Firebase MCP

Overview

Firebase MCP enables AI assistants to work directly with Firebase services, including:

• Firestore: Document database operations
• Storage: File management with robust upload capabilities
• Authentication: User management and verification

The server works with MCP client applicatios such as Claude Desktop, Augment Code, VS Code, and Cursor.

⚠️ Known Issue: The firestore_list_collections tool may return a Zod validation error in the client logs. This is an erroneous validation error in the MCP SDK, as our investigation confirmed no boolean values are present in the response. Despite the error message, the query still works correctly and returns the proper collection data. This is a log-level error that doesn't affect functionality.

⚡ Quick Start

Prerequisites

• Firebase project with service account credentials
• Node.js environment

1. Install MCP Server

Add the server configuration to your MCP settings file:

• Claude Desktop: ~/Library/Application Support/Claude/claude_desktop_config.json
• Augment: ~/Library/Application Support/Code/User/settings.json
• Cursor: [project root]/.cursor/mcp.json

MCP Servers can be installed manually or at runtime via npx (recommended). How you install determines your configuration:

Configure for npx (recommended)

{
  "firebase-mcp": {
    "command": "npx",
    "args": [
      "-y",
      "@gannonh/firebase-mcp"
    ],
    "env": {
      "SERVICE_ACCOUNT_KEY_PATH": "/absolute/path/to/serviceAccountKey.json",
      "FIREBASE_STORAGE_BUCKET": "your-project-id.firebasestorage.app"
    }
  }
}

Configure for local installation

{
  "firebase-mcp": {
    "command": "node",
    "args": [
      "/absolute/path/to/firebase-mcp/dist/index.js"
    ],
    "env": {
      "SERVICE_ACCOUNT_KEY_PATH": "/absolute/path/to/serviceAccountKey.json",
      "FIREBASE_STORAGE_BUCKET": "your-project-id.firebasestorage.app"
    }
  }
}

2. Test the Installation

Ask your AI client: "Please test all Firebase MCP tools."

🛠️ Setup & Configuration

1. Firebase Configuration

1. Go to Firebase Console → Project Settings → Service Accounts
2. Click "Generate new private key"
3. Save the JSON file securely

2. Environment Variables

Required

• SERVICE_ACCOUNT_KEY_PATH: Path to your Firebase service account key JSON (required)

Optional

• FIREBASE_STORAGE_BUCKET: Bucket name for Firebase Storage (defaults to [projectId].appspot.com)
• MCP_TRANSPORT: Transport type to use (stdio or http) (defaults to stdio)
• MCP_HTTP_PORT: Port for HTTP transport (defaults to 3000)
• MCP_HTTP_HOST: Host for HTTP transport (defaults to localhost)
• MCP_HTTP_PATH: Path for HTTP transport (defaults to /mcp)
• DEBUG_LOG_FILE: Enable file logging:
  • Set to true to log to ~/.firebase-mcp/debug.log
  • Set to a file path to log to a custom location

3. Client Integration

Claude Desktop

Edit: ~/Library/Application Support/Claude/claude_desktop_config.json

VS Code / Augment

Edit: ~/Library/Application Support/Code/User/settings.json

Cursor

Edit: [project root]/.cursor/mcp.json

📚 API Reference

Firestore Tools

Storage Tools

Authentication Tools

💻 Developer Guide

Installation & Building

git clone https://github.com/gannonh/firebase-mcp
cd firebase-mcp
npm install
npm run build

Running Tests

First, install and start Firebase emulators:

npm install -g firebase-tools
firebase init emulators
firebase emulators:start

Then run tests:

# Run tests with emulator
npm run test:emulator

# Run tests with coverage
npm run test:coverage:emulator

Project Structure

src/
├── index.ts                  # Server entry point
├── utils/                    # Utility functions
└── lib/
    └── firebase/              # Firebase service clients
        ├── authClient.ts     # Authentication operations
        ├── firebaseConfig.ts   # Firebase configuration
        ├── firestoreClient.ts # Firestore operations
        └── storageClient.ts  # Storage operations

🌐 HTTP Transport

Firebase MCP now supports HTTP transport in addition to the default stdio transport. This allows you to run the server as a standalone HTTP service that can be accessed by multiple clients.

Running with HTTP Transport

To run the server with HTTP transport:

# Using environment variables
MCP_TRANSPORT=http MCP_HTTP_PORT=3000 node dist/index.js

# Or with npx
MCP_TRANSPORT=http MCP_HTTP_PORT=3000 npx @gannonh/firebase-mcp

Client Configuration for HTTP

When using HTTP transport, configure your MCP client to connect to the HTTP endpoint:

{
  "firebase-mcp": {
    "url": "http://localhost:3000/mcp"
  }
}

Session Management

The HTTP transport supports session management, allowing multiple clients to connect to the same server instance. Each client receives a unique session ID that is used to maintain state between requests.

🔍 Troubleshooting

Common Issues

Storage Bucket Not Found

If you see "The specified bucket does not exist" error:

1. Verify your bucket name in Firebase Console → Storage
2. Set the correct bucket name in FIREBASE_STORAGE_BUCKET environment variable

Firebase Initialization Failed

If you see "Firebase is not initialized" error:

1. Check that your service account key path is correct and absolute
2. Ensure the service account has proper permissions for Firebase services

Composite Index Required

If you receive "This query requires a composite index" error:

1. Look for the provided URL in the error message
2. Follow the link to create the required index in Firebase Console
3. Retry your query after the index is created (may take a few minutes)

Zod Validation Error with firestore_list_collections

If you see a Zod validation error with message "Expected object, received boolean" when using the firestore_list_collections tool:

⚠️ Known Issue: The firestore_list_collections tool may return a Zod validation error in the client logs. This is an erroneous validation error in the MCP SDK, as our investigation confirmed no boolean values are present in the response. Despite the error message, the query still works correctly and returns the proper collection data. This is a log-level error that doesn't affect functionality.

Debugging

Enable File Logging

To help diagnose issues, you can enable file logging:

# Log to default location (~/.firebase-mcp/debug.log)
DEBUG_LOG_FILE=true npx @gannonh/firebase-mcp

# Log to a custom location
DEBUG_LOG_FILE=/path/to/custom/debug.log npx @gannonh/firebase-mcp

You can also enable logging in your MCP client configuration:

{
  "firebase-mcp": {
    "command": "npx",
    "args": ["-y", "@gannonh/firebase-mcp"],
    "env": {
      "SERVICE_ACCOUNT_KEY_PATH": "/path/to/serviceAccountKey.json",
      "FIREBASE_STORAGE_BUCKET": "your-project-id.firebasestorage.app",
      "DEBUG_LOG_FILE": "true"
    }
  }
}

Real-time Log Viewing

To view logs in real-time:

# Using tail to follow the log file
tail -f ~/.firebase-mcp/debug.log

# Using a split terminal to capture stderr
npm start 2>&1 | tee logs.txt

Using MCP Inspector

The MCP Inspector provides interactive debugging:

# Install MCP Inspector
npm install -g @mcp/inspector

# Connect to your MCP server
mcp-inspector --connect stdio --command "node ./dist/index.js"

📋 Response Formatting

Storage Upload Response Example