JWT Hardener decodes any JWT and audits the header and payload for security issues, returning a 0-100 score with severity-tagged findings. Hardened mode outputs a recommended replacement spec with a unified diff from current to ideal. Regression mode compares two tokens and returns structured diffs of new, fixed, and unchanged issues for CI gating.

How to use

1. Paste a JWT — Drop in the full token string, including header, payload, and signature segments.
2. Choose output mode — audit returns findings only. hardened adds a recommended spec with diff. both returns everything.
3. Add compareAgainst (optional) — Paste a second JWT to enable regression mode — see what changed between two token versions.
4. Run the audit — Click Run or press Ctrl+Enter. The score, issue list, and diff appear instantly.
5. Review issues and diff — Critical and high findings should be fixed before issuing the token. The diff shows exact changes.

MCP / API

Call jwt_hardener directly from any MCP-compatible agent:

// MCP TypeScript SDK
const result = await client.callTool({
  name: "jwt_hardener",
  arguments: {
    "token": "..."
  }
});

// curl
curl -X POST https://obfus.link/mcp \
  -H "Authorization: Bearer <SPT>" \
  -H "Content-Type: application/json" \
  -d '{"method":"tools/call","params":{"name":"jwt_hardener","arguments":{"token":"..."}}}'

Related tools

FAQ