Trust summary

Proof402

Timestamped hash proof for autonomous agents. Lead with verification checks, redaction policy, and proof mechanics before asking an agent to pay.

GET /api/trust GET /api/proofs/{id} GET /api/verify/proofs/{id}

Create proof Inspect trust summary

Verification verified: true

Signature matches the canonical proof payload.

Signed fields proofId timestamp contentHash metadataHash

Redaction no raw payloads metadata keys only recent signatures truncated

Private by default

Agents keep private payloads local and submit only a SHA-256 content hash plus public-safe metadata.

Public verification

Every proof can be checked through a badge page or a machine-readable verification endpoint.

Precise claim

Proof402 proves hash existence at a timestamp, not legal notarization or factual truth.

Agent route

One paid action, two ways to verify.

Paid action

`POST /api/proof/notarize`

Submit a hash, label, optional non-secret metadata, and an idempotency key.

Verification API

`GET /api/verify/proofs/{id}`

Returns signed fields, verification checks, and public proof data.

Public badge

`GET /proof/{id}`

A citable page for the proof without exposing private raw output.

Request shape

Send hashes, not secrets.

The metadata object must stay public-safe. Public surfaces expose metadata hashes and keys, not private payloads.

{
  "contentHash": "sha256:7b3d0f0f7c847c28f20b8c17d38b4f0c7df3da7d8ddfb979a9dd4f9f1f2a35cc",
  "label": "agent result hash",
  "metadata": {
    "agent": "research-bot",
    "taskId": "task_123"
  },
  "idempotencyKey": "proof-task-123"
}