Verify a receipt
Paste a receipt, drop a receipt file, or open a link that carries one. Your browser checks the Ed25519 signature against the issuer's published keys, follows each link that names a hash to the receipt it cites, and checks each daily root against its AI Source of Truth checkpoint.
Nothing you paste is uploaded. The page fetches only public key sets, inclusion proofs and AI Source of Truth records, and those requests carry only an issuer domain, an id and a hash.
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A verified receipt was signed by the listed key of the domain shown. That says who signed it, not that its contents are true. Outside issuers publish their own keys.