MCP bridge (bidirectional)

Consume any MCP server as AgentsKit tools, or expose your AgentsKit tools to MCP hosts — over stdio or any transport.

Model Context Protocol (MCP) is the emerging open standard for connecting LLM hosts (Claude Desktop, Cursor, Zed, IDEs) to external tool servers. @agentskit/tools/mcp ships a minimal bidirectional bridge — consume MCP servers as AgentsKit tools, and expose your AgentsKit tools to any MCP host.

This is a protocol subset: initialize + tools/list + tools/call over JSON-RPC 2.0. Full MCP (resources, prompts, sampling) is a follow-up.

Install

npm install @agentskit/tools

Transports are framework-agnostic — bring your own stdio, WebSocket, or SSE + POST. An in-memory transport pair ships for tests.

Consume an MCP server

import { spawn } from 'node:child_process'
import {
  createMcpClient,
  createStdioTransport,
  toolsFromMcpClient,
} from '@agentskit/tools/mcp'
import { createRuntime } from '@agentskit/runtime'

const child = spawn('my-mcp-server', ['--flag'], { stdio: ['pipe', 'pipe', 'inherit'] })
const transport = createStdioTransport(child)
const client = createMcpClient({ transport })
await client.initialize()

const tools = await toolsFromMcpClient(client)
const runtime = createRuntime({ adapter, tools })

// Later:
await client.close()

toolsFromMcpClient advertises every MCP tool as a native ToolDefinition — schemas pass through, errors propagate, results are flattened from the MCP content[] array into a single string.

Publish AgentsKit tools as an MCP server

import { createMcpServer, createStdioTransport } from '@agentskit/tools/mcp'
import { webSearch, fetchUrl } from '@agentskit/tools'

const transport = createStdioTransport(process as unknown as {
  stdin: typeof process.stdin
  stdout: typeof process.stdout
  on?: typeof process.on
})

createMcpServer({
  transport,
  tools: [webSearch(), fetchUrl()],
  serverInfo: { name: 'my-agentskit-mcp', version: '1.0.0' },
  onEvent: e => console.error('[mcp]', e),
})

Your process now speaks MCP on stdin/stdout. Point Claude Desktop, Cursor, or any MCP host at the binary and your AgentsKit tools show up as first-class.

Transports

Transport	Provider
`createStdioTransport(child)`	newline-delimited JSON over stdin/stdout
`createInMemoryTransportPair()`	paired in-process transports — tests, in-process bridges
Your own	implement the `McpTransport` contract (`send` + `onMessage` + optional `onClose` + `close`) — WebSocket, SSE + POST, etc.

MCP bridge (bidirectional)

Install

Consume an MCP server

Publish AgentsKit tools as an MCP server

Transports

See also

On this page