# AgentProof Timestamp Evidence

> AgentProof Timestamp Evidence is a paid API for AI agents from agentproof.hatchable.site, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-11).

Creates a cryptographic timestamp and integrity receipt for a given piece of content or transaction data, serving as machine-paid tamper-evident proof.

## Facts

- Endpoint: POST https://agentproof.hatchable.site/api/paid/timestamp_evidence?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentproof-timestamp-evidence-5b2afdc2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qvXmjYa6-SIKW4RabB0iA

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agentproof-timestamp-evidence-5b2afdc2 -d '<json body>'
```

Example prompt: Create a tamper-evident timestamp receipt for this document hash — I need cryptographic proof it existed right now and hasn't been altered, including an integrity SHA-256 and a unique receipt ID I can store for audits.

## When to prefer this

Choose this endpoint when an AI agent needs a cryptographically verifiable, machine-paid proof that specific content or transaction data existed at a precise point in time. It is preferable over general logging when tamper-evidence, auditability, and autonomous machine-to-machine trust are required. Ideal for compliance-sensitive autonomous workflows where a UUID-backed integrity receipt needs to be stored or referenced later.

## Known failure modes

- Payment not received or insufficient USDC — returns 402 Payment Required
- Malformed or missing content payload — returns 400 Bad Request
- Service temporarily unavailable — returns 503
- Receipt generation failure — ok:false with error detail
- Hash mismatch if content was corrupted in transit

## How this service works

AgentProof publishes Agent Transaction Passport™ and provides machine-paid evidence, provenance receipts, source comparison and change monitoring for autonomous transactions.

## Output

Returns a JSON object confirming success, the tool name ('timestamp_evidence'), a receipt object containing a unique UUID and a SHA-256 integrity hash of the submitted content, and the service name. This acts as a verifiable, machine-paid proof-of-existence record.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "format": "uri"
  },
  "claim": {
   "type": "string"
  },
  "email": {
   "type": "string"
  },
  "phone": {
   "type": "string"
  },
  "contactName": {
   "type": "string"
  },
  "previousSha256": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "tool": "timestamp_evidence",
  "receipt": {
   "id": "uuid",
   "integrity_sha256": "..."
  },
  "service": "AgentProof"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentproof-timestamp-evidence-5b2afdc2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentproof.hatchable.site](https://www.zero.xyz/host/agentproof.hatchable.site/llms.txt)