VaultMCP

Keep API keys out of your AI IDE.

VaultMCP is an encrypted secret vault and MCP gateway. You store provider credentials once. Your AI IDE connects to one endpoint. VaultMCP decrypts secrets only when calling upstream MCP servers — your agents and config files never see the raw keys.

Built by Axiler Labs · Product: vaultmcp.dev

Works with any MCP client — Claude Desktop, VS Code, Cursor, Windsurf, Zed, and more.

How it works

One vault. One MCP URL. Every IDE talks to VaultMCP — not to your raw AWS or GitHub keys.

1. Sign in with GitHub and create a workspace on vaultmcp.dev.

2. Store secrets once (encrypted at rest — see Encryption). Share with teammates when needed.

3. Point your IDE at https://vaultmcp.dev/mcp (or your self-hosted /mcp).

4. Call tools like aws__… / github__…. Credentials are injected server-side — never pasted into mcp.json.

flowchart LR
  subgraph clients [MCP clients]
    Claude[Claude]
    VSCode[VS Code]
    Cursor[Cursor]
    Windsurf[Windsurf]
    Zed[Zed]
  end

  subgraph vaultmcp [VaultMCP]
    API[Vault · OAuth · MCP gateway]
  end

  subgraph upstreams [Upstreams]
    MCP[AWS · GitHub · other MCP]
  end

  Claude --> API
  VSCode --> API
  Cursor --> API
  Windsurf --> API
  Zed --> API
  API -->|inject secrets| MCP

Related MCP server: Janee

Features

• Write-only vault — list APIs, MCP responses, and audit logs never return secret values

• Server-side injection — decryption only happens inside the API when calling an upstream

• Private and shared secrets — per-user or workspace-wide visibility

• GitHub OAuth or personal tokens — browser login for IDEs, or vmcp_… tokens in Authorization

• Namespaced tools — register upstreams once; call them as provider__tool_name

• Single public port — Docker Compose exposes port 80; API and UI stay on the internal network

• Optional CLI — inject shared workspace secrets into local npm run dev (and similar) without sharing .env files

Quick start (local)

Need: Node.js 22+, pnpm 9, Docker (Postgres + Redis), and a GitHub OAuth App.

git clone https://github.com/Axiler-Lab/vaultmcp.git
cd vaultmcp
cp .env.example .env

Fill in at least: VAULT_MASTER_KEY, GITHUB_CLIENT_ID, GITHUB_CLIENT_SECRET, PUBLIC_URL, WEB_ORIGIN, DATABASE_URL, REDIS_URL. Local defaults are in .env.example.

GitHub OAuth App

The callback must match PUBLIC_URL.

docker compose up -d postgres redis
pnpm install
pnpm --filter @vaultmcp/shared build
pnpm db:generate   # first time / after schema changes
pnpm db:migrate
pnpm dev:api       # :3001
pnpm dev:web       # :5173

Open http://localhost:5173 → sign in → create a workspace → add secrets → register an upstream (AWS example). Host-run AWS uvx upstreams need uv on your PATH.

Docker Compose

One public entrypoint on port 80. API and web are not published directly.

cp .env.example .env
# Set PUBLIC_URL, WEB_ORIGIN, GITHUB_*, VAULT_MASTER_KEY
# VITE_API_URL=          # empty = same-origin
# COOKIE_SECURE=false    # true behind HTTPS

docker compose up --build

Migrations run when the API container starts. Production notes: docs/DEPLOY.md.

Connect Cursor (or any MCP client)

Same config shape for Cursor, Claude Desktop, VS Code, Windsurf, Zed, and other MCP clients. Use OAuth (browser login) or a personal access token from the dashboard Connect tab. Never put provider secrets in client config.

OAuth (hosted)

{
  "mcpServers": {
    "vaultmcp": {
      "url": "https://vaultmcp.dev/mcp"
    }
  }
}

Personal token (vmcp_… from Connect)

{
  "mcpServers": {
    "vaultmcp": {
      "url": "https://vaultmcp.dev/mcp",
      "headers": {
        "Authorization": "Bearer vmcp_…"
      }
    }
  }
}

Self-host: replace with https://YOUR_HOST/mcp. Local API: http://localhost:3001/mcp.

Cursor: ~/.cursor/mcp.json or .cursor/mcp.json. Other clients use their own MCP config path.

After auth: list_workspaces → use_workspace → call namespaced tools (github__…, aws__…).

Local env CLI (optional)

For shared team secrets in local apps (not MCP agents), use @vaultmcp-axiler/cli:

npx @vaultmcp-axiler/cli@latest login --token vmcp_… --url https://YOUR_HOST
npx @vaultmcp-axiler/cli@latest run -w your-slug -- npm run dev

Create a PAT with the Runtime env (CLI) preset (env scope only). MCP tokens and env tokens are not interchangeable. Prefer run over env so secrets stay in the child process.

Full guide: docs/CLI.md.

Encryption

Secret values are encrypted at rest with AES-256-GCM using envelope encryption:

• Each workspace has its own data encryption key (DEK)

• DEKs are wrapped by VAULT_MASTER_KEY (kept out of the database)

• GCM AAD binds ciphertext to the workspaceId, so blobs cannot be swapped across workspaces

• Decryption happens only server-side — for MCP upstream injection, or opt-in CLI export

• Secret names and other metadata are not encrypted (so the UI can list and authorize without decrypting)

Treat VAULT_MASTER_KEY as a root credential. Rotate provider secrets in the UI without changing IDE config.

Also: list APIs and audit logs never return plaintext values; viewers cannot invoke secret-backed tools or export runtime env.

Details: docs/CRYPTO.md.

Repository layout

apps/api            Gateway, OAuth, REST, upstream proxy
apps/web            Control plane UI
packages/shared     Crypto helpers + shared schemas
packages/cli        Local env injection CLI
deploy/             Reverse proxy config
docs/               Deploy, CLI, and crypto guides
examples/           Upstream walkthroughs

Why AGPL

VaultMCP is often run as a network service. AGPL-3.0-only means if you modify it and offer that service over a network, you must share the corresponding source. That keeps hosted forks honest while still allowing self-hosting and contribution.

Contributing

VaultMCP is an open-source project from Axiler Labs. We’d love help from the community — issues and pull requests are very welcome, especially around security, reliability, docs, and MCP compatibility.

Ways to help:

• Open an issue for bugs or clear feature ideas

• Send a pull request (small, focused changes are easiest to review)

• Improve docs and examples for common upstreams

By contributing, you agree your work is licensed under AGPL-3.0-only, same as the rest of the repo. Never commit secrets; use .env.example for variable names only.

Learn more at vaultmcp.dev · Axiler Labs: axiler.com.

License

Copyright © 2026 Axiler Labs.

VaultMCP is licensed under the GNU Affero General Public License v3.0 only (AGPL-3.0-only).