refactor(mcp): extract MCP core into shared chatlab-mcp package

Move MCP Server logic (tool registration, resource registration, schema
conversion) from apps/cli/src/mcp.ts to packages/mcp-server so both CLI
and Desktop can share the same MCP implementation.

- New package: chatlab-mcp (packages/mcp-server) with McpDatabaseManager
  interface abstraction
- CLI mcp.ts slimmed to thin entry (~37 lines) calling startMcpServer()
- Desktop helper prototype at apps/desktop/helper/mcp.ts for dev-time
  MCP without GUI
- All 8 MCP tools and 3 resources unchanged

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/cli/package.json

@@ -74,6 +74,7 @@
     "@openchatlab/sync": "workspace:*",
     "@openchatlab/tools": "workspace:*",
     "@types/better-sqlite3": "^7.6.13",
+    "chatlab-mcp": "workspace:*",
     "tsup": "^8.5.0",
     "tsx": "^4.21.0"
   }

apps/cli/src/cli.ts

@@ -269,8 +269,8 @@ program
   .command('mcp')
   .description('Start MCP Server (stdio transport, for Claude Desktop / Cursor / AI agents)')
   .action(async () => {
-    const { startMcpServer } = await import('./mcp')
-    await startMcpServer()
+    const { startCliMcpServer } = await import('./mcp')
+    await startCliMcpServer()
   })
 
 program

apps/cli/src/mcp.ts

@@ -1,14 +1,9 @@
 /**
- * ChatLab MCP Server
+ * CLI MCP Server entry point
  *
- * 通过 stdio 传输协议与 AI 代理（Claude Desktop、Cursor 等）通信。
- * 注册 @openchatlab/tools 中的工具为 MCP tools，
- * 会话列表作为 MCP resources 暴露。
+ * Thin wrapper: initializes Node.js runtime, then delegates to chatlab-mcp.
  */
 
-import { McpServer, ResourceTemplate } from '@modelcontextprotocol/sdk/server/mcp.js'
-import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js'
-import { z } from 'zod'
 import { loadConfig } from '@openchatlab/config'
 import {
   NodePathProvider,
@@ -16,16 +11,10 @@ import {
   hasPendingElectronDataWarning,
   verifyCliDataPath,
 } from '@openchatlab/node-runtime'
-import { getSessionMeta, getSessionOverview, getDatabaseSchema } from '@openchatlab/core'
-import { MCP_TOOL_REGISTRY, CoreDataProvider } from '@openchatlab/tools'
-import type { SessionListContext } from '@openchatlab/tools/src/definitions/sessions'
+import { startMcpServer } from 'chatlab-mcp'
 import { getVersion } from './version'
 
-const MCP_TOOL_PREFIX = 'chatlab_'
-
-let dbManager: DatabaseManager
-
-function initMcpRuntime() {
+function initMcpRuntime(): DatabaseManager {
   const config = loadConfig()
   const userDataDir = config.data.user_data_dir || undefined
   const pathProvider = new NodePathProvider(userDataDir)
@@ -37,180 +26,10 @@ function initMcpRuntime() {
     process.exit(1)
   }
 
-  dbManager = new DatabaseManager(pathProvider)
-  return { config, dbManager }
+  return new DatabaseManager(pathProvider)
 }
 
-/**
- * 将简单的 JSON Schema 属性转为 Zod schema 对象
- */
-function jsonSchemaToZod(
-  properties: Record<string, { type: string; description?: string; default?: unknown; enum?: unknown[] }>,
-  required?: string[]
-): Record<string, z.ZodTypeAny> {
-  const shape: Record<string, z.ZodTypeAny> = {}
-  const requiredSet = new Set(required ?? [])
-
-  for (const [key, prop] of Object.entries(properties)) {
-    let zodType: z.ZodTypeAny
-
-    switch (prop.type) {
-      case 'number':
-        zodType = z.number().describe(prop.description ?? '')
-        break
-      case 'boolean':
-        zodType = z.boolean().describe(prop.description ?? '')
-        break
-      case 'string':
-      default:
-        if (prop.enum) {
-          zodType = z.enum(prop.enum as [string, ...string[]]).describe(prop.description ?? '')
-        } else {
-          zodType = z.string().describe(prop.description ?? '')
-        }
-        break
-    }
-
-    if (!requiredSet.has(key)) {
-      zodType = zodType.optional()
-    }
-
-    shape[key] = zodType
-  }
-
-  return shape
-}
-
-export async function startMcpServer(): Promise<void> {
-  initMcpRuntime()
-
-  const server = new McpServer({
-    name: 'chatlab',
-    version: getVersion(),
-  })
-
-  // --- 注册 Tools ---
-
-  for (const tool of MCP_TOOL_REGISTRY) {
-    const mcpName = `${MCP_TOOL_PREFIX}${tool.name}`
-
-    if (tool.name === 'list_sessions') {
-      const zodShape = jsonSchemaToZod(tool.inputSchema.properties, tool.inputSchema.required)
-
-      server.tool(mcpName, tool.description, zodShape, async (params) => {
-        const context: SessionListContext = {
-          db: null as any,
-          sessionId: '',
-          listSessionIds: () => dbManager.listSessionIds(),
-          openDb: (id) => dbManager.open(id),
-        }
-        const result = await tool.handler(params as Record<string, unknown>, context)
-        return { content: [{ type: 'text' as const, text: result.content }] }
-      })
-      continue
-    }
-
-    const sessionsToolMcpName = `${MCP_TOOL_PREFIX}list_sessions`
-    const zodShape = {
-      session_id: z.string().describe(`Session ID (use ${sessionsToolMcpName} to get available sessions)`),
-      ...jsonSchemaToZod(tool.inputSchema.properties, tool.inputSchema.required),
-    }
-
-    server.tool(mcpName, tool.description, zodShape, async (params) => {
-      const sessionId = params.session_id as string
-      const db = dbManager.open(sessionId)
-      if (!db) {
-        return {
-          content: [{ type: 'text' as const, text: JSON.stringify({ error: `Session ${sessionId} not found` }) }],
-          isError: true,
-        }
-      }
-
-      const toolParams = { ...params } as Record<string, unknown>
-      delete toolParams.session_id
-
-      const result = await tool.handler(toolParams, { db, sessionId, dataProvider: new CoreDataProvider(db) })
-      return { content: [{ type: 'text' as const, text: result.content }] }
-    })
-  }
-
-  // --- 注册 Resources ---
-
-  server.resource('sessions-list', 'chatlab://sessions', { description: '所有已导入的聊天会话列表' }, async () => {
-    const sessionIds = dbManager.listSessionIds()
-    const sessions = sessionIds
-      .map((id) => {
-        const db = dbManager.open(id)
-        if (!db) return null
-        const meta = getSessionMeta(db)
-        if (!meta) return null
-        return { id, name: meta.name, platform: meta.platform, type: meta.type }
-      })
-      .filter(Boolean)
-
-    return {
-      contents: [
-        {
-          uri: 'chatlab://sessions',
-          text: JSON.stringify(sessions, null, 2),
-          mimeType: 'application/json',
-        },
-      ],
-    }
-  })
-
-  server.resource(
-    'session-meta',
-    new ResourceTemplate('chatlab://sessions/{sessionId}/meta', { list: undefined }),
-    { description: '会话元信息（名称、平台、消息数等）' },
-    async (uri, params) => {
-      const sessionId = params.sessionId as string
-      const db = dbManager.open(sessionId)
-      if (!db) {
-        return { contents: [{ uri: uri.href, text: '{"error": "Session not found"}', mimeType: 'application/json' }] }
-      }
-
-      const meta = getSessionMeta(db)
-      const overview = getSessionOverview(db)
-
-      return {
-        contents: [
-          {
-            uri: uri.href,
-            text: JSON.stringify({ ...meta, ...overview }, null, 2),
-            mimeType: 'application/json',
-          },
-        ],
-      }
-    }
-  )
-
-  server.resource(
-    'session-schema',
-    new ResourceTemplate('chatlab://sessions/{sessionId}/schema', { list: undefined }),
-    { description: '会话数据库的表结构' },
-    async (uri, params) => {
-      const sessionId = params.sessionId as string
-      const db = dbManager.open(sessionId)
-      if (!db) {
-        return { contents: [{ uri: uri.href, text: '{"error": "Session not found"}', mimeType: 'application/json' }] }
-      }
-
-      const schema = getDatabaseSchema(db)
-
-      return {
-        contents: [
-          {
-            uri: uri.href,
-            text: JSON.stringify(schema, null, 2),
-            mimeType: 'application/json',
-          },
-        ],
-      }
-    }
-  )
-
-  // --- 启动 stdio 传输 ---
-  const transport = new StdioServerTransport()
-  await server.connect(transport)
+export async function startCliMcpServer(): Promise<void> {
+  const dbManager = initMcpRuntime()
+  await startMcpServer({ version: getVersion(), dbManager })
 }

apps/cli/tsconfig.json

@@ -12,6 +12,7 @@
     "../../packages/config/**/*",
     "../../packages/parser/**/*",
     "../../packages/tools/**/*",
-    "../../packages/sync/**/*"
+    "../../packages/sync/**/*",
+    "../../packages/mcp-server/**/*"
   ]
 }

apps/cli/tsup.config.ts

@@ -13,7 +13,7 @@ export default defineConfig({
   clean: true,
   target: 'node20',
   platform: 'node',
-  noExternal: [/^@openchatlab\//, 'stream-json'],
+  noExternal: [/^@openchatlab\//, 'chatlab-mcp', 'stream-json'],
   external: ['better-sqlite3', '@node-rs/jieba'],
   banner: {
     js: [

apps/desktop/helper/mcp.ts

@@ -0,0 +1,24 @@
+/**
+ * Desktop MCP Helper entry point
+ *
+ * Standalone stdio MCP server that shares the same data directory as
+ * the desktop app. Intended to be invoked by MCP clients (Claude Desktop,
+ * Cursor, etc.) without launching the GUI.
+ *
+ * Dev usage:
+ *   pnpm --filter @openchatlab/desktop run mcp
+ */
+
+import { loadConfig } from '@openchatlab/config'
+import { NodePathProvider, DatabaseManager } from '@openchatlab/node-runtime'
+import { startMcpServer } from 'chatlab-mcp'
+
+const config = loadConfig()
+const userDataDir = config.data.user_data_dir || undefined
+const pathProvider = new NodePathProvider(userDataDir)
+pathProvider.ensureAllDirs()
+const dbManager = new DatabaseManager(pathProvider)
+
+const version = process.env.npm_package_version ?? '0.0.0-dev'
+
+startMcpServer({ version, dbManager })

apps/desktop/package.json

@@ -11,7 +11,8 @@
     "preview": "electron-vite preview",
     "build": "electron-vite build",
     "build:mac": "pnpm run build && electron-builder --mac --config electron-builder.yml -p never",
-    "build:win": "pnpm run build && electron-builder --win --config electron-builder.yml -p never"
+    "build:win": "pnpm run build && electron-builder --win --config electron-builder.yml -p never",
+    "mcp": "tsx helper/mcp.ts"
   },
   "dependencies": {
     "@aptabase/electron": "^0.3.1",
@@ -26,8 +27,10 @@
     "@electron-toolkit/tsconfig": "^1.0.1",
     "@electron/rebuild": "^4.0.4",
     "@types/better-sqlite3": "^7.6.13",
+    "chatlab-mcp": "workspace:*",
     "electron": "35.7.5",
     "electron-builder": "^26.0.12",
-    "electron-vite": "^5.0.0"
+    "electron-vite": "^5.0.0",
+    "tsx": "^4.21.0"
   }
 }

apps/desktop/tsconfig.node.json

@@ -4,6 +4,7 @@
     "electron.vite.config.*",
     "main/**/*",
     "preload/**/*",
+    "helper/**/*",
     "shared/**/*",
     "../../src/types/**/*",
     "../../packages/shared-types/**/*",
@@ -13,7 +14,8 @@
     "../../packages/parser/**/*",
     "../../apps/cli/**/*",
     "../../packages/tools/**/*",
-    "../../packages/sync/**/*"
+    "../../packages/sync/**/*",
+    "../../packages/mcp-server/**/*"
   ],
   "compilerOptions": {
     "composite": true,
@@ -23,7 +25,8 @@
     "paths": {
       "@/*": ["../../src/*"],
       "@electron/*": ["./*"],
-      "@openchatlab/*": ["../../packages/*"]
+      "@openchatlab/*": ["../../packages/*"],
+      "chatlab-mcp": ["../../packages/mcp-server/src"]
     }
   }
 }