feat(message-input): add search box to slash-command popups

Both the inline autocomplete (triggered by `/` in the textarea) and the
dropdown popup (triggered by the slash-command button) now show a search
field at the top. Matching uses substring on name and description, and
ranks name matches above description/id-only matches.

src/components/chat/message-input.tsx

@@ -20,6 +20,7 @@ import {
   GitFork,
   ListPlus,
   Plus,
+  Search,
   Send,
   Command,
   Sparkles,
@@ -543,19 +544,58 @@ export function MessageInput({
     () => (availableCommands ?? []).filter((cmd) => !expertIdSet.has(cmd.name)),
     [availableCommands, expertIdSet]
   )
+  const [slashDropdownOpen, setSlashDropdownOpen] = useState(false)
+  const [slashDropdownSearch, setSlashDropdownSearch] = useState("")
+  const slashDropdownInputRef = useRef<HTMLInputElement>(null)
+  const filteredSlashDropdownCommands = useMemo(() => {
+    const q = slashDropdownSearch.toLowerCase().trim()
+    if (!q) return slashCommands
+    const nameMatches: typeof slashCommands = []
+    const descOnlyMatches: typeof slashCommands = []
+    for (const cmd of slashCommands) {
+      if (cmd.name.toLowerCase().includes(q)) {
+        nameMatches.push(cmd)
+      } else if (cmd.description?.toLowerCase().includes(q)) {
+        descOnlyMatches.push(cmd)
+      }
+    }
+    return [...nameMatches, ...descOnlyMatches]
+  }, [slashCommands, slashDropdownSearch])
+  const handleSlashDropdownOpenChange = useCallback((open: boolean) => {
+    setSlashDropdownOpen(open)
+    if (!open) setSlashDropdownSearch("")
+  }, [])
+  // Radix composes this handler with its own content-focus via
+  // composeEventHandlers (default `checkForDefaultPrevented: true`), so
+  // calling preventDefault here skips radix's autofocus entirely. The prop
+  // is accepted at runtime but omitted from DropdownMenuContent's public
+  // TypeScript surface, so it has to be passed through an untyped spread.
+  const slashDropdownFocusProps = useMemo(
+    () => ({
+      onOpenAutoFocus: (event: Event) => {
+        event.preventDefault()
+        slashDropdownInputRef.current?.focus()
+      },
+    }),
+    []
+  )
+  const slashFilterText = useMemo(() => {
+    if (!slashMenuOpen || slashTriggerPos == null) return ""
+    const trigger = text[slashTriggerPos]
+    if (trigger !== "/" && trigger !== "$") return ""
+    const afterTrigger = text.slice(slashTriggerPos + 1)
+    const endIdx = afterTrigger.search(/\s/)
+    return endIdx === -1 ? afterTrigger : afterTrigger.slice(0, endIdx)
+  }, [slashMenuOpen, text, slashTriggerPos])
   const filteredSlashCommands = useMemo(() => {
     if (!slashMenuOpen || slashCommands.length === 0 || slashTriggerPos == null)
       return []
     if (text[slashTriggerPos] !== "/") return []
-    const afterTrigger = text.slice(slashTriggerPos + 1)
+    const filter = slashFilterText.toLowerCase()
-    const endIdx = afterTrigger.search(/\s/)
-    const filter = (
-      endIdx === -1 ? afterTrigger : afterTrigger.slice(0, endIdx)
-    ).toLowerCase()
     return slashCommands.filter((cmd) =>
-      cmd.name.toLowerCase().startsWith(filter)
+      cmd.name.toLowerCase().includes(filter)
     )
-  }, [slashMenuOpen, slashCommands, text, slashTriggerPos])
+  }, [slashMenuOpen, slashCommands, text, slashTriggerPos, slashFilterText])
   const filteredSlashSkills = useMemo(() => {
     // Skills autocomplete is Codex-only and triggered by `$`.
     if (agentType !== "codex") return []
@@ -566,15 +606,26 @@ export function MessageInput({
     )
       return []
     if (text[slashTriggerPos] !== "$") return []
-    const afterTrigger = text.slice(slashTriggerPos + 1)
+    const filter = slashFilterText.toLowerCase()
-    const endIdx = afterTrigger.search(/\s/)
+    if (!filter) return nonExpertSkills
-    const filter = (
+    const nameMatches: typeof nonExpertSkills = []
-      endIdx === -1 ? afterTrigger : afterTrigger.slice(0, endIdx)
+    const idOnlyMatches: typeof nonExpertSkills = []
-    ).toLowerCase()
+    for (const skill of nonExpertSkills) {
-    return nonExpertSkills.filter((skill) =>
+      if (skill.name.toLowerCase().includes(filter)) {
-      skill.id.toLowerCase().startsWith(filter)
+        nameMatches.push(skill)
-    )
+      } else if (skill.id.toLowerCase().includes(filter)) {
-  }, [slashMenuOpen, nonExpertSkills, text, agentType, slashTriggerPos])
+        idOnlyMatches.push(skill)
+      }
+    }
+    return [...nameMatches, ...idOnlyMatches]
+  }, [
+    slashMenuOpen,
+    nonExpertSkills,
+    text,
+    agentType,
+    slashTriggerPos,
+    slashFilterText,
+  ])
   const slashAutocompleteCount =
     filteredSlashCommands.length + filteredSlashSkills.length
 
@@ -950,6 +1001,25 @@ export function MessageInput({
     [onModeChange]
   )
 
+  const handleSlashSearchChange = useCallback(
+    (e: React.ChangeEvent<HTMLInputElement>) => {
+      const pos = slashTriggerPosRef.current
+      const current = textRef.current
+      if (pos == null || pos < 0 || pos >= current.length) return
+      const trigger = current[pos]
+      if (trigger !== "/" && trigger !== "$") return
+      const afterTrigger = current.slice(pos + 1)
+      const endIdx = afterTrigger.search(/\s/)
+      const tokenEnd = endIdx === -1 ? current.length : pos + 1 + endIdx
+      const before = current.slice(0, pos + 1)
+      const rest = current.slice(tokenEnd)
+      const sanitized = e.target.value.replace(/\s+/g, "")
+      setText(before + sanitized + rest)
+      setSlashSelectedIndex(0)
+    },
+    []
+  )
+
   const handleSlashSelect = useCallback((cmd: AvailableCommandInfo) => {
     const pos = slashTriggerPosRef.current
     const current = textRef.current
@@ -1046,6 +1116,49 @@ export function MessageInput({
     [expertPrefix]
   )
 
+  const handleSlashSearchKeyDown = useCallback(
+    (e: React.KeyboardEvent<HTMLInputElement>) => {
+      const total = filteredSlashCommands.length + filteredSlashSkills.length
+      if (e.key === "ArrowDown") {
+        e.preventDefault()
+        if (total === 0) return
+        setSlashSelectedIndex((i) => (i < total - 1 ? i + 1 : 0))
+        return
+      }
+      if (e.key === "ArrowUp") {
+        e.preventDefault()
+        if (total === 0) return
+        setSlashSelectedIndex((i) => (i > 0 ? i - 1 : total - 1))
+        return
+      }
+      if (e.key === "Enter" || e.key === "Tab") {
+        if (total === 0) return
+        e.preventDefault()
+        if (slashSelectedIndex < filteredSlashCommands.length) {
+          handleSlashSelect(filteredSlashCommands[slashSelectedIndex])
+        } else {
+          const skillIndex = slashSelectedIndex - filteredSlashCommands.length
+          const skill = filteredSlashSkills[skillIndex]
+          if (skill) handleSkillAutocompleteSelect(skill)
+        }
+        return
+      }
+      if (e.key === "Escape") {
+        e.preventDefault()
+        setSlashMenuOpen(false)
+        setSlashTriggerPos(null)
+        requestAnimationFrame(() => textareaRef.current?.focus())
+      }
+    },
+    [
+      filteredSlashCommands,
+      filteredSlashSkills,
+      slashSelectedIndex,
+      handleSlashSelect,
+      handleSkillAutocompleteSelect,
+    ]
+  )
+
   // Experts always inject `prefix + expert-id ` at the very front of the
   // input, never at the cursor. The expert skill is a whole-turn directive
   // that the agent inspects first, so prepending keeps semantics unambiguous
@@ -1719,10 +1832,23 @@ export function MessageInput({
       onDrop={handleContainerDrop}
     >
       {slashMenuOpen && slashAutocompleteCount > 0 && (
-        <div
+        <div className="absolute bottom-full left-0 right-0 mb-1 z-50 flex max-h-[min(16rem,40dvh)] flex-col overflow-hidden rounded-xl border border-border bg-popover shadow-lg">
-          ref={slashMenuListRef}
+          <div className="flex shrink-0 items-center gap-2 border-b border-border/60 px-3 py-2">
-          className="absolute bottom-full left-0 right-0 mb-1 z-50 max-h-[min(16rem,40dvh)] overflow-y-auto rounded-xl border border-border bg-popover p-1 shadow-lg"
+            <Search className="h-3.5 w-3.5 shrink-0 text-muted-foreground" />
-        >
+            <input
+              type="text"
+              role="searchbox"
+              aria-label={t("slashSearchPlaceholder")}
+              value={slashFilterText}
+              onChange={handleSlashSearchChange}
+              onKeyDown={handleSlashSearchKeyDown}
+              placeholder={t("slashSearchPlaceholder")}
+              className="flex-1 bg-transparent text-sm outline-none placeholder:text-muted-foreground"
+              autoComplete="off"
+              spellCheck={false}
+            />
+          </div>
+          <div ref={slashMenuListRef} className="flex-1 overflow-y-auto p-1">
             {filteredSlashCommands.map((cmd, i) => (
               <button
                 key={`cmd-${cmd.name}`}
@@ -1777,6 +1903,7 @@ export function MessageInput({
               )
             })}
           </div>
+        </div>
       )}
       {atMenuOpen && filteredAtFiles.length > 0 && (
         <FileMentionMenu
@@ -1946,7 +2073,10 @@ export function MessageInput({
                 )}
               </DropdownMenuContent>
             </DropdownMenu>
-            <DropdownMenu>
+            <DropdownMenu
+              open={slashDropdownOpen}
+              onOpenChange={handleSlashDropdownOpenChange}
+            >
               <DropdownMenuTrigger asChild>
                 <Button
                   disabled={disabled || slashCommands.length === 0}
@@ -1965,23 +2095,82 @@ export function MessageInput({
               <DropdownMenuContent
                 side="top"
                 align="start"
-                className="min-w-72 overflow-y-auto"
+                className="flex min-w-72 flex-col overflow-hidden p-0"
                 style={{
                   maxHeight:
                     "min(32rem, var(--radix-dropdown-menu-content-available-height))",
                 }}
+                {...slashDropdownFocusProps}
               >
-                {slashCommands.map((cmd) => (
+                <div className="flex shrink-0 items-center gap-2 border-b border-border/60 px-3 py-2">
+                  <Search className="h-3.5 w-3.5 shrink-0 text-muted-foreground" />
+                  <input
+                    ref={slashDropdownInputRef}
+                    type="text"
+                    role="searchbox"
+                    aria-label={t("slashSearchPlaceholder")}
+                    value={slashDropdownSearch}
+                    onChange={(e) => setSlashDropdownSearch(e.target.value)}
+                    onKeyDown={(e) => {
+                      if (e.key === "ArrowDown") {
+                        e.preventDefault()
+                        const container = e.currentTarget.closest(
+                          '[data-slot="dropdown-menu-content"]'
+                        )
+                        const firstItem =
+                          container?.querySelector<HTMLElement>(
+                            '[role="menuitem"]'
+                          )
+                        firstItem?.focus()
+                        return
+                      }
+                      if (e.key === "Enter") {
+                        e.preventDefault()
+                        const first = filteredSlashDropdownCommands[0]
+                        if (first) {
+                          handleSlashPopoverSelect(first)
+                          setSlashDropdownOpen(false)
+                        }
+                        return
+                      }
+                      if (e.key === "Escape" || e.key === "Tab") return
+                      // Prevent radix DropdownMenu's built-in typeahead from
+                      // hijacking letter keys while the user is typing.
+                      e.stopPropagation()
+                    }}
+                    placeholder={t("slashSearchPlaceholder")}
+                    className="flex-1 bg-transparent text-sm outline-none placeholder:text-muted-foreground"
+                    autoComplete="off"
+                    spellCheck={false}
+                  />
+                </div>
+                <div className="flex-1 overflow-y-auto p-1">
+                  {filteredSlashDropdownCommands.length === 0 ? (
+                    <div className="px-3 py-6 text-center text-xs text-muted-foreground">
+                      {t("slashSearchEmpty")}
+                    </div>
+                  ) : (
+                    filteredSlashDropdownCommands.map((cmd) => (
                       <DropdownMenuItem
                         key={cmd.name}
                         onClick={() => handleSlashPopoverSelect(cmd)}
+                        // Radix focuses the item on pointermove, which fires
+                        // while scrolling (items slide under the cursor) and
+                        // steals focus from the search input. Short-circuit
+                        // that default with preventDefault so the search
+                        // keeps focus until the user explicitly clicks.
+                        onPointerMove={(e) => e.preventDefault()}
+                        onPointerLeave={(e) => e.preventDefault()}
+                        className="hover:bg-accent hover:text-accent-foreground"
                       >
                         <DropdownRadioItemContent
                           label={`/${cmd.name}`}
                           description={cmd.description}
                         />
                       </DropdownMenuItem>
-                ))}
+                    ))
+                  )}
+                </div>
               </DropdownMenuContent>
             </DropdownMenu>
             {/* 宽屏内联显示，窄屏（<480px）通过"更多"气泡显示 */}

src/i18n/messages/ar.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "تفريع وإرسال",
         "slashCommands": "أوامر الشرطة المائلة",
         "expertSkills": "مهارات الخبراء",
-        "expertsEmptyForAgent": "لا يحتوي هذا العميل على خبراء مفعّلين. فعّلهم من الإعدادات > الخبراء."
+        "expertsEmptyForAgent": "لا يحتوي هذا العميل على خبراء مفعّلين. فعّلهم من الإعدادات > الخبراء.",
+        "slashSearchPlaceholder": "البحث عن الأوامر...",
+        "slashSearchEmpty": "لا توجد أوامر مطابقة"
       },
       "messageQueue": {
         "addToQueue": "إضافة للقائمة",

src/i18n/messages/de.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "Fork & Senden",
         "slashCommands": "Slash-Befehle",
         "expertSkills": "Expertenfähigkeiten",
-        "expertsEmptyForAgent": "Dieser Agent hat keine aktivierten Experten. Aktivieren Sie sie unter Einstellungen > Experten."
+        "expertsEmptyForAgent": "Dieser Agent hat keine aktivierten Experten. Aktivieren Sie sie unter Einstellungen > Experten.",
+        "slashSearchPlaceholder": "Befehle suchen...",
+        "slashSearchEmpty": "Keine passenden Befehle"
       },
       "messageQueue": {
         "addToQueue": "Zur Warteschlange",

src/i18n/messages/en.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "Fork & Send",
         "slashCommands": "Slash commands",
         "expertSkills": "Expert skills",
-        "expertsEmptyForAgent": "This agent has no enabled experts. Enable them in Settings > Experts."
+        "expertsEmptyForAgent": "This agent has no enabled experts. Enable them in Settings > Experts.",
+        "slashSearchPlaceholder": "Search commands...",
+        "slashSearchEmpty": "No matching commands"
       },
       "messageQueue": {
         "addToQueue": "Queue message",

src/i18n/messages/es.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "Fork y Enviar",
         "slashCommands": "Comandos de barra",
         "expertSkills": "Habilidades de expertos",
-        "expertsEmptyForAgent": "Este agente no tiene expertos habilitados. Actívalos en Configuración > Expertos."
+        "expertsEmptyForAgent": "Este agente no tiene expertos habilitados. Actívalos en Configuración > Expertos.",
+        "slashSearchPlaceholder": "Buscar comandos...",
+        "slashSearchEmpty": "Sin comandos coincidentes"
       },
       "messageQueue": {
         "addToQueue": "Agregar a la cola",

src/i18n/messages/fr.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "Fork & Envoyer",
         "slashCommands": "Commandes slash",
         "expertSkills": "Compétences d'expert",
-        "expertsEmptyForAgent": "Cet agent n'a aucun expert activé. Activez-les dans Paramètres > Experts."
+        "expertsEmptyForAgent": "Cet agent n'a aucun expert activé. Activez-les dans Paramètres > Experts.",
+        "slashSearchPlaceholder": "Rechercher des commandes...",
+        "slashSearchEmpty": "Aucune commande correspondante"
       },
       "messageQueue": {
         "addToQueue": "Mettre en file",

src/i18n/messages/ja.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "フォークして送信",
         "slashCommands": "スラッシュコマンド",
         "expertSkills": "エキスパートスキル",
-        "expertsEmptyForAgent": "このエージェントで有効なエキスパートはありません。「設定 > エキスパート」から有効にしてください。"
+        "expertsEmptyForAgent": "このエージェントで有効なエキスパートはありません。「設定 > エキスパート」から有効にしてください。",
+        "slashSearchPlaceholder": "コマンドを検索...",
+        "slashSearchEmpty": "一致するコマンドがありません"
       },
       "messageQueue": {
         "addToQueue": "キューに追加",

src/i18n/messages/ko.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "포크 & 전송",
         "slashCommands": "슬래시 명령",
         "expertSkills": "전문가 스킬",
-        "expertsEmptyForAgent": "이 에이전트에 활성화된 전문가가 없습니다. 설정 > 전문가에서 활성화하세요."
+        "expertsEmptyForAgent": "이 에이전트에 활성화된 전문가가 없습니다. 설정 > 전문가에서 활성화하세요.",
+        "slashSearchPlaceholder": "명령 검색...",
+        "slashSearchEmpty": "일치하는 명령이 없습니다"
       },
       "messageQueue": {
         "addToQueue": "대기열에 추가",

src/i18n/messages/pt.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "Fork & Enviar",
         "slashCommands": "Comandos de barra",
         "expertSkills": "Habilidades de especialistas",
-        "expertsEmptyForAgent": "Este agente não tem especialistas ativados. Ative-os em Configurações > Especialistas."
+        "expertsEmptyForAgent": "Este agente não tem especialistas ativados. Ative-os em Configurações > Especialistas.",
+        "slashSearchPlaceholder": "Buscar comandos...",
+        "slashSearchEmpty": "Nenhum comando correspondente"
       },
       "messageQueue": {
         "addToQueue": "Adicionar à fila",

src/i18n/messages/zh-CN.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "分叉发送",
         "slashCommands": "斜杠命令",
         "expertSkills": "专家技能",
-        "expertsEmptyForAgent": "该智能体没有启用任何专家。请在「设置 > 专家」中启用。"
+        "expertsEmptyForAgent": "该智能体没有启用任何专家。请在「设置 > 专家」中启用。",
+        "slashSearchPlaceholder": "搜索命令...",
+        "slashSearchEmpty": "没有匹配的命令"
       },
       "messageQueue": {
         "addToQueue": "加入队列",

src/i18n/messages/zh-TW.json

@@ -1573,7 +1573,9 @@
         "forkAndSend": "分叉發送",
         "slashCommands": "斜線命令",
         "expertSkills": "專家技能",
-        "expertsEmptyForAgent": "該智慧代理沒有啟用任何專家。請在「設定 > 專家」中啟用。"
+        "expertsEmptyForAgent": "該智慧代理沒有啟用任何專家。請在「設定 > 專家」中啟用。",
+        "slashSearchPlaceholder": "搜尋命令...",
+        "slashSearchEmpty": "沒有符合的指令"
       },
       "messageQueue": {
         "addToQueue": "加入佇列",