feat(server): implement MCP Server with stdio transport

Phase 2.2: add chatlab mcp command that starts an MCP stdio server.
Registers 8 tools from @openchatlab/tools and 3 resources (sessions
list, session meta, session schema). Compatible with Claude Desktop
and Cursor MCP client configuration.

packages/server/package.json

@@ -17,6 +17,8 @@
     "@openchatlab/config": "workspace:*",
     "@openchatlab/node-runtime": "workspace:*",
     "@openchatlab/shared-types": "workspace:*",
+    "@modelcontextprotocol/sdk": "^1.12.1",
+    "@openchatlab/tools": "workspace:*",
     "commander": "^13.1.0"
   },
   "devDependencies": {

packages/server/src/cli.ts

@@ -198,6 +198,15 @@ program
     dbManager.closeAll()
   })
 
+// chatlab mcp - MCP Server
+program
+  .command('mcp')
+  .description('启动 MCP Server（stdio 传输，供 Claude Desktop / Cursor 等 AI 代理使用）')
+  .action(async () => {
+    const { startMcpServer } = await import('./mcp')
+    await startMcpServer()
+  })
+
 // chatlab config - 配置管理
 const configCmd = program.command('config').description('配置管理')
 

packages/server/src/mcp.ts

@@ -0,0 +1,212 @@
+/**
+ * ChatLab MCP Server
+ *
+ * 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。
+ */
+
+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, DatabaseManager } from '@openchatlab/node-runtime'
+import {
+  getSessionMeta,
+  getSessionOverview,
+  getDatabaseSchema,
+} from '@openchatlab/core'
+import { TOOL_REGISTRY } from '@openchatlab/tools'
+import type { SessionListContext } from '@openchatlab/tools/src/definitions/sessions'
+
+let dbManager: DatabaseManager
+
+function initMcpRuntime() {
+  const config = loadConfig()
+  const dataDir = config.data.dir || undefined
+  const pathProvider = new NodePathProvider(dataDir)
+  pathProvider.ensureAllDirs()
+  dbManager = new DatabaseManager(pathProvider)
+  return { config, dbManager }
+}
+
+/**
+ * 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: '0.0.1',
+  })
+
+  // --- 注册 Tools ---
+
+  for (const tool of TOOL_REGISTRY) {
+    if (tool.name === 'chatlab_sessions') {
+      const zodShape = jsonSchemaToZod(tool.inputSchema.properties, tool.inputSchema.required)
+
+      server.tool(
+        tool.name,
+        tool.description,
+        zodShape,
+        async (params) => {
+          const context: SessionListContext = {
+            db: null as any,
+            sessionId: '',
+            listSessionIds: () => dbManager.listSessionIds(),
+            openDb: (id) => dbManager.open(id),
+          }
+          const result = tool.handler(params as Record<string, unknown>, context)
+          return { content: [{ type: 'text' as const, text: result.content }] }
+        }
+      )
+      continue
+    }
+
+    // 其他工具：注入 session_id 参数
+    const zodShape = {
+      session_id: z.string().describe('会话 ID（通过 chatlab_sessions 工具获取）'),
+      ...jsonSchemaToZod(tool.inputSchema.properties, tool.inputSchema.required),
+    }
+
+    server.tool(
+      tool.name,
+      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 = tool.handler(toolParams, { db, sessionId })
+        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)
+}