'pubkey'     the Ed25519 issuer key every signed read verifies against —
             PIN IT OUT OF BAND; a changed key is a changed issuer.
'predicates' the minimal-disclosure catalogue: which banded booleans can be
             attested without handing over the numbers.
'schemas'    the trace + attestation JSON schemas (what you send, what you
             get back signed).
'reversal'   the third-party recompute path — how anyone re-derives a
             profile from the same trace and gets byte-identical output.
'onchain'    every contract of ours, deployed or written-unrun, and how to
             check it yourself.
'anchors'    the inscription register: documents notarized on-chain.
'card'       (default) the service card.

Nothing here is a measurement; it is the apparatus you audit one with.