Quick Start

1. Create a Config File

bunx open-mcp-guardrails init

This generates guardrails.config.ts:

import { defineConfig, pii, secrets } from "open-mcp-guardrails";

export default defineConfig({
  rules: [
    pii().block(),
    secrets().block(),
  ],
});

Zero-Config

Calling defineConfig() with no arguments enables PII + secret protection by default:

export default defineConfig();

2. Validate Your Config

bunx open-mcp-guardrails check
# Config is valid.
#   Rules: pii-error, secrets-error

3. Start the Proxy

bunx open-mcp-guardrails -- \
  bunx @modelcontextprotocol/server-filesystem /tmp

guardrails.config.ts in the current directory is auto-discovered. Everything before -- is for guardrails, everything after is the original MCP server command.

Next Steps

• Claude Desktop — Integrate with Claude Desktop
• Configuration — Detailed config options
• Rules — Available rule types