Bitwarden MCP Server

Model Context Protocol (MCP) server that enables interaction with the Bitwarden password manager vault via the MCP protocol. The server allows AI models to securely communicate with a user's Bitwarden vault through defined tool interfaces.

Prerequisites

• Node.js 22
• Bitwarden CLI (bw) installed and authenticated
• Valid Bitwarden session token

Installation

Option One: Configuration in your AI app

Open up your application configuration, e.g. for Claude Desktop:

{
  "mcpServers": {
    "bitwarden": {
      "command": "npx",
      "args": ["-y", "@bitwarden/mcp-server"]
    }
  }
}

Option Two: Local checkout

Requires that this repository be checked out locally. Once that's done:

npm install
npm run build

Setup

1. Install Bitwarden CLI:

   npm install -g @bitwarden/cli

2. Log in to Bitwarden:

   bw login

3. Get session token:

   export BW_SESSION=$(bw unlock --raw)

Testing

Running unit tests

The project includes Jest unit tests covering validation, CLI commands, and core functionality.

# Run all tests
npm test

# Run tests in watch mode
npm run test:watch

# Run tests with coverage
npm test -- --coverage

# Run specific test file
npm test validation.spec.ts

# Run tests matching a pattern
npm test -- --testNamePattern="validation"

Inspection and development

MCP Inspector

Use the MCP Inspector to test the server interactively:

# Start the inspector
npm run inspect

This will:

1. Start the MCP server
2. Launch the inspector UI in your browser
3. Allow you to test all available tools interactively

Available tools

The server provides the following Bitwarden CLI tools:

Tool	Description	Required Parameters
lock	Lock the vault	None
unlock	Unlock with master password	password
sync	Sync vault data	None
status	Check CLI status	None
list	List vault items/folders	type (items/folders/collections/organizations)
get	Get specific item/folder	object, id
generate	Generate password/passphrase	Various optional parameters
create	Create new item or folder	objectType, name, additional fields for items
edit	Edit existing item or folder	objectType, id, optional fields to update
delete	Delete vault item/folder	object, id, optional permanent

Manual testing

1. Start the server:

   export BW_SESSION=$(bw unlock --raw)
   node dist/index.js

2. Test with an MCP client or use the inspector to send tool requests.

Debugging

• Enable debug logging by setting environment variables:

  export DEBUG=bitwarden:*
  export NODE_ENV=development

• Check Bitwarden CLI status:

  bw status

• Verify session token:

  echo $BW_SESSION

Security considerations

• Never commit the BW_SESSION token
• Use environment variables for sensitive configuration
• Validate all inputs using Zod schemas (already implemented)
• Test with non-production data when possible
• Understand the security and privacy impacts of exposing sensitive vault data to LLM and AI tools. Using a self-hosted or local LLM may be appropriate, for example.

Troubleshooting

Common issues

1. "Please set the BW_SESSION environment variable"

   • Run: export BW_SESSION=$(bw unlock --raw)

2. Tests failing with environment errors

   • Use the environment mocking helpers in tests
   • Ensure test cleanup with restoreEnvVars()

3. Inspector not starting

   • Check that the server builds successfully: npm run build
   • Verify Node.js version is 22

4. CLI commands failing

   • Verify Bitwarden CLI is installed: bw --version
   • Check vault is unlocked: bw status
   • Ensure valid session token: echo $BW_SESSION