@mcphero/mcp

MCP transport adapters for MCPHero — expose your actions as MCP tools over stdio, Streamable HTTP, or via a CLI proxy client.

Install

pnpm add @mcphero/core @mcphero/mcp

Adapters

stdio

Standard MCP transport for local tool servers. Communicates over stdin/stdout.

import { mcphero } from '@mcphero/core'
import { stdio } from '@mcphero/mcp'

await mcphero({ name: 'my-tools', description: 'My Tools', version: '1.0.0' })
  .adapter(stdio())
  .action(MyAction)
  .start()

Configure in Claude Desktop or Claude Code:

{
  "mcpServers": {
    "my-tools": {
      "command": "node",
      "args": ["server.js"]
    }
  }
}

http

Session-based MCP transport over HTTP with SSE streaming and resumability.

import { mcphero } from '@mcphero/core'
import { http } from '@mcphero/mcp'

await mcphero({ name: 'my-tools', description: 'My Tools', version: '1.0.0' })
  .adapter(http({ host: 'localhost', port: 8080, allowedHosts: ['localhost'] }))
  .action(MyAction)
  .start()

Exposes POST /mcp (invoke tools), GET /mcp (SSE stream), and DELETE /mcp (terminate session). Built on Express with StreamableHTTPServerTransport from the MCP SDK.

| Option | Type | Description | |--------|------|-------------| | host | string | Bind address | | port | number | Listen port | | allowedHosts | string[] | Allowed hosts for DNS rebinding protection |

cliProxy

MCP CLI proxy client — connects to a running HTTP MCP server and invokes tools from the command line.

import { mcphero } from '@mcphero/core'
import { cliProxy } from '@mcphero/mcp'

await mcphero({ name: 'my-tools', description: 'My Tools', version: '1.0.0' })
  .adapter(cliProxy({ url: 'http://localhost:8080/mcp' }))
  .start()

How Actions Become MCP Tools

| Action property | MCP tool property | |-----------------|-------------------| | name: 'searchDocs' | Tool name: SearchDocs (PascalCase) | | description | Tool description | | input (Zod schema) | inputSchema (JSON Schema) | | Return value | TextContent JSON response | | Thrown errors | Structured error response |

Logging notifications (logger.info(), logger.progress()) are sent to the MCP client as notifications/message and notifications/progress.

See Also

• MCPHero README — Full documentation
• @mcphero/core — Core library
• @mcphero/vercel — Stateless MCP for Vercel