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":"8aff9d33b91feba023608396d13863adb3cc7633304bb73e27a5577dd242e0d9","actionTitle":"MSA: Acme AI Labs ↔ GreenLeaf Designs LLC","actionType":"contract_sign","actorHandle":"arivu13_f2d1e0","externalReference":null,"organizationSlug":null,"signatureSlug":"mnav_sig_ovoeoZ9CYIWp","signedAt":"2026-06-02 09:31:46"}
Action payload hash · SHA-256 of the canonical action payload
8aff9d33b91feba023608396d13863adb3cc7633304bb73e27a5577dd242e0d9
Server signature · HMAC-SHA256 over canonical JSON above
802a79304cb27896287b3c5dbd7993d3b6edc56a519bf2d5dd1d1d7df4307c7e
Recompute it yourself
$ printf '%s' '{"actionPayloadHash":"8aff9d33b91feba023608396d13863adb3cc7633304bb73e27a5577dd242e0d9","actionTitle":"MSA: Acme AI Labs ↔ GreenLeaf Designs LLC","actionType":"contract_sign","actorHandle":"arivu13_f2d1e0","externalReference":null,"organizationSlug":null,"signatureSlug":"mnav_sig_ovoeoZ9CYIWp","signedAt":"2026-06-02 09:31:46"}' \
| openssl dgst -sha256 -hmac "$MANAV_SERVER_SIGNING_SECRET" -hex
$ # expected: 802a79304cb27896287b3c5dbd7993d3b6edc56a519bf2d5dd1d1d7df4307c7e