Merge pull request #1322 from QwenLM/mingholy/feat/headless-slash-commands

feat: support /compress and /summary commands for non-interactive & ACP

docs/users/configuration/settings.md

@@ -124,38 +124,12 @@ Settings are organized into categories. All settings should be placed within the
         "temperature": 0.2,
         "top_p": 0.8,
         "max_tokens": 1024
-      },
-      "reasoning": {
-        "effort": "medium"
       }
     }
   }
 }
 ```
 
-**Reasoning Configuration:**
-
-The `reasoning` field controls reasoning behavior for models that support it:
-
-- Set to `false` to disable reasoning entirely
-- Set to an object with `effort` field to enable reasoning with a specific effort level:
-  - `"low"`: Minimal reasoning effort
-  - `"medium"`: Balanced reasoning effort (default)
-  - `"high"`: Maximum reasoning effort
-- Optionally include `budget_tokens` to limit reasoning token usage
-
-Example to disable reasoning:
-
-```json
-{
-  "model": {
-    "generationConfig": {
-      "reasoning": false
-    }
-  }
-}
-```
-
 **model.openAILoggingDir examples:**
 
 - `"~/qwen-logs"` - Logs to `~/qwen-logs` directory

integration-tests/sdk-typescript/system-control.test.ts

@@ -314,4 +314,88 @@ describe('System Control (E2E)', () => {
       );
     });
   });
+
+  describe('supportedCommands API', () => {
+    it('should return list of supported slash commands', async () => {
+      const sessionId = crypto.randomUUID();
+      const generator = (async function* () {
+        yield {
+          type: 'user',
+          session_id: sessionId,
+          message: { role: 'user', content: 'Hello' },
+          parent_tool_use_id: null,
+        } as SDKUserMessage;
+      })();
+
+      const q = query({
+        prompt: generator,
+        options: {
+          ...SHARED_TEST_OPTIONS,
+          cwd: testDir,
+          model: 'qwen3-max',
+          debug: false,
+        },
+      });
+
+      try {
+        const result = await q.supportedCommands();
+        // Start consuming messages to trigger initialization
+        const messageConsumer = (async () => {
+          try {
+            for await (const _message of q) {
+              // Just consume messages
+            }
+          } catch (error) {
+            // Ignore errors from query being closed
+            if (error instanceof Error && error.message !== 'Query is closed') {
+              throw error;
+            }
+          }
+        })();
+
+        // Verify result structure
+        expect(result).toBeDefined();
+        expect(result).toHaveProperty('commands');
+        expect(Array.isArray(result?.['commands'])).toBe(true);
+
+        const commands = result?.['commands'] as string[];
+
+        // Verify default allowed built-in commands are present
+        expect(commands).toContain('init');
+        expect(commands).toContain('summary');
+        expect(commands).toContain('compress');
+
+        // Verify commands are sorted
+        const sortedCommands = [...commands].sort();
+        expect(commands).toEqual(sortedCommands);
+
+        // Verify all commands are strings
+        commands.forEach((cmd) => {
+          expect(typeof cmd).toBe('string');
+          expect(cmd.length).toBeGreaterThan(0);
+        });
+
+        await q.close();
+        await messageConsumer;
+      } catch (error) {
+        await q.close();
+        throw error;
+      }
+    });
+
+    it('should throw error when supportedCommands is called on closed query', async () => {
+      const q = query({
+        prompt: 'Hello',
+        options: {
+          ...SHARED_TEST_OPTIONS,
+          cwd: testDir,
+          model: 'qwen3-max',
+        },
+      });
+
+      await q.close();
+
+      await expect(q.supportedCommands()).rejects.toThrow('Query is closed');
+    });
+  });
 });

packages/cli/src/acp-integration/acp.ts

@@ -98,6 +98,14 @@ export class AgentSideConnection implements Client {
     );
   }
 
+  /**
+   * Sends a custom notification to the client.
+   * Used for extension-specific notifications that are not part of the core ACP protocol.
+   */
+  async sendCustomNotification<T>(method: string, params: T): Promise<void> {
+    return await this.#connection.sendNotification(method, params);
+  }
+
   /**
    * Request permission before running a tool
    *
@@ -374,6 +382,7 @@ export interface Client {
   ): Promise<schema.RequestPermissionResponse>;
   sessionUpdate(params: schema.SessionNotification): Promise<void>;
   authenticateUpdate(params: schema.AuthenticateUpdate): Promise<void>;
+  sendCustomNotification<T>(method: string, params: T): Promise<void>;
   writeTextFile(
     params: schema.WriteTextFileRequest,
   ): Promise<schema.WriteTextFileResponse>;

packages/cli/src/acp-integration/acpAgent.ts

@@ -15,7 +15,6 @@ import {
   qwenOAuth2Events,
   MCPServerConfig,
   SessionService,
-  buildApiHistoryFromConversation,
   type Config,
   type ConversationRecord,
   type DeviceAuthorizationData,
@@ -349,12 +348,20 @@ class GeminiAgent {
     const sessionId = config.getSessionId();
     const geminiClient = config.getGeminiClient();
 
-    const history = conversation
-      ? buildApiHistoryFromConversation(conversation)
-      : undefined;
-    const chat = history
-      ? await geminiClient.startChat(history)
-      : await geminiClient.startChat();
+    // Use GeminiClient to manage chat lifecycle properly
+    // This ensures geminiClient.chat is in sync with the session's chat
+    //
+    // Note: When loading a session, config.initialize() has already been called
+    // in newSessionConfig(), which in turn calls geminiClient.initialize().
+    // The GeminiClient.initialize() method checks config.getResumedSessionData()
+    // and automatically loads the conversation history into the chat instance.
+    // So we only need to initialize if it hasn't been done yet.
+    if (!geminiClient.isInitialized()) {
+      await geminiClient.initialize();
+    }
+
+    // Now get the chat instance that's managed by GeminiClient
+    const chat = geminiClient.getChat();
 
     const session = new Session(
       sessionId,

packages/cli/src/acp-integration/session/Session.ts

@@ -41,9 +41,11 @@ import * as fs from 'node:fs/promises';
 import * as path from 'node:path';
 import { z } from 'zod';
 import { getErrorMessage } from '../../utils/errors.js';
+import { normalizePartList } from '../../utils/nonInteractiveHelpers.js';
 import {
   handleSlashCommand,
   getAvailableCommands,
+  type NonInteractiveSlashCommandResult,
 } from '../../nonInteractiveCliCommands.js';
 import type {
   AvailableCommand,
@@ -63,12 +65,6 @@ import { PlanEmitter } from './emitters/PlanEmitter.js';
 import { MessageEmitter } from './emitters/MessageEmitter.js';
 import { SubAgentTracker } from './SubAgentTracker.js';
 
-/**
- * Built-in commands that are allowed in ACP integration mode.
- * Only safe, read-only commands that don't require interactive UI.
- */
-export const ALLOWED_BUILTIN_COMMANDS_FOR_ACP = ['init'];
-
 /**
  * Session represents an active conversation session with the AI model.
  * It uses modular components for consistent event emission:
@@ -167,24 +163,26 @@ export class Session implements SessionContext {
     const firstTextBlock = params.prompt.find((block) => block.type === 'text');
     const inputText = firstTextBlock?.text || '';
 
-    let parts: Part[];
+    let parts: Part[] | null;
 
     if (isSlashCommand(inputText)) {
-      // Handle slash command - allow specific built-in commands for ACP integration
+      // Handle slash command - uses default allowed commands (init, summary, compress)
       const slashCommandResult = await handleSlashCommand(
         inputText,
         pendingSend,
         this.config,
         this.settings,
-        ALLOWED_BUILTIN_COMMANDS_FOR_ACP,
       );
 
-      if (slashCommandResult) {
-        // Use the result from the slash command
-        parts = slashCommandResult as Part[];
-      } else {
-        // Slash command didn't return a prompt, continue with normal processing
-        parts = await this.#resolvePrompt(params.prompt, pendingSend.signal);
+      parts = await this.#processSlashCommandResult(
+        slashCommandResult,
+        params.prompt,
+      );
+
+      // If parts is null, the command was fully handled (e.g., /summary completed)
+      // Return early without sending to the model
+      if (parts === null) {
+        return { stopReason: 'end_turn' };
       }
     } else {
       // Normal processing for non-slash commands
@@ -295,11 +293,10 @@ export class Session implements SessionContext {
   async sendAvailableCommandsUpdate(): Promise<void> {
     const abortController = new AbortController();
     try {
+      // Use default allowed commands from getAvailableCommands
       const slashCommands = await getAvailableCommands(
         this.config,
-        this.settings,
         abortController.signal,
-        ALLOWED_BUILTIN_COMMANDS_FOR_ACP,
       );
 
       // Convert SlashCommand[] to AvailableCommand[] format for ACP protocol
@@ -647,6 +644,103 @@ export class Session implements SessionContext {
     }
   }
 
+  /**
+   * Processes the result of a slash command execution.
+   *
+   * Supported result types in ACP mode:
+   * - submit_prompt: Submits content to the model
+   * - stream_messages: Streams multiple messages to the client (ACP-specific)
+   * - unsupported: Command cannot be executed in ACP mode
+   * - no_command: No command was found, use original prompt
+   *
+   * Note: 'message' type is not supported in ACP mode - commands should use
+   * 'stream_messages' instead for consistent async handling.
+   *
+   * @param result The result from handleSlashCommand
+   * @param originalPrompt The original prompt blocks
+   * @returns Parts to use for the prompt, or null if command was handled without needing model interaction
+   */
+  async #processSlashCommandResult(
+    result: NonInteractiveSlashCommandResult,
+    originalPrompt: acp.ContentBlock[],
+  ): Promise<Part[] | null> {
+    switch (result.type) {
+      case 'submit_prompt':
+        // Command wants to submit a prompt to the model
+        // Convert PartListUnion to Part[]
+        return normalizePartList(result.content);
+
+      case 'message': {
+        // 'message' type is not ideal for ACP mode, but we handle it for compatibility
+        // by converting it to a stream_messages-like notification
+        await this.client.sendCustomNotification('_qwencode/slash_command', {
+          sessionId: this.sessionId,
+          command: originalPrompt
+            .filter((block) => block.type === 'text')
+            .map((block) => (block.type === 'text' ? block.text : ''))
+            .join(' '),
+          messageType: result.messageType,
+          message: result.content || '',
+        });
+
+        if (result.messageType === 'error') {
+          // Throw error to stop execution
+          throw new Error(result.content || 'Slash command failed.');
+        }
+        // For info messages, return null to indicate command was handled
+        return null;
+      }
+
+      case 'stream_messages': {
+        // Command returns multiple messages via async generator (ACP-preferred)
+        const command = originalPrompt
+          .filter((block) => block.type === 'text')
+          .map((block) => (block.type === 'text' ? block.text : ''))
+          .join(' ');
+
+        // Stream all messages to the client
+        for await (const msg of result.messages) {
+          await this.client.sendCustomNotification('_qwencode/slash_command', {
+            sessionId: this.sessionId,
+            command,
+            messageType: msg.messageType,
+            message: msg.content,
+          });
+
+          // If we encounter an error message, throw after sending
+          if (msg.messageType === 'error') {
+            throw new Error(msg.content || 'Slash command failed.');
+          }
+        }
+
+        // All messages sent successfully, return null to indicate command was handled
+        return null;
+      }
+
+      case 'unsupported': {
+        // Command returned an unsupported result type
+        const unsupportedError = `Slash command not supported in ACP integration: ${result.reason}`;
+        throw new Error(unsupportedError);
+      }
+
+      case 'no_command':
+        // No command was found or executed, use original prompt
+        return originalPrompt.map((block) => {
+          if (block.type === 'text') {
+            return { text: block.text };
+          }
+          throw new Error(`Unsupported block type: ${block.type}`);
+        });
+
+      default: {
+        // Exhaustiveness check
+        const _exhaustive: never = result;
+        const unknownError = `Unknown slash command result type: ${(_exhaustive as NonInteractiveSlashCommandResult).type}`;
+        throw new Error(unknownError);
+      }
+    }
+  }
+
   async #resolvePrompt(
     message: acp.ContentBlock[],
     abortSignal: AbortSignal,

packages/cli/src/config/settingsSchema.ts

@@ -675,45 +675,6 @@ const SETTINGS_SCHEMA = {
               { value: 'openapi_30', label: 'OpenAPI 3.0 Strict' },
             ],
           },
-          samplingParams: {
-            type: 'object',
-            label: 'Sampling Parameters',
-            category: 'Generation Configuration',
-            requiresRestart: false,
-            default: undefined as
-              | {
-                  top_p?: number;
-                  top_k?: number;
-                  repetition_penalty?: number;
-                  presence_penalty?: number;
-                  frequency_penalty?: number;
-                  temperature?: number;
-                  max_tokens?: number;
-                }
-              | undefined,
-            description: 'Sampling parameters for content generation.',
-            parentKey: 'generationConfig',
-            childKey: 'samplingParams',
-            showInDialog: false,
-          },
-          reasoning: {
-            type: 'object',
-            label: 'Reasoning Configuration',
-            category: 'Generation Configuration',
-            requiresRestart: false,
-            default: undefined as
-              | false
-              | {
-                  effort?: 'low' | 'medium' | 'high';
-                  budget_tokens?: number;
-                }
-              | undefined,
-            description:
-              'Reasoning configuration for models that support reasoning. Set to false to disable reasoning, or provide an object with effort level and optional token budget.',
-            parentKey: 'generationConfig',
-            childKey: 'reasoning',
-            showInDialog: false,
-          },
         },
       },
     },

packages/cli/src/i18n/locales/en.js

@@ -258,6 +258,8 @@ export default {
   ', Tab to change focus': ', Tab to change focus',
   'To see changes, Qwen Code must be restarted. Press r to exit and apply changes now.':
     'To see changes, Qwen Code must be restarted. Press r to exit and apply changes now.',
+  'The command "/{{command}}" is not supported in non-interactive mode.':
+    'The command "/{{command}}" is not supported in non-interactive mode.',
   // ============================================================================
   // Settings Labels
   // ============================================================================
@@ -590,6 +592,12 @@ export default {
   'No conversation found to summarize.': 'No conversation found to summarize.',
   'Failed to generate project context summary: {{error}}':
     'Failed to generate project context summary: {{error}}',
+  'Saved project summary to {{filePathForDisplay}}.':
+    'Saved project summary to {{filePathForDisplay}}.',
+  'Saving project summary...': 'Saving project summary...',
+  'Generating project summary...': 'Generating project summary...',
+  'Failed to generate summary - no text content received from LLM response':
+    'Failed to generate summary - no text content received from LLM response',
 
   // ============================================================================
   // Commands - Model

packages/cli/src/i18n/locales/ru.js

@@ -260,7 +260,8 @@ export default {
   ', Tab to change focus': ', Tab для смены фокуса',
   'To see changes, Qwen Code must be restarted. Press r to exit and apply changes now.':
     'Для применения изменений необходимо перезапустить Qwen Code. Нажмите r для выхода и применения изменений.',
-
+  'The command "/{{command}}" is not supported in non-interactive mode.':
+    'Команда "/{{command}}" не поддерживается в неинтерактивном режиме.',
   // ============================================================================
   // Метки настроек
   // ============================================================================
@@ -604,6 +605,12 @@ export default {
     'Не найдено диалогов для создания сводки.',
   'Failed to generate project context summary: {{error}}':
     'Не удалось сгенерировать сводку контекста проекта: {{error}}',
+  'Saved project summary to {{filePathForDisplay}}.':
+    'Сводка проекта сохранена в {{filePathForDisplay}}',
+  'Saving project summary...': 'Сохранение сводки проекта...',
+  'Generating project summary...': 'Генерация сводки проекта...',
+  'Failed to generate summary - no text content received from LLM response':
+    'Не удалось сгенерировать сводку - не получен текстовый контент из ответа LLM',
 
   // ============================================================================
   // Команды - Модель

packages/cli/src/i18n/locales/zh.js

@@ -249,6 +249,8 @@ export default {
   ', Tab to change focus': '，Tab 切换焦点',
   'To see changes, Qwen Code must be restarted. Press r to exit and apply changes now.':
     '要查看更改，必须重启 Qwen Code。按 r 退出并立即应用更改。',
+  'The command "/{{command}}" is not supported in non-interactive mode.':
+    '不支持在非交互模式下使用命令 "/{{command}}"。',
   // ============================================================================
   // Settings Labels
   // ============================================================================
@@ -560,6 +562,12 @@ export default {
   'No conversation found to summarize.': '未找到要总结的对话',
   'Failed to generate project context summary: {{error}}':
     '生成项目上下文摘要失败：{{error}}',
+  'Saved project summary to {{filePathForDisplay}}.':
+    '项目摘要已保存到 {{filePathForDisplay}}',
+  'Saving project summary...': '正在保存项目摘要...',
+  'Generating project summary...': '正在生成项目摘要...',
+  'Failed to generate summary - no text content received from LLM response':
+    '生成摘要失败 - 未从 LLM 响应中接收到文本内容',
 
   // ============================================================================
   // Commands - Model

packages/cli/src/nonInteractive/control/controllers/systemController.ts

@@ -20,8 +20,7 @@ import type {
   CLIControlSetModelRequest,
   CLIMcpServerConfig,
 } from '../../types.js';
-import { CommandService } from '../../../services/CommandService.js';
-import { BuiltinCommandLoader } from '../../../services/BuiltinCommandLoader.js';
+import { getAvailableCommands } from '../../../nonInteractiveCliCommands.js';
 import {
   MCPServerConfig,
   AuthProviderType,
@@ -407,7 +406,7 @@ export class SystemController extends BaseController {
   }
 
   /**
-   * Load slash command names using CommandService
+   * Load slash command names using getAvailableCommands
    *
    * @param signal - AbortSignal to respect for cancellation
    * @returns Promise resolving to array of slash command names
@@ -418,21 +417,14 @@ export class SystemController extends BaseController {
     }
 
     try {
-      const service = await CommandService.create(
-        [new BuiltinCommandLoader(this.context.config)],
-        signal,
-      );
+      const commands = await getAvailableCommands(this.context.config, signal);
 
       if (signal.aborted) {
         return [];
       }
 
-      const names = new Set<string>();
-      const commands = service.getCommands();
-      for (const command of commands) {
-        names.add(command.name);
-      }
-      return Array.from(names).sort();
+      // Extract command names and sort
+      return commands.map((cmd) => cmd.name).sort();
     } catch (error) {
       // Check if the error is due to abort
       if (signal.aborted) {

packages/cli/src/nonInteractiveCli.test.ts

@@ -68,6 +68,7 @@ describe('runNonInteractive', () => {
   let mockShutdownTelemetry: Mock;
   let consoleErrorSpy: MockInstance;
   let processStdoutSpy: MockInstance;
+  let processStderrSpy: MockInstance;
   let mockGeminiClient: {
     sendMessageStream: Mock;
     getChatRecordingService: Mock;
@@ -86,6 +87,9 @@ describe('runNonInteractive', () => {
     processStdoutSpy = vi
       .spyOn(process.stdout, 'write')
       .mockImplementation(() => true);
+    processStderrSpy = vi
+      .spyOn(process.stderr, 'write')
+      .mockImplementation(() => true);
     vi.spyOn(process, 'exit').mockImplementation((code) => {
       throw new Error(`process.exit(${code}) called`);
     });
@@ -139,6 +143,8 @@ describe('runNonInteractive', () => {
       setModel: vi.fn(async (model: string) => {
         currentModel = model;
       }),
+      getExperimentalZedIntegration: vi.fn().mockReturnValue(false),
+      isInteractive: vi.fn().mockReturnValue(false),
     } as unknown as Config;
 
     mockSettings = {
@@ -852,7 +858,7 @@ describe('runNonInteractive', () => {
     expect(processStdoutSpy).toHaveBeenCalledWith('Response from command');
   });
 
-  it('should throw FatalInputError if a command requires confirmation', async () => {
+  it('should handle command that requires confirmation by returning early', async () => {
     const mockCommand = {
       name: 'confirm',
       description: 'a command that needs confirmation',
@@ -864,15 +870,16 @@ describe('runNonInteractive', () => {
     };
     mockGetCommands.mockReturnValue([mockCommand]);
 
-    await expect(
-      runNonInteractive(
-        mockConfig,
-        mockSettings,
-        '/confirm',
-        'prompt-id-confirm',
-      ),
-    ).rejects.toThrow(
-      'Exiting due to a confirmation prompt requested by the command.',
+    await runNonInteractive(
+      mockConfig,
+      mockSettings,
+      '/confirm',
+      'prompt-id-confirm',
+    );
+
+    // Should write error message to stderr
+    expect(processStderrSpy).toHaveBeenCalledWith(
+      'Shell command confirmation is not supported in non-interactive mode. Use YOLO mode or pre-approve commands.\n',
     );
   });
 
@@ -909,7 +916,30 @@ describe('runNonInteractive', () => {
     expect(processStdoutSpy).toHaveBeenCalledWith('Response to unknown');
   });
 
-  it('should throw for unhandled command result types', async () => {
+  it('should handle known but unsupported slash commands like /help by returning early', async () => {
+    // Mock a built-in command that exists but is not in the allowed list
+    const mockHelpCommand = {
+      name: 'help',
+      description: 'Show help',
+      kind: CommandKind.BUILT_IN,
+      action: vi.fn(),
+    };
+    mockGetCommands.mockReturnValue([mockHelpCommand]);
+
+    await runNonInteractive(
+      mockConfig,
+      mockSettings,
+      '/help',
+      'prompt-id-help',
+    );
+
+    // Should write error message to stderr
+    expect(processStderrSpy).toHaveBeenCalledWith(
+      'The command "/help" is not supported in non-interactive mode.\n',
+    );
+  });
+
+  it('should handle unhandled command result types by returning early with error', async () => {
     const mockCommand = {
       name: 'noaction',
       description: 'unhandled type',
@@ -920,15 +950,16 @@ describe('runNonInteractive', () => {
     };
     mockGetCommands.mockReturnValue([mockCommand]);
 
-    await expect(
-      runNonInteractive(
-        mockConfig,
-        mockSettings,
-        '/noaction',
-        'prompt-id-unhandled',
-      ),
-    ).rejects.toThrow(
-      'Exiting due to command result that is not supported in non-interactive mode.',
+    await runNonInteractive(
+      mockConfig,
+      mockSettings,
+      '/noaction',
+      'prompt-id-unhandled',
+    );
+
+    // Should write error message to stderr
+    expect(processStderrSpy).toHaveBeenCalledWith(
+      'Unknown command result type: unhandled\n',
     );
   });
 

packages/cli/src/nonInteractiveCli.ts

@@ -42,6 +42,55 @@ import {
   computeUsageFromMetrics,
 } from './utils/nonInteractiveHelpers.js';
 
+/**
+ * Emits a final message for slash command results.
+ * Note: systemMessage should already be emitted before calling this function.
+ */
+async function emitNonInteractiveFinalMessage(params: {
+  message: string;
+  isError: boolean;
+  adapter?: JsonOutputAdapterInterface;
+  config: Config;
+  startTimeMs: number;
+}): Promise<void> {
+  const { message, isError, adapter, config } = params;
+
+  if (!adapter) {
+    // Text output mode: write directly to stdout/stderr
+    const target = isError ? process.stderr : process.stdout;
+    target.write(`${message}\n`);
+    return;
+  }
+
+  // JSON output mode: emit assistant message and result
+  // (systemMessage should already be emitted by caller)
+  adapter.startAssistantMessage();
+  adapter.processEvent({
+    type: GeminiEventType.Content,
+    value: message,
+  } as unknown as Parameters<JsonOutputAdapterInterface['processEvent']>[0]);
+  adapter.finalizeAssistantMessage();
+
+  const metrics = uiTelemetryService.getMetrics();
+  const usage = computeUsageFromMetrics(metrics);
+  const outputFormat = config.getOutputFormat();
+  const stats =
+    outputFormat === OutputFormat.JSON
+      ? uiTelemetryService.getMetrics()
+      : undefined;
+
+  adapter.emitResult({
+    isError,
+    durationMs: Date.now() - params.startTimeMs,
+    apiDurationMs: 0,
+    numTurns: 0,
+    errorMessage: isError ? message : undefined,
+    usage,
+    stats,
+    summary: message,
+  });
+}
+
 /**
  * Provides optional overrides for `runNonInteractive` execution.
  *
@@ -115,6 +164,16 @@ export async function runNonInteractive(
       process.on('SIGINT', shutdownHandler);
       process.on('SIGTERM', shutdownHandler);
 
+      // Emit systemMessage first (always the first message in JSON mode)
+      if (adapter) {
+        const systemMessage = await buildSystemMessage(
+          config,
+          sessionId,
+          permissionMode,
+        );
+        adapter.emitMessage(systemMessage);
+      }
+
       let initialPartList: PartListUnion | null = extractPartsFromUserMessage(
         options.userMessage,
       );
@@ -128,10 +187,45 @@ export async function runNonInteractive(
             config,
             settings,
           );
-          if (slashCommandResult) {
-            // A slash command can replace the prompt entirely; fall back to @-command processing otherwise.
-            initialPartList = slashCommandResult as PartListUnion;
-            slashHandled = true;
+          switch (slashCommandResult.type) {
+            case 'submit_prompt':
+              // A slash command can replace the prompt entirely; fall back to @-command processing otherwise.
+              initialPartList = slashCommandResult.content;
+              slashHandled = true;
+              break;
+            case 'message': {
+              // systemMessage already emitted above
+              await emitNonInteractiveFinalMessage({
+                message: slashCommandResult.content,
+                isError: slashCommandResult.messageType === 'error',
+                adapter,
+                config,
+                startTimeMs: startTime,
+              });
+              return;
+            }
+            case 'stream_messages':
+              throw new FatalInputError(
+                'Stream messages mode is not supported in non-interactive CLI',
+              );
+            case 'unsupported': {
+              await emitNonInteractiveFinalMessage({
+                message: slashCommandResult.reason,
+                isError: true,
+                adapter,
+                config,
+                startTimeMs: startTime,
+              });
+              return;
+            }
+            case 'no_command':
+              break;
+            default: {
+              const _exhaustive: never = slashCommandResult;
+              throw new FatalInputError(
+                `Unhandled slash command result type: ${(_exhaustive as { type: string }).type}`,
+              );
+            }
           }
         }
 
@@ -163,15 +257,6 @@ export async function runNonInteractive(
       const initialParts = normalizePartList(initialPartList);
       let currentMessages: Content[] = [{ role: 'user', parts: initialParts }];
 
-      if (adapter) {
-        const systemMessage = await buildSystemMessage(
-          config,
-          sessionId,
-          permissionMode,
-        );
-        adapter.emitMessage(systemMessage);
-      }
-
       let isFirstTurn = true;
       while (true) {
         turnCount++;

packages/cli/src/nonInteractiveCliCommands.test.ts

@@ -0,0 +1,242 @@
+/**
+ * @license
+ * Copyright 2025 Qwen Team
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { handleSlashCommand } from './nonInteractiveCliCommands.js';
+import type { Config } from '@qwen-code/qwen-code-core';
+import type { LoadedSettings } from './config/settings.js';
+import { CommandKind } from './ui/commands/types.js';
+
+// Mock the CommandService
+const mockGetCommands = vi.hoisted(() => vi.fn());
+const mockCommandServiceCreate = vi.hoisted(() => vi.fn());
+vi.mock('./services/CommandService.js', () => ({
+  CommandService: {
+    create: mockCommandServiceCreate,
+  },
+}));
+
+describe('handleSlashCommand', () => {
+  let mockConfig: Config;
+  let mockSettings: LoadedSettings;
+  let abortController: AbortController;
+
+  beforeEach(() => {
+    mockCommandServiceCreate.mockResolvedValue({
+      getCommands: mockGetCommands,
+    });
+
+    mockConfig = {
+      getExperimentalZedIntegration: vi.fn().mockReturnValue(false),
+      isInteractive: vi.fn().mockReturnValue(false),
+      getSessionId: vi.fn().mockReturnValue('test-session'),
+      getFolderTrustFeature: vi.fn().mockReturnValue(false),
+      getFolderTrust: vi.fn().mockReturnValue(false),
+      getProjectRoot: vi.fn().mockReturnValue('/test/project'),
+      storage: {},
+    } as unknown as Config;
+
+    mockSettings = {
+      system: { path: '', settings: {} },
+      systemDefaults: { path: '', settings: {} },
+      user: { path: '', settings: {} },
+      workspace: { path: '', settings: {} },
+    } as LoadedSettings;
+
+    abortController = new AbortController();
+  });
+
+  it('should return no_command for non-slash input', async () => {
+    const result = await handleSlashCommand(
+      'regular text',
+      abortController,
+      mockConfig,
+      mockSettings,
+    );
+
+    expect(result.type).toBe('no_command');
+  });
+
+  it('should return no_command for unknown slash commands', async () => {
+    mockGetCommands.mockReturnValue([]);
+
+    const result = await handleSlashCommand(
+      '/unknowncommand',
+      abortController,
+      mockConfig,
+      mockSettings,
+    );
+
+    expect(result.type).toBe('no_command');
+  });
+
+  it('should return unsupported for known built-in commands not in allowed list', async () => {
+    const mockHelpCommand = {
+      name: 'help',
+      description: 'Show help',
+      kind: CommandKind.BUILT_IN,
+      action: vi.fn(),
+    };
+    mockGetCommands.mockReturnValue([mockHelpCommand]);
+
+    const result = await handleSlashCommand(
+      '/help',
+      abortController,
+      mockConfig,
+      mockSettings,
+      [], // Empty allowed list
+    );
+
+    expect(result.type).toBe('unsupported');
+    if (result.type === 'unsupported') {
+      expect(result.reason).toContain('/help');
+      expect(result.reason).toContain('not supported');
+    }
+  });
+
+  it('should return unsupported for /help when using default allowed list', async () => {
+    const mockHelpCommand = {
+      name: 'help',
+      description: 'Show help',
+      kind: CommandKind.BUILT_IN,
+      action: vi.fn(),
+    };
+    mockGetCommands.mockReturnValue([mockHelpCommand]);
+
+    const result = await handleSlashCommand(
+      '/help',
+      abortController,
+      mockConfig,
+      mockSettings,
+      // Default allowed list: ['init', 'summary', 'compress']
+    );
+
+    expect(result.type).toBe('unsupported');
+    if (result.type === 'unsupported') {
+      expect(result.reason).toBe(
+        'The command "/help" is not supported in non-interactive mode.',
+      );
+    }
+  });
+
+  it('should execute allowed built-in commands', async () => {
+    const mockInitCommand = {
+      name: 'init',
+      description: 'Initialize project',
+      kind: CommandKind.BUILT_IN,
+      action: vi.fn().mockResolvedValue({
+        type: 'message',
+        messageType: 'info',
+        content: 'Project initialized',
+      }),
+    };
+    mockGetCommands.mockReturnValue([mockInitCommand]);
+
+    const result = await handleSlashCommand(
+      '/init',
+      abortController,
+      mockConfig,
+      mockSettings,
+      ['init'], // init is in the allowed list
+    );
+
+    expect(result.type).toBe('message');
+    if (result.type === 'message') {
+      expect(result.content).toBe('Project initialized');
+    }
+  });
+
+  it('should execute file commands regardless of allowed list', async () => {
+    const mockFileCommand = {
+      name: 'custom',
+      description: 'Custom file command',
+      kind: CommandKind.FILE,
+      action: vi.fn().mockResolvedValue({
+        type: 'submit_prompt',
+        content: [{ text: 'Custom prompt' }],
+      }),
+    };
+    mockGetCommands.mockReturnValue([mockFileCommand]);
+
+    const result = await handleSlashCommand(
+      '/custom',
+      abortController,
+      mockConfig,
+      mockSettings,
+      [], // Empty allowed list, but FILE commands should still work
+    );
+
+    expect(result.type).toBe('submit_prompt');
+    if (result.type === 'submit_prompt') {
+      expect(result.content).toEqual([{ text: 'Custom prompt' }]);
+    }
+  });
+
+  it('should return unsupported for other built-in commands like /quit', async () => {
+    const mockQuitCommand = {
+      name: 'quit',
+      description: 'Quit application',
+      kind: CommandKind.BUILT_IN,
+      action: vi.fn(),
+    };
+    mockGetCommands.mockReturnValue([mockQuitCommand]);
+
+    const result = await handleSlashCommand(
+      '/quit',
+      abortController,
+      mockConfig,
+      mockSettings,
+    );
+
+    expect(result.type).toBe('unsupported');
+    if (result.type === 'unsupported') {
+      expect(result.reason).toContain('/quit');
+      expect(result.reason).toContain('not supported');
+    }
+  });
+
+  it('should handle command with no action', async () => {
+    const mockCommand = {
+      name: 'noaction',
+      description: 'Command without action',
+      kind: CommandKind.FILE,
+      // No action property
+    };
+    mockGetCommands.mockReturnValue([mockCommand]);
+
+    const result = await handleSlashCommand(
+      '/noaction',
+      abortController,
+      mockConfig,
+      mockSettings,
+    );
+
+    expect(result.type).toBe('no_command');
+  });
+
+  it('should return message when command returns void', async () => {
+    const mockCommand = {
+      name: 'voidcmd',
+      description: 'Command that returns void',
+      kind: CommandKind.FILE,
+      action: vi.fn().mockResolvedValue(undefined),
+    };
+    mockGetCommands.mockReturnValue([mockCommand]);
+
+    const result = await handleSlashCommand(
+      '/voidcmd',
+      abortController,
+      mockConfig,
+      mockSettings,
+    );
+
+    expect(result.type).toBe('message');
+    if (result.type === 'message') {
+      expect(result.content).toBe('Command executed successfully.');
+      expect(result.messageType).toBe('info');
+    }
+  });
+});

packages/cli/src/nonInteractiveCliCommands.ts

@@ -7,7 +7,6 @@
 import type { PartListUnion } from '@google/genai';
 import { parseSlashCommand } from './utils/commands.js';
 import {
-  FatalInputError,
   Logger,
   uiTelemetryService,
   type Config,
@@ -19,10 +18,164 @@ import {
   CommandKind,
   type CommandContext,
   type SlashCommand,
+  type SlashCommandActionReturn,
 } from './ui/commands/types.js';
 import { createNonInteractiveUI } from './ui/noninteractive/nonInteractiveUi.js';
 import type { LoadedSettings } from './config/settings.js';
 import type { SessionStatsState } from './ui/contexts/SessionContext.js';
+import { t } from './i18n/index.js';
+
+/**
+ * Built-in commands that are allowed in non-interactive modes (CLI and ACP).
+ * Only safe, read-only commands that don't require interactive UI.
+ *
+ * These commands are:
+ * - init: Initialize project configuration
+ * - summary: Generate session summary
+ * - compress: Compress conversation history
+ */
+export const ALLOWED_BUILTIN_COMMANDS_NON_INTERACTIVE = [
+  'init',
+  'summary',
+  'compress',
+] as const;
+
+/**
+ * Result of handling a slash command in non-interactive mode.
+ *
+ * Supported types:
+ * - 'submit_prompt': Submits content to the model (supports all modes)
+ * - 'message': Returns a single message (supports non-interactive JSON/text only)
+ * - 'stream_messages': Streams multiple messages (supports ACP only)
+ * - 'unsupported': Command cannot be executed in this mode
+ * - 'no_command': No command was found or executed
+ */
+export type NonInteractiveSlashCommandResult =
+  | {
+      type: 'submit_prompt';
+      content: PartListUnion;
+    }
+  | {
+      type: 'message';
+      messageType: 'info' | 'error';
+      content: string;
+    }
+  | {
+      type: 'stream_messages';
+      messages: AsyncGenerator<
+        { messageType: 'info' | 'error'; content: string },
+        void,
+        unknown
+      >;
+    }
+  | {
+      type: 'unsupported';
+      reason: string;
+      originalType: string;
+    }
+  | {
+      type: 'no_command';
+    };
+
+/**
+ * Converts a SlashCommandActionReturn to a NonInteractiveSlashCommandResult.
+ *
+ * Only the following result types are supported in non-interactive mode:
+ * - submit_prompt: Submits content to the model (all modes)
+ * - message: Returns a single message (non-interactive JSON/text only)
+ * - stream_messages: Streams multiple messages (ACP only)
+ *
+ * All other result types are converted to 'unsupported'.
+ *
+ * @param result The result from executing a slash command action
+ * @returns A NonInteractiveSlashCommandResult describing the outcome
+ */
+function handleCommandResult(
+  result: SlashCommandActionReturn,
+): NonInteractiveSlashCommandResult {
+  switch (result.type) {
+    case 'submit_prompt':
+      return {
+        type: 'submit_prompt',
+        content: result.content,
+      };
+
+    case 'message':
+      return {
+        type: 'message',
+        messageType: result.messageType,
+        content: result.content,
+      };
+
+    case 'stream_messages':
+      return {
+        type: 'stream_messages',
+        messages: result.messages,
+      };
+
+    /**
+     * Currently return types below are never generated due to the
+     * whitelist of allowed slash commands in ACP and non-interactive mode.
+     * We'll try to add more supported return types in the future.
+     */
+    case 'tool':
+      return {
+        type: 'unsupported',
+        reason:
+          'Tool execution from slash commands is not supported in non-interactive mode.',
+        originalType: 'tool',
+      };
+
+    case 'quit':
+      return {
+        type: 'unsupported',
+        reason:
+          'Quit command is not supported in non-interactive mode. The process will exit naturally after completion.',
+        originalType: 'quit',
+      };
+
+    case 'dialog':
+      return {
+        type: 'unsupported',
+        reason: `Dialog '${result.dialog}' cannot be opened in non-interactive mode.`,
+        originalType: 'dialog',
+      };
+
+    case 'load_history':
+      return {
+        type: 'unsupported',
+        reason:
+          'Loading history is not supported in non-interactive mode. Each invocation starts with a fresh context.',
+        originalType: 'load_history',
+      };
+
+    case 'confirm_shell_commands':
+      return {
+        type: 'unsupported',
+        reason:
+          'Shell command confirmation is not supported in non-interactive mode. Use YOLO mode or pre-approve commands.',
+        originalType: 'confirm_shell_commands',
+      };
+
+    case 'confirm_action':
+      return {
+        type: 'unsupported',
+        reason:
+          'Action confirmation is not supported in non-interactive mode. Commands requiring confirmation cannot be executed.',
+        originalType: 'confirm_action',
+      };
+
+    default: {
+      // Exhaustiveness check
+      const _exhaustive: never = result;
+      return {
+        type: 'unsupported',
+        reason: `Unknown command result type: ${(_exhaustive as SlashCommandActionReturn).type}`,
+        originalType: 'unknown',
+      };
+    }
+  }
+}
 
 /**
  * Filters commands based on the allowed built-in command names.
@@ -62,122 +215,146 @@ function filterCommandsForNonInteractive(
  * @param config The configuration object
  * @param settings The loaded settings
  * @param allowedBuiltinCommandNames Optional array of built-in command names that are
- *   allowed. If not provided or empty, only file commands are available.
- * @returns A Promise that resolves to `PartListUnion` if a valid command is
- *   found and results in a prompt, or `undefined` otherwise.
- * @throws {FatalInputError} if the command result is not supported in
- *   non-interactive mode.
+ *   allowed. Defaults to ALLOWED_BUILTIN_COMMANDS_NON_INTERACTIVE (init, summary, compress).
+ *   Pass an empty array to only allow file commands.
+ * @returns A Promise that resolves to a `NonInteractiveSlashCommandResult` describing
+ *   the outcome of the command execution.
  */
 export const handleSlashCommand = async (
   rawQuery: string,
   abortController: AbortController,
   config: Config,
   settings: LoadedSettings,
-  allowedBuiltinCommandNames?: string[],
-): Promise<PartListUnion | undefined> => {
+  allowedBuiltinCommandNames: string[] = [
+    ...ALLOWED_BUILTIN_COMMANDS_NON_INTERACTIVE,
+  ],
+): Promise<NonInteractiveSlashCommandResult> => {
   const trimmed = rawQuery.trim();
   if (!trimmed.startsWith('/')) {
-    return;
+    return { type: 'no_command' };
   }
 
+  const isAcpMode = config.getExperimentalZedIntegration();
+  const isInteractive = config.isInteractive();
+
+  const executionMode = isAcpMode
+    ? 'acp'
+    : isInteractive
+      ? 'interactive'
+      : 'non_interactive';
+
   const allowedBuiltinSet = new Set(allowedBuiltinCommandNames ?? []);
 
-  // Only load BuiltinCommandLoader if there are allowed built-in commands
-  const loaders =
-    allowedBuiltinSet.size > 0
-      ? [new BuiltinCommandLoader(config), new FileCommandLoader(config)]
-      : [new FileCommandLoader(config)];
+  // Load all commands to check if the command exists but is not allowed
+  const allLoaders = [
+    new BuiltinCommandLoader(config),
+    new FileCommandLoader(config),
+  ];
 
   const commandService = await CommandService.create(
-    loaders,
+    allLoaders,
     abortController.signal,
   );
-  const commands = commandService.getCommands();
+  const allCommands = commandService.getCommands();
   const filteredCommands = filterCommandsForNonInteractive(
-    commands,
+    allCommands,
     allowedBuiltinSet,
   );
 
+  // First, try to parse with filtered commands
   const { commandToExecute, args } = parseSlashCommand(
     rawQuery,
     filteredCommands,
   );
 
-  if (commandToExecute) {
-    if (commandToExecute.action) {
-      // Not used by custom commands but may be in the future.
-      const sessionStats: SessionStatsState = {
-        sessionId: config?.getSessionId(),
-        sessionStartTime: new Date(),
-        metrics: uiTelemetryService.getMetrics(),
-        lastPromptTokenCount: 0,
-        promptCount: 1,
+  if (!commandToExecute) {
+    // Check if this is a known command that's just not allowed
+    const { commandToExecute: knownCommand } = parseSlashCommand(
+      rawQuery,
+      allCommands,
+    );
+
+    if (knownCommand) {
+      // Command exists but is not allowed in non-interactive mode
+      return {
+        type: 'unsupported',
+        reason: t(
+          'The command "/{{command}}" is not supported in non-interactive mode.',
+          { command: knownCommand.name },
+        ),
+        originalType: 'filtered_command',
       };
-
-      const logger = new Logger(config?.getSessionId() || '', config?.storage);
-
-      const context: CommandContext = {
-        services: {
-          config,
-          settings,
-          git: undefined,
-          logger,
-        },
-        ui: createNonInteractiveUI(),
-        session: {
-          stats: sessionStats,
-          sessionShellAllowlist: new Set(),
-        },
-        invocation: {
-          raw: trimmed,
-          name: commandToExecute.name,
-          args,
-        },
-      };
-
-      const result = await commandToExecute.action(context, args);
-
-      if (result) {
-        switch (result.type) {
-          case 'submit_prompt':
-            return result.content;
-          case 'confirm_shell_commands':
-            // This result indicates a command attempted to confirm shell commands.
-            // However note that currently, ShellTool is excluded in non-interactive
-            // mode unless 'YOLO mode' is active, so confirmation actually won't
-            // occur because of YOLO mode.
-            // This ensures that if a command *does* request confirmation (e.g.
-            // in the future with more granular permissions), it's handled appropriately.
-            throw new FatalInputError(
-              'Exiting due to a confirmation prompt requested by the command.',
-            );
-          default:
-            throw new FatalInputError(
-              'Exiting due to command result that is not supported in non-interactive mode.',
-            );
-        }
-      }
     }
+
+    return { type: 'no_command' };
   }
 
-  return;
+  if (!commandToExecute.action) {
+    return { type: 'no_command' };
+  }
+
+  // Not used by custom commands but may be in the future.
+  const sessionStats: SessionStatsState = {
+    sessionId: config?.getSessionId(),
+    sessionStartTime: new Date(),
+    metrics: uiTelemetryService.getMetrics(),
+    lastPromptTokenCount: 0,
+    promptCount: 1,
+  };
+
+  const logger = new Logger(config?.getSessionId() || '', config?.storage);
+
+  const context: CommandContext = {
+    executionMode,
+    services: {
+      config,
+      settings,
+      git: undefined,
+      logger,
+    },
+    ui: createNonInteractiveUI(),
+    session: {
+      stats: sessionStats,
+      sessionShellAllowlist: new Set(),
+    },
+    invocation: {
+      raw: trimmed,
+      name: commandToExecute.name,
+      args,
+    },
+  };
+
+  const result = await commandToExecute.action(context, args);
+
+  if (!result) {
+    // Command executed but returned no result (e.g., void return)
+    return {
+      type: 'message',
+      messageType: 'info',
+      content: 'Command executed successfully.',
+    };
+  }
+
+  // Handle different result types
+  return handleCommandResult(result);
 };
 
 /**
  * Retrieves all available slash commands for the current configuration.
  *
  * @param config The configuration object
- * @param settings The loaded settings
  * @param abortSignal Signal to cancel the loading process
  * @param allowedBuiltinCommandNames Optional array of built-in command names that are
- *   allowed. If not provided or empty, only file commands are available.
+ *   allowed. Defaults to ALLOWED_BUILTIN_COMMANDS_NON_INTERACTIVE (init, summary, compress).
+ *   Pass an empty array to only include file commands.
  * @returns A Promise that resolves to an array of SlashCommand objects
  */
 export const getAvailableCommands = async (
   config: Config,
-  settings: LoadedSettings,
   abortSignal: AbortSignal,
-  allowedBuiltinCommandNames?: string[],
+  allowedBuiltinCommandNames: string[] = [
+    ...ALLOWED_BUILTIN_COMMANDS_NON_INTERACTIVE,
+  ],
 ): Promise<SlashCommand[]> => {
   try {
     const allowedBuiltinSet = new Set(allowedBuiltinCommandNames ?? []);

packages/cli/src/ui/commands/compressCommand.ts

@@ -19,7 +19,9 @@ export const compressCommand: SlashCommand = {
   kind: CommandKind.BUILT_IN,
   action: async (context) => {
     const { ui } = context;
-    if (ui.pendingItem) {
+    const executionMode = context.executionMode ?? 'interactive';
+
+    if (executionMode === 'interactive' && ui.pendingItem) {
       ui.addItem(
         {
           type: MessageType.ERROR,
@@ -40,13 +42,80 @@ export const compressCommand: SlashCommand = {
       },
     };
 
-    try {
-      ui.setPendingItem(pendingMessage);
+    const config = context.services.config;
+    const geminiClient = config?.getGeminiClient();
+    if (!config || !geminiClient) {
+      return {
+        type: 'message',
+        messageType: 'error',
+        content: t('Config not loaded.'),
+      };
+    }
+
+    const doCompress = async () => {
       const promptId = `compress-${Date.now()}`;
-      const compressed = await context.services.config
-        ?.getGeminiClient()
-        ?.tryCompressChat(promptId, true);
-      if (compressed) {
+      return await geminiClient.tryCompressChat(promptId, true);
+    };
+
+    if (executionMode === 'acp') {
+      const messages = async function* () {
+        try {
+          yield {
+            messageType: 'info' as const,
+            content: 'Compressing context...',
+          };
+          const compressed = await doCompress();
+          if (!compressed) {
+            yield {
+              messageType: 'error' as const,
+              content: t('Failed to compress chat history.'),
+            };
+            return;
+          }
+          yield {
+            messageType: 'info' as const,
+            content: `Context compressed (${compressed.originalTokenCount} -> ${compressed.newTokenCount}).`,
+          };
+        } catch (e) {
+          yield {
+            messageType: 'error' as const,
+            content: t('Failed to compress chat history: {{error}}', {
+              error: e instanceof Error ? e.message : String(e),
+            }),
+          };
+        }
+      };
+
+      return { type: 'stream_messages', messages: messages() };
+    }
+
+    try {
+      if (executionMode === 'interactive') {
+        ui.setPendingItem(pendingMessage);
+      }
+
+      const compressed = await doCompress();
+
+      if (!compressed) {
+        if (executionMode === 'interactive') {
+          ui.addItem(
+            {
+              type: MessageType.ERROR,
+              text: t('Failed to compress chat history.'),
+            },
+            Date.now(),
+          );
+          return;
+        }
+
+        return {
+          type: 'message',
+          messageType: 'error',
+          content: t('Failed to compress chat history.'),
+        };
+      }
+
+      if (executionMode === 'interactive') {
         ui.addItem(
           {
             type: MessageType.COMPRESSION,
@@ -59,27 +128,39 @@ export const compressCommand: SlashCommand = {
           } as HistoryItemCompression,
           Date.now(),
         );
-      } else {
+        return;
+      }
+
+      return {
+        type: 'message',
+        messageType: 'info',
+        content: `Context compressed (${compressed.originalTokenCount} -> ${compressed.newTokenCount}).`,
+      };
+    } catch (e) {
+      if (executionMode === 'interactive') {
         ui.addItem(
           {
             type: MessageType.ERROR,
-            text: t('Failed to compress chat history.'),
+            text: t('Failed to compress chat history: {{error}}', {
+              error: e instanceof Error ? e.message : String(e),
+            }),
           },
           Date.now(),
         );
+        return;
       }
-    } catch (e) {
-      ui.addItem(
-        {
-          type: MessageType.ERROR,
-          text: t('Failed to compress chat history: {{error}}', {
-            error: e instanceof Error ? e.message : String(e),
-          }),
-        },
-        Date.now(),
-      );
+
+      return {
+        type: 'message',
+        messageType: 'error',
+        content: t('Failed to compress chat history: {{error}}', {
+          error: e instanceof Error ? e.message : String(e),
+        }),
+      };
     } finally {
-      ui.setPendingItem(null);
+      if (executionMode === 'interactive') {
+        ui.setPendingItem(null);
+      }
     }
   },
 };

packages/cli/src/ui/commands/summaryCommand.ts

@@ -26,6 +26,8 @@ export const summaryCommand: SlashCommand = {
   action: async (context): Promise<SlashCommandActionReturn> => {
     const { config } = context.services;
     const { ui } = context;
+    const executionMode = context.executionMode ?? 'interactive';
+
     if (!config) {
       return {
         type: 'message',
@@ -43,8 +45,8 @@ export const summaryCommand: SlashCommand = {
       };
     }
 
-    // Check if already generating summary
-    if (ui.pendingItem) {
+    // Check if already generating summary (interactive UI only)
+    if (executionMode === 'interactive' && ui.pendingItem) {
       ui.addItem(
         {
           type: 'error' as const,
@@ -63,29 +65,22 @@ export const summaryCommand: SlashCommand = {
       };
     }
 
-    try {
-      // Get the current chat history
+    const getChatHistory = () => {
       const chat = geminiClient.getChat();
-      const history = chat.getHistory();
+      return chat.getHistory();
+    };
 
+    const validateChatHistory = (
+      history: ReturnType<typeof getChatHistory>,
+    ) => {
       if (history.length <= 2) {
-        return {
-          type: 'message',
-          messageType: 'info',
-          content: t('No conversation found to summarize.'),
-        };
+        throw new Error(t('No conversation found to summarize.'));
       }
+    };
 
-      // Show loading state
-      const pendingMessage: HistoryItemSummary = {
-        type: 'summary',
-        summary: {
-          isPending: true,
-          stage: 'generating',
-        },
-      };
-      ui.setPendingItem(pendingMessage);
-
+    const generateSummaryMarkdown = async (
+      history: ReturnType<typeof getChatHistory>,
+    ): Promise<string> => {
       // Build the conversation context for summary generation
       const conversationContext = history.map((message) => ({
         role: message.role,
@@ -121,19 +116,21 @@ export const summaryCommand: SlashCommand = {
 
       if (!markdownSummary) {
         throw new Error(
-          'Failed to generate summary - no text content received from LLM response',
+          t(
+            'Failed to generate summary - no text content received from LLM response',
+          ),
         );
       }
 
-      // Update loading message to show saving progress
-      ui.setPendingItem({
-        type: 'summary',
-        summary: {
-          isPending: true,
-          stage: 'saving',
-        },
-      });
+      return markdownSummary;
+    };
 
+    const saveSummaryToDisk = async (
+      markdownSummary: string,
+    ): Promise<{
+      filePathForDisplay: string;
+      fullPath: string;
+    }> => {
       // Ensure .qwen directory exists
       const projectRoot = config.getProjectRoot();
       const qwenDir = path.join(projectRoot, '.qwen');
@@ -155,45 +152,163 @@ export const summaryCommand: SlashCommand = {
 
       await fsPromises.writeFile(summaryPath, summaryContent, 'utf8');
 
-      // Clear pending item and show success message
+      return {
+        filePathForDisplay: '.qwen/PROJECT_SUMMARY.md',
+        fullPath: summaryPath,
+      };
+    };
+
+    const emitInteractivePending = (stage: 'generating' | 'saving') => {
+      if (executionMode !== 'interactive') {
+        return;
+      }
+      const pendingMessage: HistoryItemSummary = {
+        type: 'summary',
+        summary: {
+          isPending: true,
+          stage,
+        },
+      };
+      ui.setPendingItem(pendingMessage);
+    };
+
+    const completeInteractive = (filePathForDisplay: string) => {
+      if (executionMode !== 'interactive') {
+        return;
+      }
       ui.setPendingItem(null);
       const completedSummaryItem: HistoryItemSummary = {
         type: 'summary',
         summary: {
           isPending: false,
           stage: 'completed',
-          filePath: '.qwen/PROJECT_SUMMARY.md',
+          filePath: filePathForDisplay,
         },
       };
       ui.addItem(completedSummaryItem, Date.now());
+    };
 
-      return {
-        type: 'message',
-        messageType: 'info',
-        content: '', // Empty content since we show the message in UI component
-      };
-    } catch (error) {
-      // Clear pending item on error
+    const formatErrorMessage = (error: unknown): string =>
+      t('Failed to generate project context summary: {{error}}', {
+        error: error instanceof Error ? error.message : String(error),
+      });
+
+    const failInteractive = (error: unknown) => {
+      if (executionMode !== 'interactive') {
+        return;
+      }
       ui.setPendingItem(null);
       ui.addItem(
         {
           type: 'error' as const,
-          text: `❌ ${t(
-            'Failed to generate project context summary: {{error}}',
-            {
-              error: error instanceof Error ? error.message : String(error),
-            },
-          )}`,
+          text: `❌ ${formatErrorMessage(error)}`,
         },
         Date.now(),
       );
+    };
+
+    const formatSuccessMessage = (filePathForDisplay: string): string =>
+      t('Saved project summary to {{filePathForDisplay}}.', {
+        filePathForDisplay,
+      });
+
+    const returnNoConversationMessage = (): SlashCommandActionReturn => {
+      const msg = t('No conversation found to summarize.');
+      if (executionMode === 'acp') {
+        const messages = async function* () {
+          yield {
+            messageType: 'info' as const,
+            content: msg,
+          };
+        };
+        return {
+          type: 'stream_messages',
+          messages: messages(),
+        };
+      }
+      return {
+        type: 'message',
+        messageType: 'info',
+        content: msg,
+      };
+    };
+
+    const executeSummaryGeneration = async (
+      history: ReturnType<typeof getChatHistory>,
+    ): Promise<{
+      markdownSummary: string;
+      filePathForDisplay: string;
+    }> => {
+      emitInteractivePending('generating');
+      const markdownSummary = await generateSummaryMarkdown(history);
+      emitInteractivePending('saving');
+      const { filePathForDisplay } = await saveSummaryToDisk(markdownSummary);
+      completeInteractive(filePathForDisplay);
+      return { markdownSummary, filePathForDisplay };
+    };
+
+    // Validate chat history once at the beginning
+    const history = getChatHistory();
+    try {
+      validateChatHistory(history);
+    } catch (_error) {
+      return returnNoConversationMessage();
+    }
+
+    if (executionMode === 'acp') {
+      const messages = async function* () {
+        try {
+          yield {
+            messageType: 'info' as const,
+            content: t('Generating project summary...'),
+          };
+
+          const { filePathForDisplay } =
+            await executeSummaryGeneration(history);
+
+          yield {
+            messageType: 'info' as const,
+            content: formatSuccessMessage(filePathForDisplay),
+          };
+        } catch (error) {
+          failInteractive(error);
+          yield {
+            messageType: 'error' as const,
+            content: formatErrorMessage(error),
+          };
+        }
+      };
+
+      return {
+        type: 'stream_messages',
+        messages: messages(),
+      };
+    }
+
+    try {
+      const { filePathForDisplay } = await executeSummaryGeneration(history);
+
+      if (executionMode === 'non_interactive') {
+        return {
+          type: 'message',
+          messageType: 'info',
+          content: formatSuccessMessage(filePathForDisplay),
+        };
+      }
+
+      // Interactive mode: UI components already display progress and completion.
+      return {
+        type: 'message',
+        messageType: 'info',
+        content: '',
+      };
+    } catch (error) {
+      failInteractive(error);
 
       return {
         type: 'message',
         messageType: 'error',
-        content: t('Failed to generate project context summary: {{error}}', {
-          error: error instanceof Error ? error.message : String(error),
-        }),
+        content: formatErrorMessage(error),
       };
     }
   },

packages/cli/src/ui/commands/types.ts

@@ -22,6 +22,14 @@ import type {
 
 // Grouped dependencies for clarity and easier mocking
 export interface CommandContext {
+  /**
+   * Execution mode for the current invocation.
+   *
+   * - interactive: React/Ink UI mode
+   * - non_interactive: non-interactive CLI mode (text/json)
+   * - acp: ACP/Zed integration mode
+   */
+  executionMode?: 'interactive' | 'non_interactive' | 'acp';
   // Invocation properties for when commands are called.
   invocation?: {
     /** The raw, untrimmed input string from the user. */
@@ -108,6 +116,19 @@ export interface MessageActionReturn {
   content: string;
 }
 
+/**
+ * The return type for a command action that streams multiple messages.
+ * Used for long-running operations that need to send progress updates.
+ */
+export interface StreamMessagesActionReturn {
+  type: 'stream_messages';
+  messages: AsyncGenerator<
+    { messageType: 'info' | 'error'; content: string },
+    void,
+    unknown
+  >;
+}
+
 /**
  * The return type for a command action that needs to open a dialog.
  */
@@ -174,6 +195,7 @@ export interface ConfirmActionReturn {
 export type SlashCommandActionReturn =
   | ToolActionReturn
   | MessageActionReturn
+  | StreamMessagesActionReturn
   | QuitActionReturn
   | OpenDialogActionReturn
   | LoadHistoryActionReturn

packages/cli/src/ui/hooks/slashCommandProcessor.ts

@@ -520,6 +520,13 @@ export const useSlashCommandProcessor = (
                     true,
                   );
                 }
+                case 'stream_messages': {
+                  // stream_messages is only used in ACP/Zed integration mode
+                  // and should not be returned in interactive UI mode
+                  throw new Error(
+                    'stream_messages result type is not supported in interactive mode',
+                  );
+                }
                 default: {
                   const unhandled: never = result;
                   throw new Error(

packages/cli/src/utils/nonInteractiveHelpers.test.ts

@@ -35,22 +35,33 @@ import {
 } from './nonInteractiveHelpers.js';
 
 // Mock dependencies
-vi.mock('../services/CommandService.js', () => ({
-  CommandService: {
-    create: vi.fn().mockResolvedValue({
-      getCommands: vi
-        .fn()
-        .mockReturnValue([
-          { name: 'help' },
-          { name: 'commit' },
-          { name: 'memory' },
-        ]),
-    }),
-  },
-}));
+vi.mock('../nonInteractiveCliCommands.js', () => ({
+  getAvailableCommands: vi
+    .fn()
+    .mockImplementation(
+      async (
+        _config: unknown,
+        _signal: AbortSignal,
+        allowedBuiltinCommandNames?: string[],
+      ) => {
+        const allowedSet = new Set(allowedBuiltinCommandNames ?? []);
+        const allCommands = [
+          { name: 'help', kind: 'built-in' },
+          { name: 'commit', kind: 'file' },
+          { name: 'memory', kind: 'built-in' },
+          { name: 'init', kind: 'built-in' },
+          { name: 'summary', kind: 'built-in' },
+          { name: 'compress', kind: 'built-in' },
+        ];
 
-vi.mock('../services/BuiltinCommandLoader.js', () => ({
-  BuiltinCommandLoader: vi.fn().mockImplementation(() => ({})),
+        // Filter commands: always include file commands, only include allowed built-in commands
+        return allCommands.filter(
+          (cmd) =>
+            cmd.kind === 'file' ||
+            (cmd.kind === 'built-in' && allowedSet.has(cmd.name)),
+        );
+      },
+    ),
 }));
 
 vi.mock('../ui/utils/computeStats.js', () => ({
@@ -511,10 +522,12 @@ describe('buildSystemMessage', () => {
   });
 
   it('should build system message with all fields', async () => {
+    const allowedBuiltinCommands = ['init', 'summary', 'compress'];
     const result = await buildSystemMessage(
       mockConfig,
       'test-session-id',
       'auto' as PermissionMode,
+      allowedBuiltinCommands,
     );
 
     expect(result).toEqual({
@@ -530,7 +543,7 @@ describe('buildSystemMessage', () => {
       ],
       model: 'test-model',
       permission_mode: 'auto',
-      slash_commands: ['commit', 'help', 'memory'],
+      slash_commands: ['commit', 'compress', 'init', 'summary'],
       qwen_code_version: '1.0.0',
       agents: [],
     });
@@ -546,6 +559,7 @@ describe('buildSystemMessage', () => {
       config,
       'test-session-id',
       'auto' as PermissionMode,
+      ['init', 'summary'],
     );
 
     expect(result.tools).toEqual([]);
@@ -561,6 +575,7 @@ describe('buildSystemMessage', () => {
       config,
       'test-session-id',
       'auto' as PermissionMode,
+      ['init', 'summary'],
     );
 
     expect(result.mcp_servers).toEqual([]);
@@ -576,10 +591,37 @@ describe('buildSystemMessage', () => {
       config,
       'test-session-id',
       'auto' as PermissionMode,
+      ['init', 'summary'],
     );
 
     expect(result.qwen_code_version).toBe('unknown');
   });
+
+  it('should only include allowed built-in commands and all file commands', async () => {
+    const allowedBuiltinCommands = ['init', 'summary'];
+    const result = await buildSystemMessage(
+      mockConfig,
+      'test-session-id',
+      'auto' as PermissionMode,
+      allowedBuiltinCommands,
+    );
+
+    // Should include: 'commit' (FILE), 'init' (BUILT_IN, allowed), 'summary' (BUILT_IN, allowed)
+    // Should NOT include: 'help', 'memory', 'compress' (BUILT_IN but not in allowed set)
+    expect(result.slash_commands).toEqual(['commit', 'init', 'summary']);
+  });
+
+  it('should include only file commands when no built-in commands are allowed', async () => {
+    const result = await buildSystemMessage(
+      mockConfig,
+      'test-session-id',
+      'auto' as PermissionMode,
+      [], // Empty array - no built-in commands allowed
+    );
+
+    // Should only include 'commit' (FILE command)
+    expect(result.slash_commands).toEqual(['commit']);
+  });
 });
 
 describe('createTaskToolProgressHandler', () => {

packages/cli/src/utils/nonInteractiveHelpers.ts

@@ -25,10 +25,9 @@ import type {
   PermissionMode,
   CLISystemMessage,
 } from '../nonInteractive/types.js';
-import { CommandService } from '../services/CommandService.js';
-import { BuiltinCommandLoader } from '../services/BuiltinCommandLoader.js';
 import type { JsonOutputAdapterInterface } from '../nonInteractive/io/BaseJsonOutputAdapter.js';
 import { computeSessionStats } from '../ui/utils/computeStats.js';
+import { getAvailableCommands } from '../nonInteractiveCliCommands.js';
 
 /**
  * Normalizes various part list formats into a consistent Part[] array.
@@ -187,24 +186,27 @@ export function computeUsageFromMetrics(metrics: SessionMetrics): Usage {
 }
 
 /**
- * Load slash command names using CommandService
+ * Load slash command names using getAvailableCommands
  *
  * @param config - Config instance
+ * @param allowedBuiltinCommandNames - Optional array of allowed built-in command names.
+ *   If not provided, uses the default from getAvailableCommands.
  * @returns Promise resolving to array of slash command names
  */
-async function loadSlashCommandNames(config: Config): Promise<string[]> {
+async function loadSlashCommandNames(
+  config: Config,
+  allowedBuiltinCommandNames?: string[],
+): Promise<string[]> {
   const controller = new AbortController();
   try {
-    const service = await CommandService.create(
-      [new BuiltinCommandLoader(config)],
+    const commands = await getAvailableCommands(
+      config,
       controller.signal,
+      allowedBuiltinCommandNames,
     );
-    const names = new Set<string>();
-    const commands = service.getCommands();
-    for (const command of commands) {
-      names.add(command.name);
-    }
-    return Array.from(names).sort();
+
+    // Extract command names and sort
+    return commands.map((cmd) => cmd.name).sort();
   } catch (error) {
     if (config.getDebugMode()) {
       console.error(
@@ -233,12 +235,15 @@ async function loadSlashCommandNames(config: Config): Promise<string[]> {
  * @param config - Config instance
  * @param sessionId - Session identifier
  * @param permissionMode - Current permission/approval mode
+ * @param allowedBuiltinCommandNames - Optional array of allowed built-in command names.
+ *   If not provided, defaults to empty array (only file commands will be included).
  * @returns Promise resolving to CLISystemMessage
  */
 export async function buildSystemMessage(
   config: Config,
   sessionId: string,
   permissionMode: PermissionMode,
+  allowedBuiltinCommandNames?: string[],
 ): Promise<CLISystemMessage> {
   const toolRegistry = config.getToolRegistry();
   const tools = toolRegistry ? toolRegistry.getAllToolNames() : [];
@@ -251,8 +256,11 @@ export async function buildSystemMessage(
       }))
     : [];
 
-  // Load slash commands
-  const slashCommands = await loadSlashCommandNames(config);
+  // Load slash commands with filtering based on allowed built-in commands
+  const slashCommands = await loadSlashCommandNames(
+    config,
+    allowedBuiltinCommandNames,
+  );
 
   // Load subagent names from config
   let agentNames: string[] = [];

packages/sdk-typescript/src/query/Query.ts

@@ -272,8 +272,6 @@ export class Query implements AsyncIterable<SDKMessage> {
       // Get only successfully connected SDK servers for CLI
       const sdkMcpServersForCli = this.getSdkMcpServersForCli();
       const mcpServersForCli = this.getMcpServersForCli();
-      logger.debug('SDK MCP servers for CLI:', sdkMcpServersForCli);
-      logger.debug('External MCP servers for CLI:', mcpServersForCli);
 
       await this.sendControlRequest(ControlRequestType.INITIALIZE, {
         hooks: null,
@@ -629,6 +627,11 @@ export class Query implements AsyncIterable<SDKMessage> {
       return Promise.reject(new Error('Query is closed'));
     }
 
+    if (subtype !== ControlRequestType.INITIALIZE) {
+      // Ensure all other control requests get processed after initialization
+      await this.initialized;
+    }
+
     const requestId = randomUUID();
 
     const request: CLIControlRequest = {