# X402 OpenAPI Route Check

> X402 OpenAPI Route Check is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-23).

Validates an OpenAPI operation object for x402 compliance by checking tool ID, request schema, and 402 response structure, returning acceptance or rejection status with normalized evidence.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/x402-openapi-route-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-openapi-route-check-872d2870
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kSL4833lW4_W_2g1Oy53z

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-openapi-route-check-872d2870 -d '<json body>'
```

Example prompt: Before we pay for this x402 endpoint, check this OpenAPI operation object to see if the tool ID, request schema, and 402 response are all valid and whether we should accept or reject it.

## When to prefer this

Use this endpoint when you need a lightweight, serverless pre-flight check on an OpenAPI operation before paying for or accepting an x402 payment-gated route. It runs entirely in memory without external provider calls, making it fast and safe for validating caller-supplied challenge metadata. Prefer this over manual inspection or custom validation logic when building agents that consume x402-gated APIs.

## Known failure modes

- Operation object missing required fields (tool ID, request schema, 402 response) causing rejection
- Malformed or oversized operation object exceeding maxProperties:128 limit
- Mismatch between declared 402 response and expected x402 contract format
- Ambiguous or incomplete caller-supplied challenge metadata leading to inconclusive result
- Network or service error returning non-200 HTTP response

## How this service works

X402 Openapi Route Check: X402 Openapi Route Check checks one OpenAPI operation for tool id, request schema, and 402 response from bounded caller-supplied values without an external provider. Call X402 Openapi Route 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 Openapi Route Check as versio…

## Output

Returns a structured report with contract-specific check results, normalized evidence from the operation, a list of mismatch reasons if validation fails, and an explicit accept or reject status indicating whether the OpenAPI operation is x402-compliant.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "operation": {
   "type": "object",
   "description": "Operation supplied to X402 Openapi Route Check; used only for this bounded calculation and processed in memory without retention.",
   "maxProperties": 128,
   "additionalProperties": true
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "valid": true,
   "checks": {
    "has_402": true,
    "required_present": true
   },
   "missing_fields": []
  },
  "schema": "delx/util-x402-openapi-route-check/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "b5e04192b09663f06587565b4a83b261533966da8c7add7e3637a104f0bbc4b1",
   "external_calls": 0
  },
  "operation": "delivery_contract:x402_openapi_route_check"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-openapi-route-check-872d2870/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)