This is a decoder for JSON Web Tokens with an x402 micropayment layer baked in. It exposes tools to inspect JWT headers, payloads, claims, and expiry timestamps without needing to paste tokens into random websites. The repository is pretty bare, just TypeScript source and config files, so you're connecting to a remote endpoint at jwt-decoder.api.klymax402.com rather than running it locally. The x402 integration means you're paying per decode operation, which is an unusual model for what's typically a free utility. Reach for this if you're already in an x402 payment flow and need JWT inspection without context switching, but for casual debugging you'd probably just use jwt.io.
Public tool metadata for what this MCP can expose to an agent.
security_decode_jwtUse this when you need to decode and inspect a JWT token without verifying its signature. Returns the full header, payload, and expiration status. 1. header -- algorithm (RS256, HS256, etc.) and toke1 paramsUse this when you need to decode and inspect a JWT token without verifying its signature. Returns the full header, payload, and expiration status. 1. header -- algorithm (RS256, HS256, etc.) and toke
tokenstring