Manav signed the canonical JSON below with its server secret. Hash the JSON with HMAC-SHA256 using the MANAV_SERVER_SIGNING_SECRET and compare - if it matches, this proof is authentic.
Canonical proof JSON
{"actionPayloadHash":"090e925c76d606d3f0f7c6a168ddb748203d0b19e0e896b775a193f4a94cbcc7","actionTitle":"MSA: Acme AI Labs ↔ GreenLeaf Designs LLC","actionType":"contract_sign","actorHandle":null,"externalReference":null,"organizationSlug":null,"signatureSlug":"mnav_sig_wZS5pe5HBq3L","signedAt":"2026-06-02 10:39:18"}
Action payload hash · SHA-256 of the canonical action payload
090e925c76d606d3f0f7c6a168ddb748203d0b19e0e896b775a193f4a94cbcc7
Server signature · HMAC-SHA256 over canonical JSON above
baaf22542d3e7e36368c24f35e1c76619172b2708a817dbf4efd09cd372430d0
Recompute it yourself
$ printf '%s' '{"actionPayloadHash":"090e925c76d606d3f0f7c6a168ddb748203d0b19e0e896b775a193f4a94cbcc7","actionTitle":"MSA: Acme AI Labs ↔ GreenLeaf Designs LLC","actionType":"contract_sign","actorHandle":null,"externalReference":null,"organizationSlug":null,"signatureSlug":"mnav_sig_wZS5pe5HBq3L","signedAt":"2026-06-02 10:39:18"}' \
| openssl dgst -sha256 -hmac "$MANAV_SERVER_SIGNING_SECRET" -hex
$ # expected: baaf22542d3e7e36368c24f35e1c76619172b2708a817dbf4efd09cd372430d0