diff --git a/cli/src/utils/auth.ts b/cli/src/utils/auth.ts
index 7d81f48ef9..cbf7ae9daa 100644
--- a/cli/src/utils/auth.ts
+++ b/cli/src/utils/auth.ts
@@ -14,8 +14,8 @@ import type { CiEnv } from '@codebuff/common/types/contracts/env'
 // User schema
 const userSchema = z.object({
   id: z.string().optional(),
-  name: z.string(),
-  email: z.string(),
+  name: z.string().nullish(),
+  email: z.string().nullish(),
   authToken: z.string(),
   fingerprintId: z.string().optional(),
   fingerprintHash: z.string().optional(),
diff --git a/common/src/mcp/__tests__/client-pool.test.ts b/common/src/mcp/__tests__/client-pool.test.ts
new file mode 100644
index 0000000000..c19c979df9
--- /dev/null
+++ b/common/src/mcp/__tests__/client-pool.test.ts
@@ -0,0 +1,89 @@
+import { describe, expect, it } from 'bun:test'
+
+import { MCPClientPool } from '../client-pool'
+
+type Config = { id: string }
+type FakeClient = { id: string }
+
+describe('MCPClientPool', () => {
+  it('deduplicates concurrent connections and reports ready status', async () => {
+    let connects = 0
+    const pool = new MCPClientPool<FakeClient, Config>({
+      keyOf: (config) => config.id,
+      connect: async (config) => {
+        connects++
+        await Bun.sleep(5)
+        return { id: config.id }
+      },
+      close: async () => {},
+    })
+
+    const [first, second] = await Promise.all([
+      pool.get({ id: 'docs' }),
+      pool.get({ id: 'docs' }),
+    ])
+
+    expect(connects).toBe(1)
+    expect(first.client).toBe(second.client)
+    expect(pool.statuses()).toEqual([
+      expect.objectContaining({ id: 'docs', state: 'ready' }),
+    ])
+  })
+
+  it('removes failed connections so the next request can retry', async () => {
+    let attempts = 0
+    const pool = new MCPClientPool<FakeClient, Config>({
+      keyOf: (config) => config.id,
+      connect: async (config) => {
+        attempts++
+        if (attempts === 1) throw new Error('offline')
+        return { id: config.id }
+      },
+      close: async () => {},
+    })
+
+    await expect(pool.get({ id: 'retry' })).rejects.toThrow('offline')
+    expect((await pool.get({ id: 'retry' })).client.id).toBe('retry')
+    expect(attempts).toBe(2)
+  })
+
+  it('closes one or every live client', async () => {
+    const closed: string[] = []
+    const pool = new MCPClientPool<FakeClient, Config>({
+      keyOf: (config) => config.id,
+      connect: async (config) => ({ id: config.id }),
+      close: async (client) => {
+        closed.push(client.id)
+      },
+    })
+
+    await pool.get({ id: 'one' })
+    await pool.get({ id: 'two' })
+    expect(await pool.close('one')).toBe(true)
+    await pool.closeAll()
+
+    expect(closed.sort()).toEqual(['one', 'two'])
+    expect(pool.statuses()).toEqual([])
+  })
+
+  it('times out a stalled connection and allows a later retry', async () => {
+    let shouldHang = true
+    const pool = new MCPClientPool<FakeClient, Config>(
+      {
+        keyOf: (config) => config.id,
+        connect: async (config) => {
+          if (shouldHang) await new Promise(() => {})
+          return { id: config.id }
+        },
+        close: async () => {},
+      },
+      { connectTimeoutMs: 10 },
+    )
+
+    await expect(pool.get({ id: 'slow' })).rejects.toThrow(
+      'MCP connection timed out',
+    )
+    shouldHang = false
+    expect((await pool.get({ id: 'slow' })).client.id).toBe('slow')
+  })
+})
diff --git a/common/src/mcp/client-pool.ts b/common/src/mcp/client-pool.ts
new file mode 100644
index 0000000000..da63481613
--- /dev/null
+++ b/common/src/mcp/client-pool.ts
@@ -0,0 +1,125 @@
+export type MCPClientPoolStatus = {
+  id: string
+  state: 'connecting' | 'ready'
+  connectedAt: number | null
+  lastUsedAt: number
+}
+
+type MCPClientPoolAdapter<TClient, TConfig> = {
+  keyOf: (config: TConfig) => string
+  connect: (config: TConfig) => Promise<TClient>
+  close: (client: TClient) => Promise<void>
+}
+
+type MCPClientPoolOptions = {
+  connectTimeoutMs?: number
+}
+
+type PoolEntry<TClient> = {
+  client: TClient | null
+  connecting: Promise<TClient>
+  connectedAt: number | null
+  lastUsedAt: number
+}
+
+export function withTimeout<T>(
+  promise: Promise<T>,
+  timeoutMs: number,
+  message: string,
+): Promise<T> {
+  if (timeoutMs <= 0) return promise
+
+  let timeout: ReturnType<typeof setTimeout> | undefined
+  const rejection = new Promise<never>((_, reject) => {
+    timeout = setTimeout(() => reject(new Error(message)), timeoutMs)
+  })
+  return Promise.race([promise, rejection]).finally(() => {
+    if (timeout) clearTimeout(timeout)
+  })
+}
+
+/**
+ * Reuses MCP transports across turns and owns their complete lifecycle.
+ * Concurrent callers for the same config share one handshake.
+ */
+export class MCPClientPool<TClient, TConfig> {
+  private readonly entries = new Map<string, PoolEntry<TClient>>()
+  private readonly connectTimeoutMs: number
+
+  constructor(
+    private readonly adapter: MCPClientPoolAdapter<TClient, TConfig>,
+    options: MCPClientPoolOptions = {},
+  ) {
+    this.connectTimeoutMs = options.connectTimeoutMs ?? 30_000
+  }
+
+  async get(config: TConfig): Promise<{ id: string; client: TClient }> {
+    const id = this.adapter.keyOf(config)
+    const existing = this.entries.get(id)
+    if (existing) {
+      existing.lastUsedAt = Date.now()
+      return { id, client: existing.client ?? (await existing.connecting) }
+    }
+
+    const now = Date.now()
+    const rawConnection = this.adapter.connect(config)
+    const connecting = withTimeout(
+      rawConnection,
+      this.connectTimeoutMs,
+      `MCP connection timed out after ${this.connectTimeoutMs}ms`,
+    )
+    const entry: PoolEntry<TClient> = {
+      client: null,
+      connecting,
+      connectedAt: null,
+      lastUsedAt: now,
+    }
+    this.entries.set(id, entry)
+
+    try {
+      const client = await connecting
+      entry.client = client
+      entry.connectedAt = Date.now()
+      entry.lastUsedAt = entry.connectedAt
+      return { id, client }
+    } catch (error) {
+      if (this.entries.get(id) === entry) this.entries.delete(id)
+      // A timed-out transport can still finish later. Close it instead of
+      // leaking a child process or socket no caller can reach.
+      rawConnection.then(this.adapter.close).catch(() => {})
+      throw error
+    }
+  }
+
+  getReady(id: string): TClient | undefined {
+    const entry = this.entries.get(id)
+    if (!entry?.client) return undefined
+    entry.lastUsedAt = Date.now()
+    return entry.client
+  }
+
+  statuses(): MCPClientPoolStatus[] {
+    return [...this.entries.entries()]
+      .map(([id, entry]) => ({
+        id,
+        state: entry.client ? ('ready' as const) : ('connecting' as const),
+        connectedAt: entry.connectedAt,
+        lastUsedAt: entry.lastUsedAt,
+      }))
+      .sort((a, b) => a.id.localeCompare(b.id))
+  }
+
+  async close(id: string): Promise<boolean> {
+    const entry = this.entries.get(id)
+    if (!entry) return false
+    this.entries.delete(id)
+    const client = entry.client ?? (await entry.connecting.catch(() => null))
+    if (client) await this.adapter.close(client)
+    return true
+  }
+
+  async closeAll(): Promise<void> {
+    const ids = [...this.entries.keys()]
+    await Promise.allSettled(ids.map((id) => this.close(id)))
+  }
+}