Firebase Emulator MCP Server

A Model Context Protocol server that exposes Firebase emulator data — Firestore, Auth, Logs, and Realtime Database — to AI agents over stdio.

Designed for local development workflows where AI coding assistants (Claude Code, GitHub Copilot, etc.) need to inspect emulator state without leaving the editor.

Created by Laish Glenberg, please drop a star on the repo if this package helped you!

Features

Related MCP server: Firebase MCP Server

Prerequisites

• Node.js 18+ (native fetch and WebSocket — v21+ recommended)

• Firebase emulators running locally — start from your project root:

  firebase emulators:start

  The server connects to the default emulator ports:

  • Firestore: 8080

  • Auth: 9099

  • Realtime Database: 9000

  • Hub (logs): 4500

Install & Run

Via npm (recommended)

npm install -g firebase-emulator-mcp
firebase-emulator-mcp

VS Code / MCP Client Setup

Add to your project's .vscode/mcp.json or VS Code user settings:

{
  "servers": {
    "firebase-emulator": {
      "type": "stdio",
      "command": "node",
      "args": ["./mcp-server/lib/index.js"],
      "env": {
        "FIREBASE_PROJECT_ID": "<proj_id>",
        "FIREBASE_RTDB_NAMESPACE": "<proj_id>-default-rtdb"
      }
    }
  }
}

Or if installed globally:

{
  "servers": {
    "firebase-emulator": {
      "type": "stdio",
      "command": "firebase-emulator-mcp",
      "env": {
        "FIREBASE_PROJECT_ID": "<proj_id>",
        "FIREBASE_RTDB_NAMESPACE": "<proj_id>-default-rtdb"
      }
    }
  }
}

Optionally can skip install and run directly through npx

{
  "servers": {
    "firebase-emulator": {
      "type": "stdio",
      "command": "npx",
      "args": ["@lglen/firebase-emulator-mcp"],
      "env": {
        "FIREBASE_PROJECT_ID": "<proj_id>",
        "FIREBASE_RTDB_NAMESPACE": "<proj_id>-default-rtdb"
      }
    }
  }
}

For Claude Code or other MCP clients, use the same stdio configuration.

Project structure

mcp-server/
├── src/
│   └── index.ts          # TypeScript source (all tools)
├── lib/                   # Compiled output (git-ignored)
├── test.mjs              # Smoke test runner
├── tsconfig.json
├── package.json
├── .gitignore
├── LICENSE               # MIT
└── README.md

Configuration

Default emulator ports are defined in src/index.ts under the EMULATORS constant. Edit them to match your firebase.json if you use non-standard ports:

License

MIT

Author

Check me out on GitHub