# CAPI2 Momentum Foundry – Integrity Receipt

> CAPI2 Momentum Foundry – Integrity Receipt is a paid API for AI agents from capi2-foundry.vandurmedries.workers.dev, paid per call via x402, $0.006/call, status unknown (last checked 2026-10-11).

Hashes a JSON payload and returns a cryptographically signed delivery receipt proving what input was submitted, what result was produced, and that payment was settled via x402.

## Facts

- Endpoint: POST https://capi2-foundry.vandurmedries.workers.dev/v1/products/integrity-receipt/run?utm_source=zero.xyz
- Price: $0.006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/capi2-momentum-foundry-integrity-receipt-509a8b69
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lbgPt--qylE3BCCXRGRbI

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 capi2-momentum-foundry-integrity-receipt-509a8b69 -d '<json body>'
```

Example prompt: Hash this JSON object and give me a signed integrity receipt proving what I submitted and what came back: {"orderId": "ORD-9921", "amount": 250, "currency": "USD", "status": "confirmed"}.

## When to prefer this

Choose this endpoint when you need a cryptographically verifiable, payment-linked receipt proving the exact JSON payload submitted and result returned — ideal for audit trails, compliance logging, agent accountability, or any workflow where you need tamper-evident proof that a specific input produced a specific output and that a micro-payment was made. Prefer alternatives if you only need a local hash (no payment or delivery proof required) or if your payload exceeds 100,000 characters.

## Known failure modes

- Payment not verified — x402 settlement must complete before the endpoint processes the request
- Payload too large — input JSON exceeds 100,000 serialized characters, returning a validation error
- Malformed JSON input — non-JSON or invalid `data` field causes a 400-level error
- Network/worker timeout — Cloudflare Worker may time out under load
- Duplicate or replayed payment — stale or reused payment headers may be rejected

## How this service works

Paid agent utilities delivered after verified x402 settlement.

## Output

Returns a JSON object containing: a `result` field (the computed output), a `createdAt` timestamp, the `productId`, and a `deliveryReceipt` object with the payer's wallet address, a unique `receiptId` (UUID v4), `deliveredAt` timestamp, `inputSha256` (hash of submitted data), `amountAtomic` (payment in atomic USDC units, e.g. 6000 = $0.006), `resultSha256` (hash of the result), and `signatureSha256` (hash of the combined receipt signature).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "description": "JSON value to hash; at most 100000 serialized characters"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {},
  "createdAt": "2026-09-23T00:00:00.000Z",
  "productId": "integrity-receipt",
  "deliveryReceipt": {
   "payer": "0x0000000000000000000000000000000000000000",
   "productId": "integrity-receipt",
   "receiptId": "00000000-0000-4000-8000-000000000000",
   "deliveredAt": "2026-09-23T00:00:00.000Z",
   "inputSha256": "example-input-sha256",
   "amountAtomic": "6000",
   "resultSha256": "example-result-sha256",
   "signatureSha256": "example-signature-sha256"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/capi2-momentum-foundry-integrity-receipt-509a8b69/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from capi2-foundry.vandurmedries.workers.dev](https://www.zero.xyz/host/capi2-foundry.vandurmedries.workers.dev/llms.txt)