# Method Idempotency Classify

> Method Idempotency Classify is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Classifies an HTTP method (GET, POST, PUT, DELETE, etc.) as safe, idempotent, or non-idempotent and returns a deterministic pass/advisory verdict.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/method-idempotency-classify
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/method-idempotency-classify-e5b9411b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_77OXkVfJcF1WtSzIvh5zJ

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 method-idempotency-classify-e5b9411b -d '<json body>'
```

Example prompt: Can you classify the HTTP method 'DELETE' as safe, idempotent, or non-idempotent so I know whether it's safe to retry or cache?

## When to prefer this

Use this endpoint when an agent or API pipeline needs a deterministic, authoritative classification of an HTTP method's idempotency and safety properties before making decisions about caching, retrying, redirecting, or accepting caller-supplied responses. Prefer this over ad-hoc logic when you need a versioned, auditable JSON verdict rather than hardcoded conditionals.

## Known failure modes

- Invalid or unrecognized HTTP method string returns advisory status
- Empty method field results in validation error
- Oversized input beyond 8192 characters rejected
- Payment failure via x402 prevents processing

## How this service works

Method Idempotency Classify: Method Idempotency Classify classifies an HTTP method as safe, idempotent, or non-idempotent from bounded caller-supplied values without an external provider. Call Method Idempotency Classify before accepting, caching, redirecting, or retrying a caller-supplied web response. Returns normalized web evidence, the computed finding, and an explicit pass or advisory status for Method Idempotency Classify as versioned deterministic JSON. Price: $0.001 USDC via x402 on Bas…

## Output

Returns versioned deterministic JSON containing: the normalized HTTP method input as web evidence, the computed idempotency/safety classification (safe, idempotent, or non-idempotent), and an explicit pass or advisory status verdict.

## 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/method-idempotency-classify-e5b9411b/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)