Schema validation itself is a solved problem available in every language for free. What is not free is proving afterwards that a payload was valid at a point in time, when the party who needs convincing is not the party who ran the check. That is the case this serves: an agent asserting it validated something is worth little, and a signed attestation that a third party can verify independently is worth something. Whether you need that depends entirely on whether anyone downstream has reason to doubt the caller — inside your own pipeline, a library does the job.
A JSON Schema validator that issues cryptographic attestations: validate produces a signed record of the result, verify checks the signature, and get_attestation retrieves a stored one by id.
- validate checks a payload against a JSON Schema and returns a signed attestation rather than a bare pass or fail.
- verify confirms the signature on an attestation, so the result can be checked by someone who was not there when it ran.
- get_attestation retrieves a stored attestation in full by its id.
RAPIDTOOLS_API_KEY.
One command plus a key — npx -y @tailoredtools/mcp-server, then supply credentials