# X402 Delivery Hash Check

> X402 Delivery Hash Check is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Verifies delivered text against a caller-supplied SHA-256 digest to accept or reject an x402 agent delivery before payment or acceptance

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/x402-delivery-hash-check
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-delivery-hash-check-c7162846
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_sLHZLrUHQgx1YbITwANjB

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 x402-delivery-hash-check-c7162846 -d '<json body>'
```

Example prompt: Before we accept this delivery and pay, check if the text 'The quarterly report shows 12% revenue growth...' matches the expected SHA-256 hash 'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855' — I need a clear accept or reject with any mismatch reasons.

## When to prefer this

Use this endpoint when you need a deterministic, in-memory, no-retention SHA-256 integrity check on an x402 or agent delivery before paying or accepting — especially when you cannot trust the delivery source and need explicit accept/reject verdicts with mismatch evidence. Prefer this over ad-hoc hashing when you need structured rejection reasons and normalized evidence suitable for audit logs or automated pipeline gates.

## Known failure modes

- Malformed or non-hexadecimal expected_sha256 string returns a validation error
- Text exceeding 8192 characters is rejected with a length constraint error
- Missing required fields (text or expected_sha256) return a 400 bad request
- Hash mismatch returns a rejection status with specific mismatch reasons rather than an error — this is expected behavior
- Extremely large payloads near the limit may add latency

## How this service works

X402 Delivery Hash Check: X402 Delivery Hash Check verifies delivered text against a caller-supplied sha-256 digest from bounded caller-supplied values without an external provider. Call X402 Delivery Hash Check before paying for or accepting an x402 or agent delivery assembled from caller-supplied challenge and result metadata. Returns contract-specific checks, normalized evidence, mismatch reasons, and an explicit acceptance or rejection status for X402 Delivery Hash Check as versioned determ…

## Output

Returns an explicit accept or reject status for the delivery, contract-specific validation checks, normalized evidence about the hash comparison, and detailed mismatch reasons if the computed SHA-256 of the supplied text does not match the expected digest — all as a versioned deterministic response with no external calls or data retention.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string",
   "maxLength": 8192,
   "description": "Text supplied to X402 Delivery Hash Check; used only for this bounded calculation and processed in memory without retention."
  },
  "expected_sha256": {
   "type": "string",
   "maxLength": 8192,
   "description": "Expected Sha256 supplied to X402 Delivery Hash Check; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "matched": false,
   "actual_sha256": "633163569ade0beccda175c1e30d98ad117e7dfb0197ff7889836a9de9d3f823",
   "expected_sha256": "7ef67e6a0c33e752d9848702556ca7c63ce63718b2e62b10d1b1d2386e4db0cc"
  },
  "schema": "delx/util-x402-delivery-hash-check/v1",
  "status": "advisory",
  "evidence": {
   "retained": false,
   "input_sha256": "ba733049f9eb88f065a3f19eafada98c9f92d558213695771252332799ffe285",
   "external_calls": 0
  },
  "operation": "delivery_contract:x402_delivery_hash_check"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-delivery-hash-check-c7162846/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)