Merge pull request #578 from binaricat/fix/tool-call-duplicate-and-order

fix: resolve tool call duplication and ordering in chat UI

application/i18n/locales/en.ts

@@ -1687,6 +1687,17 @@ const en: Messages = {
   'ai.claude.customPathPlaceholder': 'e.g. /usr/local/bin/claude',
   'ai.claude.check': 'Check',
 
+  // AI GitHub Copilot CLI
+  'ai.copilot.title': 'GitHub Copilot CLI',
+  'ai.copilot.description': 'Uses GitHub Copilot CLI via ACP over stdio (`copilot --acp --stdio`). Once detected, it can be selected as an external coding agent.',
+  'ai.copilot.detecting': 'Detecting...',
+  'ai.copilot.detected': 'Detected',
+  'ai.copilot.notFound': 'Not found',
+  'ai.copilot.path': 'Path:',
+  'ai.copilot.notFoundHint': 'Could not find copilot in PATH. Install it or specify the executable path below.',
+  'ai.copilot.customPathPlaceholder': 'e.g. /usr/local/bin/copilot',
+  'ai.copilot.check': 'Check',
+
   // AI Default Agent
   'ai.defaultAgent': 'Default Agent',
   'ai.defaultAgent.description': 'Agent to use when starting a new AI session',

application/i18n/locales/zh-CN.ts

@@ -1694,6 +1694,17 @@ const zhCN: Messages = {
   'ai.claude.customPathPlaceholder': '例如 /usr/local/bin/claude',
   'ai.claude.check': '检查',
 
+  // AI GitHub Copilot CLI
+  'ai.copilot.title': 'GitHub Copilot CLI',
+  'ai.copilot.description': '通过 ACP over stdio（`copilot --acp --stdio`）接入 GitHub Copilot CLI。检测到后即可作为外部编程 Agent 使用。',
+  'ai.copilot.detecting': '检测中...',
+  'ai.copilot.detected': '已检测到',
+  'ai.copilot.notFound': '未找到',
+  'ai.copilot.path': '路径：',
+  'ai.copilot.notFoundHint': '在 PATH 中未找到 copilot。请安装或在下方指定可执行文件路径。',
+  'ai.copilot.customPathPlaceholder': '例如 /usr/local/bin/copilot',
+  'ai.copilot.check': '检查',
+
   // AI Default Agent
   'ai.defaultAgent': '默认 Agent',
   'ai.defaultAgent.description': '创建新 AI 会话时使用的 Agent',

components/AIChatSidePanel.tsx

@@ -21,6 +21,7 @@ import { useI18n } from '../application/i18n/I18nProvider';
 import { useWindowControls } from '../application/state/useWindowControls';
 import { useFileUpload } from '../application/state/useFileUpload';
 import type {
+  AgentModelPreset,
   AIPermissionMode,
   AISession,
   AISessionScope,
@@ -43,6 +44,20 @@ import { clearAllPendingApprovals } from '../infrastructure/ai/shared/approvalGa
 import { useConversationExport } from './ai/hooks/useConversationExport';
 import type { ExecutorContext } from '../infrastructure/ai/cattyAgent/executor';
 
+function isCopilotAgentConfig(agent?: ExternalAgentConfig): boolean {
+  if (!agent) return false;
+  const tokens = [
+    agent.id,
+    agent.name,
+    agent.icon,
+    agent.command,
+    agent.acpCommand,
+  ]
+    .filter((value): value is string => typeof value === 'string' && value.length > 0)
+    .map((value) => value.split('/').pop()?.toLowerCase() ?? value.toLowerCase());
+  return tokens.some((token) => token.includes('copilot'));
+}
+
 // -------------------------------------------------------------------
 // Props
 // -------------------------------------------------------------------
@@ -425,15 +440,62 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
 
   const providerDisplayName = activeProvider?.name ?? '';
   const modelDisplayName = activeModelId || activeProvider?.defaultModel || '';
+  const [runtimeAgentModelPresets, setRuntimeAgentModelPresets] = useState<Record<string, AgentModelPreset[]>>({});
 
   // Agent model presets for the current external agent
   const currentAgentConfig = useMemo(
     () => currentAgentId !== 'catty' ? externalAgents.find(a => a.id === currentAgentId) : undefined,
     [currentAgentId, externalAgents],
   );
+  const isCopilotExternalAgent = useMemo(
+    () => isCopilotAgentConfig(currentAgentConfig),
+    [currentAgentConfig],
+  );
+
+  // Ref to read agentModelMap inside the effect without re-triggering it
+  // when setAgentModel updates the map (avoids double ACP spawn).
+  const agentModelMapRef = useRef(agentModelMap);
+  agentModelMapRef.current = agentModelMap;
+
+  useEffect(() => {
+    if (!currentAgentConfig?.acpCommand) return;
+    if (!isCopilotExternalAgent) return;
+
+    const bridge = getNetcattyBridge();
+    if (!bridge?.aiAcpListModels) return;
+
+    let cancelled = false;
+    void bridge.aiAcpListModels(
+      currentAgentConfig.acpCommand,
+      currentAgentConfig.acpArgs || [],
+      undefined,
+      undefined,
+      `models_${currentAgentId}`,
+    ).then((result) => {
+      if (cancelled || !result?.ok || !Array.isArray(result.models)) return;
+      const knownModelIds = new Set(result.models.map((model) => model.id));
+      setRuntimeAgentModelPresets((prev) => ({
+        ...prev,
+        [currentAgentId]: result.models ?? [],
+      }));
+      const storedModelId = agentModelMapRef.current[currentAgentId];
+      if (result.currentModelId && (!storedModelId || !knownModelIds.has(storedModelId))) {
+        setAgentModel(currentAgentId, result.currentModelId);
+      }
+    }).catch((err) => {
+      if (!cancelled) {
+        console.warn('[AIChatSidePanel] Failed to load ACP agent models:', err);
+      }
+    });
+
+    return () => {
+      cancelled = true;
+    };
+  }, [currentAgentConfig, currentAgentId, isCopilotExternalAgent, setAgentModel]);
+
   const agentModelPresets = useMemo(
-    () => getAgentModelPresets(currentAgentConfig?.command),
-    [currentAgentConfig?.command],
+    () => runtimeAgentModelPresets[currentAgentId] ?? getAgentModelPresets(currentAgentConfig?.command),
+    [currentAgentId, currentAgentConfig?.command, runtimeAgentModelPresets],
   );
 
   // Per-agent model: recall last selection or use first preset as default
@@ -593,7 +655,9 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
     const assistantMsgId = generateId();
     addMessageToSession(sessionId, {
       id: assistantMsgId, role: 'assistant', content: '', timestamp: Date.now(),
-      model: isExternalAgent ? (agentConfig?.name || 'external') : (activeModelId || activeProvider?.defaultModel || ''),
+      model: isExternalAgent
+        ? (selectedAgentModel || agentConfig?.name || 'external')
+        : (activeModelId || activeProvider?.defaultModel || ''),
       providerId: isExternalAgent ? undefined : activeProvider?.providerId,
     });
 

components/Terminal.tsx

@@ -1963,6 +1963,7 @@ const TerminalComponent: React.FC<TerminalProps> = ({
                 containerRef={containerRef}
                 onRequestReposition={autocomplete.repositionPopup}
                 searchBarOffset={isSearchOpen ? 64 : 30}
+                onDismiss={autocompleteClosePopup}
               />,
               document.body,
             )

components/ai/AgentIconBadge.tsx

@@ -11,6 +11,7 @@ type AgentLike = {
 
 type AgentIconKey =
   | 'catty'
+  | 'copilot'
   | 'openai'
   | 'claude'
   | 'anthropic'
@@ -20,7 +21,7 @@ type AgentIconKey =
   | 'openrouter'
   | 'zed'
   | 'atom'
-| 'terminal'
+  | 'terminal'
   | 'plus';
 
 type AgentIconVisual = {
@@ -35,6 +36,11 @@ const AGENT_ICON_VISUALS: Record<AgentIconKey, AgentIconVisual> = {
     badgeClassName: 'border-violet-500/20 bg-violet-500/10',
     imageClassName: 'object-contain dark:brightness-0 dark:invert opacity-90',
   },
+  copilot: {
+    src: '/ai/agents/copilot.svg',
+    badgeClassName: 'border-zinc-300 bg-white',
+    imageClassName: 'object-contain brightness-0',
+  },
   openai: {
     src: '/ai/providers/openai.svg',
     badgeClassName: 'border-emerald-500/22 bg-emerald-500/12',
@@ -115,6 +121,9 @@ function getAgentIconKey(agent: AgentLike | 'add-more'): AgentIconKey {
   if (tokens.some((token) => token.includes('claude'))) {
     return 'claude';
   }
+  if (tokens.some((token) => token.includes('copilot'))) {
+    return 'copilot';
+  }
   if (tokens.some((token) => token.includes('anthropic'))) {
     return 'anthropic';
   }
@@ -160,7 +169,8 @@ export const AgentIconBadge: React.FC<{
   variant?: 'plain' | 'badge';
   className?: string;
 }> = ({ agent, size = 'md', variant = 'badge', className }) => {
-  const visual = AGENT_ICON_VISUALS[getAgentIconKey(agent)];
+  const iconKey = getAgentIconKey(agent);
+  const visual = AGENT_ICON_VISUALS[iconKey];
   const badgeSize =
     size === 'xs'
       ? 'h-4 w-4 rounded-sm'

components/ai/AgentSelector.tsx

@@ -9,6 +9,10 @@ import { ChevronDown, RefreshCw, Plus, Settings } from 'lucide-react';
 import React, { useCallback, useMemo, useState } from 'react';
 import { cn } from '../../lib/utils';
 import { useI18n } from '../../application/i18n/I18nProvider';
+import {
+  isSettingsManagedDiscoveredAgent,
+  matchesManagedAgentConfig,
+} from '../../infrastructure/ai/managedAgents';
 import type { AgentInfo, ExternalAgentConfig, DiscoveredAgent } from '../../infrastructure/ai/types';
 import AgentIconBadge from './AgentIconBadge';
 import {
@@ -140,7 +144,12 @@ const AgentSelector: React.FC<AgentSelectorProps> = ({
   const unconfiguredDiscovered = useMemo(
     () =>
       discoveredAgents.filter(
-        (da) => !externalAgents.some((ea) => ea.command === da.command || ea.command === da.path),
+        (da) => {
+          if (isSettingsManagedDiscoveredAgent(da)) {
+            return !externalAgents.some((ea) => matchesManagedAgentConfig(ea, da.command));
+          }
+          return !externalAgents.some((ea) => ea.command === da.command || ea.command === da.path);
+        },
       ),
     [discoveredAgents, externalAgents],
   );

components/ai/ChatMessageList.tsx

@@ -238,8 +238,13 @@ const ChatMessageList: React.FC<ChatMessageListProps> = ({ messages, isStreaming
                       </MessageResponse>
                 )}
 
-                {/* Tool calls */}
-                {message.toolCalls?.map((tc) => {
+                {/* Pending tool calls from the *last* assistant message are rendered
+                    after all tool-result messages (see below) for chronological order.
+                    Unresolved tool calls from earlier or cancelled messages are shown
+                    inline — as interrupted, or with approval controls if still pending. */}
+                {(message !== lastAssistantMessage || message.executionStatus === 'cancelled') && message.toolCalls?.filter((tc) =>
+                  !resolvedToolCallIds.has(tc.id),
+                ).map((tc) => {
                   const isPending = pendingApprovals.has(tc.id);
                   const resolved = resolvedApprovals.get(tc.id);
                   const approvalStatus = isPending
@@ -249,14 +254,12 @@ const ChatMessageList: React.FC<ChatMessageListProps> = ({ messages, isStreaming
                       : resolved === false
                         ? 'denied' as const
                         : undefined;
-
                   return (
                     <ToolCall
                       key={tc.id}
                       name={tc.name}
                       args={tc.arguments}
-                      isLoading={isThisStreaming && message.executionStatus === 'running' && !isPending}
-                      isInterrupted={message.executionStatus === 'cancelled' && !resolvedToolCallIds.has(tc.id)}
+                      isInterrupted={!isPending}
                       approvalStatus={approvalStatus}
                       onApprove={() => handleApprove(tc.id)}
                       onReject={() => handleReject(tc.id)}
@@ -290,6 +293,33 @@ const ChatMessageList: React.FC<ChatMessageListProps> = ({ messages, isStreaming
           );
         })}
 
+        {/* Pending tool calls from the last assistant message — rendered here
+            (after all tool-result messages) so they appear at the bottom. */}
+        {lastAssistantMessage?.toolCalls?.filter((tc) =>
+          !resolvedToolCallIds.has(tc.id) && lastAssistantMessage.executionStatus !== 'cancelled',
+        ).map((tc) => {
+          const isPending = pendingApprovals.has(tc.id);
+          const resolved = resolvedApprovals.get(tc.id);
+          const approvalStatus = isPending
+            ? 'pending' as const
+            : resolved === true
+              ? 'approved' as const
+              : resolved === false
+                ? 'denied' as const
+                : undefined;
+          return (
+            <ToolCall
+              key={tc.id}
+              name={tc.name}
+              args={tc.arguments}
+              isLoading={isStreaming && lastAssistantMessage.executionStatus === 'running' && !isPending}
+              approvalStatus={approvalStatus}
+              onApprove={() => handleApprove(tc.id)}
+              onReject={() => handleReject(tc.id)}
+            />
+          );
+        })}
+
         {/* Standalone MCP/ACP approval requests (not tied to SDK tool calls) */}
         {Array.from(pendingApprovals.entries())
           .filter((entry) => entry[0].startsWith('mcp_approval_') && (!activeSessionId || entry[1].chatSessionId === activeSessionId))

components/ai/hooks/useAIChatStreaming.ts

@@ -112,6 +112,13 @@ export interface PanelBridge extends NetcattyBridge {
   aiSyncProviders?: (providers: Array<{ id: string; providerId: string; apiKey?: string; baseURL?: string; enabled: boolean }>) => Promise<{ ok: boolean }>;
   aiSyncWebSearch?: (apiHost: string | null, apiKey: string | null) => Promise<{ ok: boolean }>;
   aiMcpUpdateSessions?: (sessions: TerminalSessionInfo[], chatSessionId?: string) => Promise<unknown>;
+  aiAcpListModels?: (
+    acpCommand: string,
+    acpArgs?: string[],
+    cwd?: string,
+    providerId?: string,
+    chatSessionId?: string,
+  ) => Promise<{ ok: boolean; models?: Array<{ id: string; name: string; description?: string }>; currentModelId?: string | null; error?: string }>;
   aiAcpCleanup?: (chatSessionId: string) => Promise<{ ok: boolean }>;
   [key: string]: ((...args: unknown[]) => unknown) | undefined;
 }

components/settings/tabs/SettingsAITab.tsx

@@ -8,7 +8,7 @@
  *   - SafetySettings
  */
 import { Bot, Globe } from "lucide-react";
-import React, { useCallback, useEffect, useMemo, useState } from "react";
+import React, { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import type {
   AIPermissionMode,
   AIProviderId,
@@ -16,8 +16,12 @@ import type {
   ProviderConfig,
   WebSearchConfig,
 } from "../../../infrastructure/ai/types";
+import {
+  getManagedAgentStoredPath,
+  matchesManagedAgentConfig,
+  type ManagedAgentKey,
+} from "../../../infrastructure/ai/managedAgents";
 import { PROVIDER_PRESETS } from "../../../infrastructure/ai/types";
-import { useAgentDiscovery } from "../../../application/state/useAgentDiscovery";
 import { useI18n } from "../../../application/i18n/I18nProvider";
 import { TabsContent } from "../../ui/tabs";
 import { Select, SettingRow } from "../settings-ui";
@@ -38,6 +42,7 @@ import { ProviderCard } from "./ai/ProviderCard";
 import { AddProviderDropdown } from "./ai/AddProviderDropdown";
 import { CodexConnectionCard } from "./ai/CodexConnectionCard";
 import { ClaudeCodeCard } from "./ai/ClaudeCodeCard";
+import { CopilotCliCard } from "./ai/CopilotCliCard";
 import { SafetySettings } from "./ai/SafetySettings";
 import { WebSearchSettings } from "./ai/WebSearchSettings";
 
@@ -70,6 +75,54 @@ interface SettingsAITabProps {
   setWebSearchConfig: (config: WebSearchConfig | null) => void;
 }
 
+function areExternalAgentListsEqual(
+  left: ExternalAgentConfig[],
+  right: ExternalAgentConfig[],
+): boolean {
+  if (left.length !== right.length) return false;
+  return left.every((agent, index) => JSON.stringify(agent) === JSON.stringify(right[index]));
+}
+
+function buildManagedAgentState(
+  prevAgents: ExternalAgentConfig[],
+  defaultAgentId: string,
+  agentKey: ManagedAgentKey,
+  pathInfo: AgentPathInfo | null,
+): { agents: ExternalAgentConfig[]; defaultAgentId: string } {
+  const managedId = `discovered_${agentKey}`;
+  const managedAgents = prevAgents.filter((agent) => matchesManagedAgentConfig(agent, agentKey));
+  const otherAgents = prevAgents.filter((agent) => !matchesManagedAgentConfig(agent, agentKey));
+  const storedPath = getManagedAgentStoredPath(prevAgents, agentKey);
+
+  if (!pathInfo?.available || !pathInfo.path) {
+    return {
+      agents: storedPath ? prevAgents : otherAgents,
+      defaultAgentId: storedPath
+        ? defaultAgentId
+        : managedAgents.some((agent) => agent.id === defaultAgentId)
+          ? "catty"
+          : defaultAgentId,
+    };
+  }
+
+  const existingManaged = managedAgents.find((agent) => agent.id === managedId);
+  const defaults = AGENT_DEFAULTS[agentKey];
+  const nextManagedAgent: ExternalAgentConfig = {
+    ...existingManaged,
+    ...defaults,
+    id: managedId,
+    command: pathInfo.path,
+    enabled: managedAgents.length === 0 ? true : managedAgents.some((agent) => agent.enabled),
+  };
+
+  return {
+    agents: [...otherAgents, nextManagedAgent],
+    defaultAgentId: managedAgents.some((agent) => agent.id === defaultAgentId)
+      ? managedId
+      : defaultAgentId,
+  };
+}
+
 // ---------------------------------------------------------------------------
 // Main Tab Component
 // ---------------------------------------------------------------------------
@@ -113,58 +166,44 @@ const SettingsAITab: React.FC<SettingsAITabProps> = ({
   const [claudePathInfo, setClaudePathInfo] = useState<AgentPathInfo | null>(null);
   const [claudeCustomPath, setClaudeCustomPath] = useState("");
   const [isResolvingClaude, setIsResolvingClaude] = useState(false);
+  const initialManagedPathsRef = useRef<{
+    codex: string;
+    claude: string;
+    copilot: string;
+  } | null>(null);
+  if (!initialManagedPathsRef.current) {
+    initialManagedPathsRef.current = {
+      codex: getManagedAgentStoredPath(externalAgents, "codex") ?? "",
+      claude: getManagedAgentStoredPath(externalAgents, "claude") ?? "",
+      copilot: getManagedAgentStoredPath(externalAgents, "copilot") ?? "",
+    };
+  }
 
-  const {
-    discoveredAgents,
-    isDiscovering,
-    enableAgent,
-  } = useAgentDiscovery(externalAgents, setExternalAgents);
+  const [copilotPathInfo, setCopilotPathInfo] = useState<AgentPathInfo | null>(null);
+  const [copilotCustomPath, setCopilotCustomPath] = useState("");
+  const [isResolvingCopilot, setIsResolvingCopilot] = useState(false);
 
-  // Derive path info from discovery results
-  useEffect(() => {
-    if (isDiscovering) return;
+  // Ref to read current defaultAgentId without adding it as a dependency.
+  const defaultAgentIdRef = useRef(defaultAgentId);
+  defaultAgentIdRef.current = defaultAgentId;
 
-    const codex = discoveredAgents.find((a) => a.command === "codex");
-    setCodexPathInfo(
-      codex
-        ? { path: codex.path, version: codex.version, available: true }
-        : { path: null, version: null, available: false },
-    );
-
-    const claude = discoveredAgents.find((a) => a.command === "claude");
-    setClaudePathInfo(
-      claude
-        ? { path: claude.path, version: claude.version, available: true }
-        : { path: null, version: null, available: false },
-    );
-  }, [isDiscovering, discoveredAgents]);
-
-  // Auto-register discovered agents in externalAgents
-  useEffect(() => {
-    if (isDiscovering || discoveredAgents.length === 0) return;
-
-    setExternalAgents((prev) => {
-      const agentsToRegister: ExternalAgentConfig[] = [];
-
-      for (const da of discoveredAgents) {
-        if (da.command !== "codex" && da.command !== "claude") continue;
-        const agentId = `discovered_${da.command}`;
-        if (prev.some((ea) => ea.id === agentId)) continue;
-        agentsToRegister.push(enableAgent(da));
-      }
-
-      return agentsToRegister.length > 0 ? [...prev, ...agentsToRegister] : prev;
-    });
-  }, [isDiscovering, discoveredAgents, enableAgent, setExternalAgents]);
-
-  // Validate a custom path for an agent
-  const handleCheckCustomPath = useCallback(async (agentKey: "codex" | "claude") => {
+  const resolveAgentPath = useCallback(async (
+    agentKey: ManagedAgentKey,
+    customPath = "",
+  ) => {
     const bridge = getBridge();
-    if (!bridge?.aiResolveCli) return;
+    if (!bridge?.aiResolveCli) return null;
 
-    const customPath = agentKey === "codex" ? codexCustomPath : claudeCustomPath;
-    const setInfo = agentKey === "codex" ? setCodexPathInfo : setClaudePathInfo;
-    const setResolving = agentKey === "codex" ? setIsResolvingCodex : setIsResolvingClaude;
+    const setInfo = agentKey === "codex"
+      ? setCodexPathInfo
+      : agentKey === "claude"
+        ? setClaudePathInfo
+        : setCopilotPathInfo;
+    const setResolving = agentKey === "codex"
+      ? setIsResolvingCodex
+      : agentKey === "claude"
+        ? setIsResolvingClaude
+        : setIsResolvingCopilot;
 
     setResolving(true);
     try {
@@ -174,32 +213,48 @@ const SettingsAITab: React.FC<SettingsAITabProps> = ({
       });
       setInfo(result);
 
-      // Register/update in externalAgents if valid
-      if (result.available && result.path) {
-        const agentId = `discovered_${agentKey}`;
-        const defaults = AGENT_DEFAULTS[agentKey];
-        setExternalAgents((prev) => {
-          const idx = prev.findIndex((a) => a.id === agentId);
-          const config: ExternalAgentConfig = {
-            id: agentId,
-            command: result.path!,
-            enabled: true,
-            ...defaults,
-          };
-          if (idx >= 0) {
-            const updated = [...prev];
-            updated[idx] = { ...updated[idx], command: result.path! };
-            return updated;
-          }
-          return [...prev, config];
-        });
+      // Consolidate managed agent entries using the callback form of
+      // setExternalAgents so we never depend on externalAgents directly.
+      // All three agents resolve concurrently on mount — React runs
+      // state updater callbacks sequentially, so updating the ref inside
+      // ensures later calls see earlier defaultAgentId changes.
+      let nextDefaultId: string | null = null;
+      setExternalAgents((prev) => {
+        const state = buildManagedAgentState(prev, defaultAgentIdRef.current, agentKey, result);
+        if (state.defaultAgentId !== defaultAgentIdRef.current) {
+          nextDefaultId = state.defaultAgentId;
+          defaultAgentIdRef.current = state.defaultAgentId;
+        }
+        return areExternalAgentListsEqual(prev, state.agents) ? prev : state.agents;
+      });
+      if (nextDefaultId !== null) {
+        setDefaultAgentId(nextDefaultId);
       }
+
+      return result;
     } catch (err) {
       console.error("Path resolution failed:", err);
+      return null;
     } finally {
       setResolving(false);
     }
-  }, [codexCustomPath, claudeCustomPath, setExternalAgents]);
+  }, [setExternalAgents, setDefaultAgentId]);
+
+  useEffect(() => {
+    void resolveAgentPath("codex", initialManagedPathsRef.current?.codex ?? "");
+    void resolveAgentPath("claude", initialManagedPathsRef.current?.claude ?? "");
+    void resolveAgentPath("copilot", initialManagedPathsRef.current?.copilot ?? "");
+  }, [resolveAgentPath]);
+
+  // Validate a custom path for an agent
+  const handleCheckCustomPath = useCallback(async (agentKey: ManagedAgentKey) => {
+    const customPath = agentKey === "codex"
+      ? codexCustomPath
+      : agentKey === "claude"
+        ? claudeCustomPath
+        : copilotCustomPath;
+    await resolveAgentPath(agentKey, customPath);
+  }, [claudeCustomPath, codexCustomPath, copilotCustomPath, resolveAgentPath]);
 
   // Add a new provider from preset
   const handleAddProvider = useCallback(
@@ -457,7 +512,7 @@ const SettingsAITab: React.FC<SettingsAITabProps> = ({
 
             <CodexConnectionCard
               pathInfo={codexPathInfo}
-              isResolvingPath={isDiscovering || isResolvingCodex}
+              isResolvingPath={isResolvingCodex}
               customPath={codexCustomPath}
               onCustomPathChange={setCodexCustomPath}
               onRecheckPath={() => void handleCheckCustomPath("codex")}
@@ -483,13 +538,29 @@ const SettingsAITab: React.FC<SettingsAITabProps> = ({
 
             <ClaudeCodeCard
               pathInfo={claudePathInfo}
-              isResolvingPath={isDiscovering || isResolvingClaude}
+              isResolvingPath={isResolvingClaude}
               customPath={claudeCustomPath}
               onCustomPathChange={setClaudeCustomPath}
               onRecheckPath={() => void handleCheckCustomPath("claude")}
             />
           </div>
 
+          {/* -- GitHub Copilot CLI Section -- */}
+          <div className="space-y-4">
+            <div className="flex items-center gap-2">
+              <ProviderIconBadge providerId="copilot" size="sm" />
+              <h3 className="text-base font-medium">{t('ai.copilot.title')}</h3>
+            </div>
+
+            <CopilotCliCard
+              pathInfo={copilotPathInfo}
+              isResolvingPath={isResolvingCopilot}
+              customPath={copilotCustomPath}
+              onCustomPathChange={setCopilotCustomPath}
+              onRecheckPath={() => void handleCheckCustomPath("copilot")}
+            />
+          </div>
+
           {/* -- Default Agent Section -- */}
           {agentOptions.length > 1 && (
             <div className="space-y-4">
@@ -507,7 +578,7 @@ const SettingsAITab: React.FC<SettingsAITabProps> = ({
                     value={defaultAgentId}
                     options={agentOptions}
                     onChange={setDefaultAgentId}
-                    className="w-48"
+                    className="w-64"
                   />
                 </SettingRow>
               </div>

components/settings/tabs/ai/CopilotCliCard.tsx

@@ -0,0 +1,87 @@
+import React from "react";
+import { RefreshCw } from "lucide-react";
+import { useI18n } from "../../../../application/i18n/I18nProvider";
+import { Button } from "../../../ui/button";
+import { cn } from "../../../../lib/utils";
+import type { AgentPathInfo } from "./types";
+import { ProviderIconBadge } from "./ProviderIconBadge";
+
+export const CopilotCliCard: React.FC<{
+  pathInfo: AgentPathInfo | null;
+  isResolvingPath: boolean;
+  customPath: string;
+  onCustomPathChange: (path: string) => void;
+  onRecheckPath: () => void;
+}> = ({
+  pathInfo,
+  isResolvingPath,
+  customPath,
+  onCustomPathChange,
+  onRecheckPath,
+}) => {
+  const { t } = useI18n();
+  const found = pathInfo?.available;
+
+  const statusText = isResolvingPath
+    ? t('ai.copilot.detecting')
+    : found
+      ? t('ai.copilot.detected')
+      : t('ai.copilot.notFound');
+
+  const statusClassName = isResolvingPath
+    ? "text-muted-foreground"
+    : found
+      ? "text-emerald-500"
+      : "text-amber-500";
+
+  return (
+    <div className="rounded-lg border border-border/60 bg-muted/20 p-4 space-y-3">
+      <div className="flex items-start justify-between gap-4">
+        <div className="min-w-0">
+          <div className="flex items-center gap-2">
+            <ProviderIconBadge providerId="copilot" size="sm" />
+            <span className="text-sm font-medium">{t('ai.copilot.title')}</span>
+          </div>
+          <p className="text-xs text-muted-foreground mt-2 leading-5">
+            {t('ai.copilot.description')}
+          </p>
+        </div>
+        <div className={cn("text-xs font-medium shrink-0", statusClassName)}>
+          {statusText}
+        </div>
+      </div>
+
+      {found ? (
+        <div className="flex items-center gap-2 text-xs">
+          <span className="text-muted-foreground">{t('ai.copilot.path')}</span>
+          <span className="font-mono text-foreground truncate">{pathInfo.path}</span>
+          {pathInfo.version && (
+            <>
+              <span className="text-muted-foreground">|</span>
+              <span className="text-muted-foreground">{pathInfo.version}</span>
+            </>
+          )}
+        </div>
+      ) : !isResolvingPath ? (
+        <div className="space-y-2">
+          <p className="text-xs text-amber-500">
+            {t('ai.copilot.notFoundHint')}
+          </p>
+          <div className="flex items-center gap-2">
+            <input
+              type="text"
+              value={customPath}
+              onChange={(e) => onCustomPathChange(e.target.value)}
+              placeholder={t('ai.copilot.customPathPlaceholder')}
+              className="flex-1 h-8 rounded-md border border-input bg-background px-3 text-sm font-mono placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring"
+            />
+            <Button variant="outline" size="sm" onClick={onRecheckPath} disabled={!customPath.trim()}>
+              <RefreshCw size={14} className="mr-1.5" />
+              {t('ai.copilot.check')}
+            </Button>
+          </div>
+        </div>
+      ) : null}
+    </div>
+  );
+};

components/settings/tabs/ai/ProviderIconBadge.tsx

@@ -20,7 +20,8 @@ export const ProviderIconBadge: React.FC<{
       aria-hidden="true"
       draggable={false}
       className={cn(
-        "object-contain brightness-0 invert",
+        "object-contain",
+        providerId === "copilot" ? "brightness-0" : "brightness-0 invert",
         size === "sm" ? "w-3 h-3" : "w-4 h-4",
       )}
     />

components/settings/tabs/ai/index.ts

@@ -5,4 +5,5 @@ export { ProviderCard } from "./ProviderCard";
 export { AddProviderDropdown } from "./AddProviderDropdown";
 export { CodexConnectionCard } from "./CodexConnectionCard";
 export { ClaudeCodeCard } from "./ClaudeCodeCard";
+export { CopilotCliCard } from "./CopilotCliCard";
 export { SafetySettings } from "./SafetySettings";

components/settings/tabs/ai/types.ts

@@ -82,6 +82,13 @@ export const AGENT_DEFAULTS: Record<string, Omit<ExternalAgentConfig, "id" | "co
     acpCommand: "claude-agent-acp",
     acpArgs: [],
   },
+  copilot: {
+    name: "GitHub Copilot CLI",
+    args: ["-p", "{prompt}"],
+    icon: "copilot",
+    acpCommand: "copilot",
+    acpArgs: ["--acp", "--stdio"],
+  },
 };
 
 // ---------------------------------------------------------------------------
@@ -108,12 +115,13 @@ export function normalizeCodexBridgeError(error: unknown): string {
 // Provider icon helper
 // ---------------------------------------------------------------------------
 
-export type SettingsIconId = AIProviderId | "claude";
+export type SettingsIconId = AIProviderId | "claude" | "copilot";
 
 export const SETTINGS_ICON_PATHS: Record<SettingsIconId, string> = {
   openai: "/ai/providers/openai.svg",
   anthropic: "/ai/providers/anthropic.svg",
   claude: "/ai/agents/claude.svg",
+  copilot: "/ai/agents/copilot.svg",
   google: "/ai/providers/google.svg",
   ollama: "/ai/providers/ollama.svg",
   openrouter: "/ai/providers/openrouter.svg",
@@ -124,6 +132,7 @@ export const SETTINGS_ICON_COLORS: Record<SettingsIconId, string> = {
   openai: "bg-emerald-600",
   anthropic: "bg-orange-600",
   claude: "bg-orange-600",
+  copilot: "border border-zinc-300 bg-white",
   google: "bg-blue-600",
   ollama: "bg-purple-600",
   openrouter: "bg-pink-600",

components/terminal/autocomplete/AutocompletePopup.tsx

@@ -48,6 +48,8 @@ interface AutocompletePopupProps {
   onRequestReposition?: () => void;
   /** Offset from top of container to terminal content area (toolbar + search bar) */
   searchBarOffset?: number;
+  /** Called when user clicks outside the popup to dismiss it */
+  onDismiss?: () => void;
 }
 
 const SOURCE_LABELS: Record<SuggestionSource, { label: string; fullLabel: string; fallbackColor: string }> = {
@@ -105,7 +107,9 @@ const AutocompletePopup: React.FC<AutocompletePopupProps> = ({
   containerRef,
   onRequestReposition,
   searchBarOffset: _searchBarOffset = 30,
+  onDismiss,
 }) => {
+  const wrapperRef = useRef<HTMLDivElement>(null);
   const listRef = useRef<HTMLDivElement>(null);
   const selectedRef = useRef<HTMLDivElement>(null);
   const [hoveredIndex, setHoveredIndex] = useState(-1);
@@ -148,6 +152,18 @@ const AutocompletePopup: React.FC<AutocompletePopupProps> = ({
     };
   }, [containerRef, onRequestReposition, visible]);
 
+  // Dismiss popup when clicking outside
+  useEffect(() => {
+    if (!visible || !onDismiss) return;
+    const handlePointerDown = (e: PointerEvent) => {
+      if (wrapperRef.current && !wrapperRef.current.contains(e.target as Node)) {
+        onDismiss();
+      }
+    };
+    document.addEventListener("pointerdown", handlePointerDown);
+    return () => document.removeEventListener("pointerdown", handlePointerDown);
+  }, [visible, onDismiss]);
+
   if (!visible || suggestions.length === 0) return null;
 
   const bg = themeColors?.background ?? "#1e1e2e";
@@ -217,6 +233,7 @@ const AutocompletePopup: React.FC<AutocompletePopupProps> = ({
 
   return (
     <div
+      ref={wrapperRef}
       style={{
         position: "fixed",
         left: `${clampedLeft}px`,

electron/bridges/aiBridge.cjs

@@ -7,9 +7,11 @@
 
 const https = require("node:https");
 const http = require("node:http");
+const path = require("node:path");
 const { URL } = require("node:url");
 const { spawn, execFileSync } = require("node:child_process");
-const { existsSync } = require("node:fs");
+const fs = require("node:fs");
+const { existsSync } = fs;
 
 const mcpServerBridge = require("./mcpServerBridge.cjs");
 
@@ -60,7 +62,6 @@ const acpProviders = new Map();
 const acpActiveStreams = new Map();
 const acpRequestSessions = new Map();
 const acpPendingCancelRequests = new Set();
-const acpForceProviderReset = new Set();
 const acpChatRuns = new Map();
 
 // ── Provider registry (synced from renderer, keys stay encrypted) ──
@@ -141,21 +142,39 @@ function injectApiKeyIntoRequest(url, headers, providerId) {
 }
 
 function cleanupAcpProvider(chatSessionId) {
+  // Clean up temporary COPILOT_HOME directory regardless of whether a
+  // provider entry exists — prepareCopilotHome may have succeeded before
+  // provider creation failed.
+  try {
+    const tempDirBridge = require("./tempDirBridge.cjs");
+    const tempCopilotHome = path.join(tempDirBridge.getTempDir(), `copilot-home-${chatSessionId}`);
+    if (existsSync(tempCopilotHome)) {
+      fs.rmSync(tempCopilotHome, { recursive: true, force: true });
+    }
+  } catch {
+    // Best-effort cleanup
+  }
+
   const entry = acpProviders.get(chatSessionId);
   if (!entry) return;
-  const rootPid = entry.provider?.model?.agentProcess?.pid;
+  cleanupAcpProviderInstance(entry.provider, chatSessionId);
+  acpProviders.delete(chatSessionId);
+}
+
+function cleanupAcpProviderInstance(provider, chatSessionId = "transient") {
+  if (!provider) return;
+  const rootPid = provider?.model?.agentProcess?.pid;
   const childPids = getChildProcessTreePids(rootPid);
   try {
-    if (typeof entry.provider.forceCleanup === "function") {
-      entry.provider.forceCleanup();
-    } else if (typeof entry.provider.cleanup === "function") {
-      entry.provider.cleanup();
+    if (typeof provider.forceCleanup === "function") {
+      provider.forceCleanup();
+    } else if (typeof provider.cleanup === "function") {
+      provider.cleanup();
     }
   } catch (err) {
     console.warn("[ACP] Provider cleanup failed for session", chatSessionId, err?.message || err);
   }
   killTrackedProcessTree(rootPid, childPids);
-  acpProviders.delete(chatSessionId);
 }
 
 function isActiveAcpRun(chatSessionId, requestId) {
@@ -163,9 +182,10 @@ function isActiveAcpRun(chatSessionId, requestId) {
   return Boolean(activeRun && activeRun.requestId === requestId);
 }
 
-function isUnsupportedLoadSessionError(err) {
+function shouldRetryFreshSession(err) {
   const message = String(err?.message || err || "").toLowerCase();
-  return message.includes("method not found") && message.includes("session/load");
+  return (message.includes("method not found") && message.includes("session/load"))
+    || (message.includes("resource not found") && message.includes("session") && message.includes("not found"));
 }
 
 function getChildProcessTreePids(rootPid) {
@@ -302,6 +322,127 @@ function _validateSenderImpl(event, allowSettings) {
   }
 }
 
+function summarizeMcpServersForDebug(mcpServers) {
+  if (!Array.isArray(mcpServers)) return [];
+  return mcpServers.map((server) => ({
+    name: server?.name || "",
+    type: server?.type || "",
+    command: server?.command || "",
+    args: Array.isArray(server?.args) ? server.args : [],
+    hasEnv: Array.isArray(server?.env) ? server.env.length > 0 : false,
+    url: server?.url || "",
+  }));
+}
+
+function logAcpDebug(agentLabel, message, details) {
+  const prefix = `[ACP DEBUG][${agentLabel}]`;
+  if (details === undefined) {
+    console.log(prefix, message);
+    return;
+  }
+  try {
+    console.log(prefix, message, JSON.stringify(details));
+  } catch {
+    console.log(prefix, message, details);
+  }
+}
+
+function normalizeAgentCommandName(command) {
+  if (typeof command !== "string" || !command) return "";
+  return path.basename(command).toLowerCase().replace(/\.(exe|cmd|bat|ps1)$/i, "");
+}
+
+function matchesAgentCommand(command, expectedName) {
+  if (typeof command !== "string" || typeof expectedName !== "string") return false;
+  if (command.toLowerCase() === expectedName.toLowerCase()) return true;
+  return normalizeAgentCommandName(command) === normalizeAgentCommandName(expectedName);
+}
+
+function envPairsToObject(entries) {
+  if (!Array.isArray(entries)) return {};
+  const result = {};
+  for (const entry of entries) {
+    if (!entry || typeof entry.name !== "string") continue;
+    result[entry.name] = entry.value == null ? "" : String(entry.value);
+  }
+  return result;
+}
+
+function mapMcpServerToCopilotConfig(server) {
+  if (!server || typeof server !== "object" || !server.name) return null;
+
+  if (server.type === "stdio" || server.type === "local") {
+    return {
+      type: "local",
+      command: server.command || "",
+      args: Array.isArray(server.args) ? server.args : [],
+      env: envPairsToObject(server.env),
+      tools: ["*"],
+    };
+  }
+
+  if (server.type === "http" || server.type === "sse") {
+    return {
+      type: server.type,
+      url: server.url || "",
+      headers: envPairsToObject(server.headers),
+      tools: ["*"],
+    };
+  }
+
+  return null;
+}
+
+function safeReadJson(filePath) {
+  try {
+    if (!existsSync(filePath)) return null;
+    return JSON.parse(fs.readFileSync(filePath, "utf8"));
+  } catch {
+    return null;
+  }
+}
+
+function prepareCopilotHome(shellEnv, mcpServers, chatSessionId) {
+  const tempDirBridge = require("./tempDirBridge.cjs");
+  const homeDir = shellEnv.HOME || process.env.HOME || process.env.USERPROFILE || "";
+  const realCopilotHome = shellEnv.COPILOT_HOME || path.join(homeDir, ".copilot");
+  const tempCopilotHome = path.join(tempDirBridge.getTempDir(), `copilot-home-${chatSessionId}`);
+
+  try {
+    fs.rmSync(tempCopilotHome, { recursive: true, force: true });
+  } catch {
+    // Ignore cleanup failures; mkdir/copy below will surface real issues if any.
+  }
+
+  fs.mkdirSync(tempCopilotHome, { recursive: true });
+
+  if (realCopilotHome && existsSync(realCopilotHome)) {
+    fs.cpSync(realCopilotHome, tempCopilotHome, { recursive: true });
+  }
+
+  const configPath = path.join(tempCopilotHome, "mcp-config.json");
+  const baseConfig = safeReadJson(configPath) || { mcpServers: {} };
+  const mergedServers = { ...(baseConfig.mcpServers || {}) };
+
+  for (const server of Array.isArray(mcpServers) ? mcpServers : []) {
+    const mapped = mapMcpServerToCopilotConfig(server);
+    if (!mapped) continue;
+    mergedServers[server.name] = mapped;
+  }
+
+  fs.writeFileSync(
+    configPath,
+    JSON.stringify({ ...baseConfig, mcpServers: mergedServers }, null, 2),
+    { mode: 0o600 },
+  );
+
+  return {
+    copilotHome: tempCopilotHome,
+    configPath,
+    serverNames: Object.keys(mergedServers),
+  };
+}
+
 /**
  * Make a streaming HTTP request and forward SSE events back to renderer
  */
@@ -1253,6 +1394,15 @@ function registerHandlers(ipcMain) {
         args: ["exec", "--full-auto", "--json", "{prompt}"],
         resolveAcp: resolveCodexAcpBinaryPath,
       },
+      {
+        command: "copilot",
+        name: "GitHub Copilot CLI",
+        icon: "copilot",
+        description: "GitHub's coding agent CLI",
+        acpCommand: "copilot",
+        acpArgs: ["--acp", "--stdio"],
+        args: ["-p", "{prompt}"],
+      },
     ];
 
     const shellEnv = await getShellEnv();
@@ -1309,6 +1459,7 @@ function registerHandlers(ipcMain) {
       const { resolveAcp: _unused, ...agentInfo } = agent;
       agents.push({
         ...agentInfo,
+        acpCommand: agent.command === "copilot" ? resolvedPath : agentInfo.acpCommand,
         path: resolvedPath,
         version,
         available: true,
@@ -1327,7 +1478,9 @@ function registerHandlers(ipcMain) {
 
     if (customPath) {
       // Normalize Windows shim paths like `codex` -> `codex.cmd` when present.
-      resolvedPath = normalizeCliPathForPlatform(customPath);
+      // Fall back to PATH search if the stored path no longer exists
+      // (e.g. CLI reinstalled to a different location).
+      resolvedPath = normalizeCliPathForPlatform(customPath) || resolveCliFromPath(command, shellEnv);
     } else {
       resolvedPath = resolveCliFromPath(command, shellEnv);
     }
@@ -1521,6 +1674,7 @@ function registerHandlers(ipcMain) {
   const ALLOWED_AGENT_COMMANDS = new Set([
     "claude", "claude-agent-acp",
     "codex", "codex-acp",
+    "copilot",
   ]);
 
   // Spawn an external agent process
@@ -1730,6 +1884,102 @@ function registerHandlers(ipcMain) {
 
   // ── ACP (Agent Client Protocol) streaming ──
 
+  ipcMain.handle("netcatty:ai:acp:list-models", async (event, { acpCommand, acpArgs, cwd, providerId, chatSessionId }) => {
+    if (!validateSender(event)) {
+      return { ok: false, error: "Unauthorized IPC sender" };
+    }
+
+    let provider = null;
+    let copilotConfigInfo = null;
+    try {
+      const { createACPProvider } = require("@mcpc-tech/acp-ai-provider");
+      const shellEnv = await getShellEnv();
+      const sessionCwd = cwd || process.cwd();
+      const isCodexAgent = matchesAgentCommand(acpCommand, "codex-acp");
+      const isClaudeAgent = matchesAgentCommand(acpCommand, "claude-agent-acp");
+      const isCopilotAgent = matchesAgentCommand(acpCommand, "copilot");
+      const agentLabel = isCodexAgent ? "codex" : isClaudeAgent ? "claude" : isCopilotAgent ? "copilot" : acpCommand;
+
+      const resolvedProvider = providerId ? resolveProviderApiKey(providerId) : null;
+      const apiKey = resolvedProvider?.apiKey || undefined;
+
+      const agentEnv = { ...shellEnv };
+      if (apiKey) {
+        agentEnv.CODEX_API_KEY = apiKey;
+      }
+
+      if (isCopilotAgent) {
+        copilotConfigInfo = prepareCopilotHome(shellEnv, [], chatSessionId || `models_${Date.now()}`);
+        agentEnv.COPILOT_HOME = copilotConfigInfo.copilotHome;
+      }
+
+      const claudeAcp = isClaudeAgent ? resolveClaudeAcpBinaryPath(shellEnv, electronModule) : null;
+      const resolvedCommand = isCodexAgent
+        ? resolveCodexAcpBinaryPath(shellEnv, electronModule)
+        : claudeAcp
+          ? claudeAcp.command
+          : acpCommand;
+      const resolvedArgs = claudeAcp
+        ? [...claudeAcp.prependArgs, ...(acpArgs || [])]
+        : acpArgs || [];
+
+      provider = createACPProvider({
+        command: resolvedCommand,
+        args: resolvedArgs,
+        env: agentEnv,
+        session: {
+          cwd: sessionCwd,
+          mcpServers: [],
+        },
+        ...(isCodexAgent
+          ? { authMethodId: apiKey ? "codex-api-key" : "chatgpt" }
+          : isCopilotAgent
+            ? { authMethodId: "copilot-login" }
+            : {}),
+      });
+
+      const sessionInfo = await provider.initSession();
+      const availableModels = Array.isArray(sessionInfo?.models?.availableModels)
+        ? sessionInfo.models.availableModels
+        : [];
+
+      if (isCopilotAgent) {
+        logAcpDebug(agentLabel, "Fetched session models", {
+          chatSessionId: chatSessionId || null,
+          currentModelId: sessionInfo?.models?.currentModelId || null,
+          availableModelIds: availableModels.map((modelInfo) => modelInfo?.modelId).filter(Boolean),
+          copilotHome: copilotConfigInfo?.copilotHome || null,
+          copilotMcpConfigPath: copilotConfigInfo?.configPath || null,
+        });
+      }
+
+      return {
+        ok: true,
+        currentModelId: sessionInfo?.models?.currentModelId || null,
+        models: availableModels.map((modelInfo) => ({
+          id: modelInfo?.modelId,
+          name: modelInfo?.name || modelInfo?.displayName || modelInfo?.modelId,
+          description: modelInfo?.description || undefined,
+        })).filter((modelInfo) => Boolean(modelInfo.id)),
+      };
+    } catch (err) {
+      console.error("[ACP] Failed to list models:", err?.message || err);
+      return { ok: false, error: err?.message || String(err) };
+    } finally {
+      try {
+        cleanupAcpProviderInstance(provider, chatSessionId || "transient-model-list");
+      } catch {
+        // Ignore cleanup failures for transient model-discovery providers.
+      }
+      // Clean up transient COPILOT_HOME created for model listing
+      if (copilotConfigInfo?.copilotHome) {
+        try {
+          fs.rmSync(copilotConfigInfo.copilotHome, { recursive: true, force: true });
+        } catch { /* best-effort */ }
+      }
+    }
+  });
+
   ipcMain.handle("netcatty:ai:acp:stream", async (event, { requestId, chatSessionId, acpCommand, acpArgs, prompt, cwd, providerId, model, existingSessionId, historyMessages, images }) => {
     // Validate IPC sender (Issue #17)
     if (!validateSender(event)) {
@@ -1771,8 +2021,10 @@ function registerHandlers(ipcMain) {
       const shellEnv = await getShellEnv();
       if (shouldAbortStartup()) return { ok: true };
       const sessionCwd = cwd || process.cwd();
-      const isCodexAgent = acpCommand === "codex-acp";
-      const isClaudeAgent = acpCommand === "claude-agent-acp";
+      const isCodexAgent = matchesAgentCommand(acpCommand, "codex-acp");
+      const isClaudeAgent = matchesAgentCommand(acpCommand, "claude-agent-acp");
+      const isCopilotAgent = matchesAgentCommand(acpCommand, "copilot");
+      const agentLabel = isCodexAgent ? "codex" : isClaudeAgent ? "claude" : isCopilotAgent ? "copilot" : acpCommand;
 
       // Resolve API key from providerId (decrypted in main process only)
       const resolvedProvider = providerId ? resolveProviderApiKey(providerId) : null;
@@ -1811,6 +2063,13 @@ function registerHandlers(ipcMain) {
         const scopedIds = mcpServerBridge.getScopedSessionIds(chatSessionId);
         const netcattyMcpConfig = mcpServerBridge.buildMcpServerConfig(mcpPort, scopedIds, chatSessionId);
         mcpSnapshot.mcpServers.push(netcattyMcpConfig);
+        if (isCopilotAgent) {
+          logAcpDebug(agentLabel, "Injected Netcatty MCP server into session", {
+            chatSessionId,
+            scopedIds,
+            injectedServer: summarizeMcpServersForDebug([netcattyMcpConfig])[0],
+          });
+        }
       } catch (err) {
         console.error("[ACP] Failed to inject Netcatty MCP server:", err?.message || err);
       }
@@ -1821,9 +2080,7 @@ function registerHandlers(ipcMain) {
 
       const currentPermissionMode = mcpServerBridge.getPermissionMode();
       let providerEntry = acpProviders.get(chatSessionId);
-      const shouldForceProviderReset = acpForceProviderReset.has(chatSessionId);
       const shouldReuseProvider = Boolean(
-        !shouldForceProviderReset &&
         providerEntry &&
         providerEntry.acpCommand === acpCommand &&
         providerEntry.cwd === sessionCwd &&
@@ -1840,6 +2097,11 @@ function registerHandlers(ipcMain) {
         if (apiKey) {
           agentEnv.CODEX_API_KEY = apiKey;
         }
+        let copilotConfigInfo = null;
+        if (isCopilotAgent) {
+          copilotConfigInfo = prepareCopilotHome(shellEnv, mcpSnapshot.mcpServers, chatSessionId);
+          agentEnv.COPILOT_HOME = copilotConfigInfo.copilotHome;
+        }
 
         const claudeAcp = isClaudeAgent ? resolveClaudeAcpBinaryPath(shellEnv, electronModule) : null;
         const resolvedCommand = isCodexAgent
@@ -1850,6 +2112,7 @@ function registerHandlers(ipcMain) {
         const resolvedArgs = claudeAcp
           ? [...claudeAcp.prependArgs, ...(acpArgs || [])]
           : acpArgs || [];
+        const sessionMcpServers = isCopilotAgent ? [] : mcpSnapshot.mcpServers;
 
         const provider = createACPProvider({
           command: resolvedCommand,
@@ -1857,15 +2120,31 @@ function registerHandlers(ipcMain) {
           env: agentEnv,
           session: {
             cwd: sessionCwd,
-            mcpServers: mcpSnapshot.mcpServers,
+            mcpServers: sessionMcpServers,
           },
           ...(resumeSessionId ? { existingSessionId: resumeSessionId } : {}),
           ...(isCodexAgent
             ? { authMethodId: apiKey ? "codex-api-key" : "chatgpt" }
+            : isCopilotAgent
+              ? { authMethodId: "copilot-login" }
             : {}),
           persistSession: true,
         });
 
+        if (isCopilotAgent) {
+          logAcpDebug(agentLabel, "Creating ACP provider", {
+            requestId,
+            chatSessionId,
+            cwd: sessionCwd,
+            resolvedCommand,
+            resolvedArgs,
+            sessionMcpServers: summarizeMcpServersForDebug(sessionMcpServers),
+            copilotHome: copilotConfigInfo?.copilotHome || null,
+            copilotMcpConfigPath: copilotConfigInfo?.configPath || null,
+            copilotMcpServerNames: copilotConfigInfo?.serverNames || [],
+          });
+        }
+
         providerEntry = {
           provider,
           acpCommand,
@@ -1877,15 +2156,21 @@ function registerHandlers(ipcMain) {
         };
         acpProviders.set(chatSessionId, providerEntry);
       }
-      acpForceProviderReset.delete(chatSessionId);
-
       let modelInstance = providerEntry.provider.languageModel(model || undefined);
       try {
         await providerEntry.provider.initSession(providerEntry.provider.tools);
+        if (isCopilotAgent) {
+          logAcpDebug(agentLabel, "ACP session initialized", {
+            requestId,
+            chatSessionId,
+            providerSessionId: providerEntry.provider.getSessionId?.() || null,
+            toolNames: Object.keys(providerEntry.provider.tools || {}),
+          });
+        }
         if (shouldAbortStartup()) return { ok: true };
       } catch (err) {
         const attemptedResumeSessionId = providerEntry.provider?.getSessionId?.() || existingSessionId;
-        if (!attemptedResumeSessionId || !isUnsupportedLoadSessionError(err)) {
+        if (!attemptedResumeSessionId || !shouldRetryFreshSession(err)) {
           throw err;
         }
 
@@ -1901,13 +2186,22 @@ function registerHandlers(ipcMain) {
           args: fallbackClaudeAcp
             ? [...fallbackClaudeAcp.prependArgs, ...(acpArgs || [])]
             : acpArgs || [],
-          env: apiKey ? { ...shellEnv, CODEX_API_KEY: apiKey } : { ...shellEnv },
+          env: (() => {
+            const fallbackEnv = apiKey ? { ...shellEnv, CODEX_API_KEY: apiKey } : { ...shellEnv };
+            if (isCopilotAgent) {
+              const fallbackCopilotConfig = prepareCopilotHome(shellEnv, mcpSnapshot.mcpServers, chatSessionId);
+              fallbackEnv.COPILOT_HOME = fallbackCopilotConfig.copilotHome;
+            }
+            return fallbackEnv;
+          })(),
           session: {
             cwd: sessionCwd,
-            mcpServers: mcpSnapshot.mcpServers,
+            mcpServers: isCopilotAgent ? [] : mcpSnapshot.mcpServers,
           },
           ...(isCodexAgent
             ? { authMethodId: apiKey ? "codex-api-key" : "chatgpt" }
+            : isCopilotAgent
+              ? { authMethodId: "copilot-login" }
             : {}),
           persistSession: true,
         });
@@ -1924,6 +2218,14 @@ function registerHandlers(ipcMain) {
         acpProviders.set(chatSessionId, providerEntry);
         modelInstance = providerEntry.provider.languageModel(model || undefined);
         await providerEntry.provider.initSession(providerEntry.provider.tools);
+        if (isCopilotAgent) {
+          logAcpDebug(agentLabel, "ACP session initialized after fallback", {
+            requestId,
+            chatSessionId,
+            providerSessionId: providerEntry.provider.getSessionId?.() || null,
+            toolNames: Object.keys(providerEntry.provider.tools || {}),
+          });
+        }
         if (shouldAbortStartup()) return { ok: true };
       }
       const activeProviderSessionId = providerEntry.provider.getSessionId?.() || null;
@@ -2042,6 +2344,9 @@ function registerHandlers(ipcMain) {
             if (serialized.type === "text-delta" || serialized.type === "reasoning-delta" || serialized.type === "tool-call") {
               hasContent = true;
             }
+            if (isCopilotAgent && (serialized.type === "tool-call" || serialized.type === "tool-result" || serialized.type === "error" || serialized.type === "status")) {
+              logAcpDebug(agentLabel, `Stream event: ${serialized.type}`, serialized);
+            }
             safeSend(event.sender, "netcatty:ai:acp:event", {
               requestId,
               event: serialized,
@@ -2057,6 +2362,13 @@ function registerHandlers(ipcMain) {
 
       // If stream completed with zero content, likely an auth or connection issue
       if (!hasContent && !abortController.signal.aborted) {
+        if (isCopilotAgent) {
+          logAcpDebug(agentLabel, "Stream completed with no content", {
+            requestId,
+            chatSessionId,
+            providerSessionId: providerEntry.provider.getSessionId?.() || null,
+          });
+        }
         if (!isActiveAcpRun(chatSessionId, requestId)) {
           return { ok: true };
         }
@@ -2095,9 +2407,6 @@ function registerHandlers(ipcMain) {
       acpPendingCancelRequests.delete(requestId);
       const activeRun = acpChatRuns.get(chatSessionId);
       if (activeRun?.requestId === requestId) {
-        if (abortController?.signal?.aborted || activeRun.cancelRequested) {
-          cleanupAcpProvider(chatSessionId);
-        }
         acpChatRuns.delete(chatSessionId);
       }
     }
@@ -2127,10 +2436,6 @@ function registerHandlers(ipcMain) {
       acpPendingCancelRequests.add(effectiveRequestId);
       cancelled = true;
     }
-    if (effectiveChatSessionId) {
-      acpForceProviderReset.add(effectiveChatSessionId);
-      cleanupAcpProvider(effectiveChatSessionId);
-    }
     // Preserve the ACP provider session on stop so the next user message can
     // continue within the same persisted conversation context. Full provider
     // cleanup is handled by netcatty:ai:acp:cleanup when the chat is deleted.
@@ -2143,7 +2448,6 @@ function registerHandlers(ipcMain) {
   ipcMain.handle("netcatty:ai:acp:cleanup", async (event, { chatSessionId }) => {
     if (!validateSender(event)) return { ok: false, error: "Unauthorized IPC sender" };
     mcpServerBridge.setChatSessionCancelled?.(chatSessionId, true);
-    acpForceProviderReset.delete(chatSessionId);
     cleanupAcpProvider(chatSessionId);
     mcpServerBridge.cleanupScopedMetadata(chatSessionId);
     return { ok: true };

electron/bridges/mcpServerBridge.cjs

@@ -380,6 +380,7 @@ async function handleMessage(socket, line) {
       if (!socket.destroyed) socket.write(response);
       return;
     }
+    console.warn("[MCP Bridge] auth/verify failed or unexpected first method", method);
     // Wrong token or wrong method — reject and close
     const response = JSON.stringify({
       jsonrpc: "2.0",
@@ -629,6 +630,22 @@ function handleExec(params) {
 
 // ── MCP Server Config Builder ──
 
+function resolveMcpServerRuntimeCommand() {
+  const runtimeCommand = process.execPath;
+  const runtimeEnv = [];
+
+  if (runtimeCommand && existsSync(runtimeCommand)) {
+    const basename = path.basename(runtimeCommand).toLowerCase();
+    const isNodeBinary = basename === "node" || basename.startsWith("node.");
+    if (!isNodeBinary) {
+      runtimeEnv.push({ name: "ELECTRON_RUN_AS_NODE", value: "1" });
+    }
+    return { command: runtimeCommand, env: runtimeEnv };
+  }
+
+  return { command: "node", env: runtimeEnv };
+}
+
 function buildMcpServerConfig(port, scopedSessionIds, chatSessionId) {
   // Use provided scoped IDs, or resolve from chatSessionId, or fall back
   const effectiveIds = (scopedSessionIds && scopedSessionIds.length > 0)
@@ -638,8 +655,10 @@ function buildMcpServerConfig(port, scopedSessionIds, chatSessionId) {
   const runtimePath = toUnpackedAsarPath(
     path.join(__dirname, "..", "mcp", "netcatty-mcp-server.cjs"),
   );
+  const runtime = resolveMcpServerRuntimeCommand();
 
   const env = [
+    ...runtime.env,
     { name: "NETCATTY_MCP_PORT", value: String(port) },
   ];
 
@@ -664,7 +683,7 @@ function buildMcpServerConfig(port, scopedSessionIds, chatSessionId) {
   return {
     name: "netcatty-remote-hosts",
     type: "stdio",
-    command: "node",
+    command: runtime.command,
     args: [runtimePath],
     env,
   };

electron/preload.cjs

@@ -1207,6 +1207,9 @@ const api = {
   aiAcpStream: async (requestId, chatSessionId, acpCommand, acpArgs, prompt, cwd, providerId, model, existingSessionId, historyMessages, images) => {
     return ipcRenderer.invoke("netcatty:ai:acp:stream", { requestId, chatSessionId, acpCommand, acpArgs, prompt, cwd, providerId, model, existingSessionId, historyMessages, images });
   },
+  aiAcpListModels: async (acpCommand, acpArgs, cwd, providerId, chatSessionId) => {
+    return ipcRenderer.invoke("netcatty:ai:acp:list-models", { acpCommand, acpArgs, cwd, providerId, chatSessionId });
+  },
   aiAcpCancel: async (requestId, chatSessionId) => {
     return ipcRenderer.invoke("netcatty:ai:acp:cancel", { requestId, chatSessionId });
   },

infrastructure/ai/managedAgents.ts

@@ -0,0 +1,69 @@
+import type { DiscoveredAgent, ExternalAgentConfig } from './types';
+
+export type ManagedAgentKey = 'codex' | 'claude' | 'copilot';
+
+const MANAGED_AGENT_META: Record<ManagedAgentKey, { commandNames: string[]; acpCommand: string }> = {
+  codex: { commandNames: ['codex', 'codex-acp'], acpCommand: 'codex-acp' },
+  claude: { commandNames: ['claude', 'claude-agent-acp'], acpCommand: 'claude-agent-acp' },
+  copilot: { commandNames: ['copilot'], acpCommand: 'copilot' },
+};
+
+function getCommandBasename(command: string | undefined): string {
+  const normalized = String(command || '').trim();
+  if (!normalized) return '';
+  const parts = normalized.split(/[\\/]/);
+  return (parts.pop() || '').toLowerCase();
+}
+
+function isPathLikeCommand(command: string | undefined): boolean {
+  const normalized = String(command || '').trim();
+  return normalized.includes('/') || normalized.includes('\\');
+}
+
+function matchesPrimaryCliBasename(command: string | undefined, agentKey: ManagedAgentKey): boolean {
+  const basename = getCommandBasename(command);
+  return basename === agentKey || basename.startsWith(`${agentKey}.`);
+}
+
+export function isSettingsManagedDiscoveredAgent(
+  agent: Pick<DiscoveredAgent, 'command'>,
+): agent is Pick<DiscoveredAgent, 'command'> & { command: ManagedAgentKey } {
+  return agent.command === 'codex' || agent.command === 'claude' || agent.command === 'copilot';
+}
+
+export function matchesManagedAgentConfig(
+  agent: Pick<ExternalAgentConfig, 'id' | 'command' | 'acpCommand'>,
+  agentKey: ManagedAgentKey,
+): boolean {
+  const meta = MANAGED_AGENT_META[agentKey];
+  const basename = getCommandBasename(agent.command);
+  return (
+    agent.id === `discovered_${agentKey}` ||
+    agent.acpCommand === meta.acpCommand ||
+    meta.commandNames.some((commandName) => basename === commandName || basename.startsWith(`${commandName}.`))
+  );
+}
+
+export function getManagedAgentStoredPath(
+  agents: ExternalAgentConfig[],
+  agentKey: ManagedAgentKey,
+): string | null {
+  const managedId = `discovered_${agentKey}`;
+  const preferredAgent = agents.find(
+    (agent) =>
+      agent.id === managedId &&
+      isPathLikeCommand(agent.command) &&
+      matchesPrimaryCliBasename(agent.command, agentKey),
+  );
+  if (preferredAgent) {
+    return preferredAgent.command;
+  }
+
+  const fallbackAgent = agents.find(
+    (agent) =>
+      matchesManagedAgentConfig(agent, agentKey) &&
+      isPathLikeCommand(agent.command) &&
+      matchesPrimaryCliBasename(agent.command, agentKey),
+  );
+  return fallbackAgent?.command ?? null;
+}

public/ai/agents/copilot.svg

@@ -0,0 +1 @@
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