Stranger verifier

Drop a certificate in. This page checks it and tells you one of three things. It is a single file: no server, no runtime download, no network request of any kind — disconnect and it still works.

Drop a file here, or — one file, nothing else to set up.
no document yet

Three answers, and the third is not a polite second

ACCEPTthis verifier checked the document and it holds
REJECTthis verifier checked the document and it does not hold
REFUSEthis verifier did not check it, and the reason code says why. It is not a statement about the document: another project's valid certificate lands here, and so does a certificate naming a specification this page does not carry.

A Farkas certificate names the specification it was issued against by fingerprint. This page carries 7 published specifications and checks a certificate against the one it names — never against something convenient. An unknown fingerprint is refused; a fingerprint swapped for another specification this page does hold is rejected.

Optional: the outcome trace

Only needed to re-derive a decoder-audit certificate's Merkle root. Without it the root is reported as not checked, never as passing.