Drupal Bridge MCP Server

🚀 Quick Start

Related MCP server: MCP OpenAPI Connector

🛠️ Available Tools

MCP tools are auto-discovered from the Drupal site. Just create the tools using JSON-RPC MCP.

How It Works

1. Server fetches tool definitions from /mcp/tools/list

2. Extracts required OAuth scopes from each tool's annotations.auth.scopes

This eliminates manual scope configuration and automatically adapts to backend tool changes.

Automatic Scope Discovery

Scopes are extracted from tool metadata:

{
  "name": "examples.contentTypes.create",
  "annotations": {
    "auth": {
      "scopes": ["content_type:write"],
      "level": "required"
    }
  }
}

The server automatically requests the content_type:write scope during OAuth flow.

Tool Access Validation

Before invoking a tool, the server validates:

1. Authentication - Tool requires auth and session is authenticated

2. Scopes - Session has all required OAuth scopes

3. Permissions - Drupal validates permissions server-side

Error example:

Insufficient OAuth scopes for tool "examples.contentTypes.create".
Required: content_type:write
Missing: content_type:write
Current: profile, content_type:read

Authentication Levels

Tools can declare three authentication levels:

• none: Public tools, no authentication required

• optional: Enhanced functionality with auth, but works without

• required: Enforces authentication and scope validation

If a tool doesn't declare annotations.auth, it defaults to level='none' (public access).

📋 Development

# Install dependencies
npm install

# Run in development
npm run dev

# Build for production
npm run build

# Type check
npm run type-check

Use the great MCP Inspector project to validate the MCP server changes.

npx @modelcontextprotocol/inspector

📄 License

MIT

👨‍💻 Author

Mateu Aguiló Bosch (e0ipso) mateu@mateuaguilo.com