Installation

Requirements

• Elysia >=1.4.0
• Node.js >=20.11 or Bun >=1.1
• TypeScript >=5.8 for TypeScript projects
• Native ESM

Install the adapter

npm install @mwillbanks/elysia-mcp-adapter elysia

elysia is a peer dependency. The adapter does not bring another application framework or a full MCP framework into your runtime.

Add the plugin

import { mcp } from '@mwillbanks/elysia-mcp-adapter'
import { Elysia } from 'elysia'

const app = new Elysia().use(mcp())

This installs three fluent methods and registers the MCP HTTP endpoint:

• .mcpTool()
• .mcpResource()
• .mcpPrompt()

The default endpoint is /mcp.

Optional integrations

Install only the integrations your application uses:

npm install @elysia/openapi

npm install @elysiajs/bearer

npm install @elysiajs/opentelemetry

OpenAPI route metadata and schemas are reused by the adapter. Bearer authentication hooks and OpenTelemetry instrumentation remain part of the same Elysia lifecycle. See Route-backed Tools, Security, and Transportation for complete examples.