# Delx Commerce — HTTP Method Idempotency Classifier

> Delx Commerce — HTTP Method Idempotency Classifier is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Classifies an HTTP method string as idempotent or non-idempotent and safe or unsafe, with cryptographic evidence of no data retention.

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/method-idempotency-classify?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-commerce-http-method-idempotency-classifier-8aa71178
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SlvP9AcXmmTQepDH7Yt2S

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 delx-commerce-http-method-idempotency-classifier-8aa71178 -d '<json body>'
```

Example prompt: Is PUT idempotent and safe according to HTTP standards? I want to know before I add retry logic to my API client.

## When to prefer this

Choose this endpoint when you need a deterministic, verifiable, pay-per-call classification of HTTP method idempotency with cryptographic proof of no data retention — particularly useful in agent pipelines that need auditable, stateless utility calls without signing up for a service. Prefer over a static lookup table when you need the evidence payload (input hash, external call count) for compliance or logging purposes.

## Known failure modes

- Missing or empty 'method' field returns a validation error
- Malformed JSON body returns a 400-level error
- Unrecognized or non-standard HTTP method strings may return safe:false and idempotent:false as a conservative default
- Payment not received or insufficient USDC balance blocks the call via x402 protocol

## How this service works

Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.

## Output

Returns a JSON object with: whether the method is safe (boolean), whether it is idempotent (boolean), the method name echoed back, the operation schema identifier, a pass/fail status, and cryptographic evidence including an SHA-256 hash of the input and confirmation that no external calls were made and no data was retained.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "method": {
   "type": "string",
   "maxLength": 8192,
   "description": "Method supplied to Method Idempotency Classify; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "safe": false,
   "method": "PUT",
   "idempotent": true
  },
  "schema": "delx/util-method-idempotency-classify/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "c8f1d9636636150613283c76e75ed08a7999d0390f4e3478ee82fa118fcaef20",
   "external_calls": 0
  },
  "operation": "web_reliability:method_idempotency_classify"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-http-method-idempotency-classifier-8aa71178/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from commerce.delx.ai](https://www.zero.xyz/host/commerce.delx.ai/llms.txt)