About Guardrail MCP
Guardrail MCP is a small, read-only remote service for deterministic preflight checks. It flags selected risks in proposed actions without executing them, storing requests, or calling AI.
Key features
- 01Credential exposure detection
- 02Fund movement detection
- 03External write detection
- 04Instruction override detection
- 05Deterministic risk assessment
Use cases
- 01Checking an action before exposing credentials
- 02Reviewing a proposed funds transfer
- 03Preflighting an external write
- 04Flagging instruction overrides
MCP support
Exposes `get_guardrail_capabilities` and `assess_action_risk` through stateless Streamable HTTP at `/mcp`.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://guardrail-mcp.kadopi.workers.dev/mcpclaude mcp add --transport http kadopi-guardrail https://guardrail-mcp.kadopi.workers.dev/mcp{"mcpServers":{"kadopi-guardrail":{"type":"http","url":"https://guardrail-mcp.kadopi.workers.dev/mcp"}}}Open in Cursor{"servers":{"kadopi-guardrail":{"type":"http","url":"https://guardrail-mcp.kadopi.workers.dev/mcp"}}}Open in VS Code{"mcpServers":{"kadopi-guardrail":{"type":"http","url":"https://guardrail-mcp.kadopi.workers.dev/mcp"}}}{"mcpServers":{"kadopi-guardrail":{"serverUrl":"https://guardrail-mcp.kadopi.workers.dev/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
2This tool takes no parameters.
Details
From the project READMEGuardrail MCP
Small, free, read-only Remote MCP for deterministic action preflight.
It exposes two tools:
get_guardrail_capabilitiesassess_action_risk
The check detects a deliberately small set of high-risk patterns: credential exposure, fund movement, external writes, and instruction overrides. It does not execute an action, persist a request, authenticate a user, charge a payment, call AI, or fetch external URLs.
Local use
npm run check
npm test
npm run dev
Endpoints: GET /, GET /health, and stateless Streamable HTTP POST /mcp.
Boundary
This is an informational deterministic preflight, not a safety guarantee or legal, financial, or security advice. Deployment and any public endpoint require separate approval.
Comments
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