGN.md 特批例外） */
 .input-bar { padding: 8px max(16px, 6%) 16px; background: var(--bg); border-radius: 0 0 var(--radius-lg) var(--radius-lg); }
+.outbox-trigger { width: 100%; text-align: left; background: var(--bg-inset); color: var(--text-dim); border: 1px solid var(--border-soft); border-radius: var(--radius-xs); padding: 6px 10px; font-size: var(--fs-ui-sm); cursor: pointer; }
+.outbox-list { list-style: none; margin: 6px 0 0; padding: 0; display: flex; flex-direction: column; gap: 6px; }
+.outbox-item { display: flex; gap: 6px; align-items: center; background: var(--bg-inset); border-radius: var(--radius-xs); padding: 6px 8px; }
+.outbox-text { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--text); font-size: var(--fs-ui-sm); }
+.outbox-edit { flex: 1; min-width: 0; }
 .attachments { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 8px; }
 .attach-chip { display: inline-flex; gap: 6px; align-items: center; background: var(--bg-raised); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 3px 8px; font-size: var(--fs-ui-sm); }
 .input-row { display: flex; gap: 8px; align-items: flex-end; background: var(--bg-raised); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 8px 8px 8px 14px; box-shadow: var(--shadow-md); transition: border-color .12s, box-shadow .12s; }
diff --git a/test/outbox.test.ts b/test/outbox.test.ts
new file mode 100644
index 0000000..f61fcd1
--- /dev/null
+++ b/test/outbox.test.ts
@@ -0,0 +1,28 @@
+import { describe, expect, it } from 'vitest'
+import {
+  enqueueMessage, enqueueMessageFront, newQueuedMessage, promoteQueuedMessage,
+  removeQueuedMessage, replaceQueuedText,
+} from '../src/outbox'
+
+describe('outbox', () => {
+  it('appends, edits, promotes, and removes', () => {
+    const a = newQueuedMessage('a', [], [])
+    const b = newQueuedMessage('b', ['f1'], ['note.md'])
+    let q = enqueueMessage(enqueueMessage([], a), b)
+    expect(q.map(x => x.text)).toEqual(['a', 'b'])
+    q = replaceQueuedText(q, a.id, 'a2')
+    expect(q[0].text).toBe('a2')
+    q = promoteQueuedMessage(q, b.id)
+    expect(q.map(x => x.text)).toEqual(['b', 'a2'])
+    q = removeQueuedMessage(q, b.id)
+    expect(q.map(x => x.text)).toEqual(['a2'])
+  })
+
+  it('puts a busy conflict back at the front without duplicating', () => {
+    const a = newQueuedMessage('a', [], [])
+    const b = newQueuedMessage('b', [], [])
+    const q = enqueueMessageFront(enqueueMessage([], a), b)
+    const again = enqueueMessageFront(q, b)
+    expect(again.map(x => x.id)).toEqual([b.id, a.id])
+  })
+})