Vaultwarden MCP

MCP server for Vaultwarden — search, read, and sync vault entries via the Model Context Protocol.

Pure Rust binary using modelcontextprotocol/rust-sdk (MCP v3.0, 2026-07-28 spec). Multi-account support. Stdio and Streamable HTTP transports.

Features

• 🔐 Vault search — find credentials by name, URI, or username
• 📋 Cipher read — retrieve full credential details by ID
• 🔄 Vault sync — refresh cipher cache from Vaultwarden server
• 👥 Multi-account — connect to multiple vaults simultaneously
• 🛡️ Credential verification — HMAC-checked master key derivation on connect (wrong password caught immediately)
• 📡 MCP v3.0 — compliant with the 2026-07-28 protocol spec
• 🚀 Single binary — no runtime dependencies, no Python, no Node.js

Installation

Download (recommended)

Download the latest release binary from GitHub Releases:

# Linux (x86_64)
curl -sL https://github.com/jr2804/vaultwarden-mcp/releases/latest/download/vaultwarden-mcp-linux-x86_64 \
  -o vaultwarden-mcp && chmod +x vaultwarden-mcp

# Linux (ARM64)
curl -sL https://github.com/jr2804/vaultwarden-mcp/releases/latest/download/vaultwarden-mcp-linux-aarch64 \
  -o vaultwarden-mcp && chmod +x vaultwarden-mcp

# macOS (Apple Silicon)
curl -sL https://github.com/jr2804/vaultwarden-mcp/releases/latest/download/vaultwarden-mcp-macos-aarch64 \
  -o vaultwarden-mcp && chmod +x vaultwarden-mcp

# Windows (PowerShell)
Invoke-WebRequest -Uri "https://github.com/jr2804/vaultwarden-mcp/releases/latest/download/vaultwarden-mcp-windows-x86_64.exe" \
  -OutFile vaultwarden-mcp.exe

??? tip "Build from source"

Requires Rust 1.88+. See the [Build guide](build.md) for instructions.

Configuration

Set environment variables to connect to your Vaultwarden server:

export VAULTWARDEN_SERVER="https://vault.example.com"
export VAULTWARDEN_CLIENT_ID="your-client-id"
export VAULTWARDEN_CLIENT_SECRET="your-client-secret"
export VAULTWARDEN_PASSWORD="your-vault-password"
export VAULTWARDEN_ACCOUNT_NAME="my-vault"           # optional, defaults to "default"
export VAULTWARDEN_ALLOW_HTTP="true"                  # only for http:// servers

Multi-account

For multiple vaults, set VAULTWARDEN_ACCOUNTS as a comma-separated list and prefix per-account vars:

export VAULTWARDEN_ACCOUNTS="personal,work"

# Personal vault
export VAULTWARDEN_ACCOUNT_PERSONAL_SERVER="https://personal-vault.example.com"
export VAULTWARDEN_ACCOUNT_PERSONAL_CLIENT_ID="..."
export VAULTWARDEN_ACCOUNT_PERSONAL_CLIENT_SECRET="..."
export VAULTWARDEN_ACCOUNT_PERSONAL_PASSWORD="..."

# Work vault
export VAULTWARDEN_ACCOUNT_WORK_SERVER="https://work-vault.example.com"
export VAULTWARDEN_ACCOUNT_WORK_CLIENT_ID="..."
export VAULTWARDEN_ACCOUNT_WORK_CLIENT_SECRET="..."
export VAULTWARDEN_ACCOUNT_WORK_PASSWORD="..."

MCP Client Setup

Use add-mcp to configure vaultwarden-mcp for any MCP-compatible agent:

npx add-mcp /path/to/vaultwarden-mcp --args "serve --transport stdio" \
  --env VAULTWARDEN_SERVER=https://vault.example.com \
  --env VAULTWARDEN_CLIENT_ID="your-client-id" \
  --env VAULTWARDEN_CLIENT_SECRET="your-client-secret" \
  --env VAULTWARDEN_PASSWORD="your-vault-password"

add-mcp supports Claude Code, Codex, Cursor, OpenCode, VS Code, Gemini CLI, and 17 more agents.

MCP Tools

Tool	Parameters	Description
search	query, account (optional)	Search vault by name, URI, or username
get_cipher	cipher_id, account (optional)	Get full credential details by ID
sync	account (optional)	Refresh cipher cache from server
list_accounts	—	List all connected vault accounts

Usage

# Stdio transport (for MCP clients)
vaultwarden-mcp serve --transport stdio

# HTTP transport (Streamable HTTP at /mcp)
vaultwarden-mcp serve --transport http --host 127.0.0.1 --port 8080

# Show version
vaultwarden-mcp --version

Security

• No plaintext secrets stored — all cipher operations decrypt in-memory only
• Credential verification on connect — wrong password or credential mismatch caught immediately (HMAC check on symmetric key)
• Per-account isolation — separate sessions per vault identity
• No logging of secrets — tracing limited to operation metadata

Documentation

• Architecture — system design, data flow, layer responsibilities
• Build from source — compiling the Rust binary
• Contributing — development workflow, PR guidelines

License

MIT — see LICENSE for details.