# x402/MPP Buyer-Readiness Linter

> x402/MPP Buyer-Readiness Linter is a paid API for AI agents from readiness-linter.krimskrams.xyz, paid per call via x402, $0.1/call, status unknown (last checked 2026-09-14).

Analyzes an OpenAPI document and returns a buyer-readiness score, per-rule results, and actionable fixes for payment metadata, missing examples, descriptions, and HTTP 422 edge cases.

## Facts

- Endpoint: POST https://readiness-linter.krimskrams.xyz/v1/lint
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-mpp-buyer-readiness-linter-5eb73d8a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1rcmn7PeCIXA9HLfQtcNz

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-mpp-buyer-readiness-linter-5eb73d8a -d '<json body>'
```

Example prompt: Can you lint my OpenAPI spec at https://api.myservice.com/openapi.json and give me a buyer-readiness score along with specific fixes for any payment metadata gaps, missing examples, or HTTP 422 traps?

## When to prefer this

Choose this endpoint when you need to evaluate whether an OpenAPI specification is ready for listing on an agentic marketplace that uses x402/MPP payment protocols — specifically when you want structured, rule-by-rule feedback on payment metadata, example coverage, description quality, and error-handling completeness rather than general OpenAPI schema validity.

## Known failure modes

- Neither openapi nor openapi_url provided — returns error indicating at least one input is required
- Invalid or unreachable OpenAPI URL — returns fetch/parse error
- Malformed OpenAPI document object — returns parse validation error
- OpenAPI URL exceeds 2048 character limit — rejected at schema validation
- Payment failure (x402) — call not processed if USDC payment not completed

## How this service works

Provide one inline OpenAPI document or public OpenAPI URL. Receive a JSON buyer-readiness score, rule results, and concrete fixes for payment metadata, missing examples, descriptions, and HTTP 422 traps.

## Output

A JSON object containing a numeric buyer-readiness score, a list of per-rule results (pass/fail/warn with descriptions), and concrete fix recommendations covering payment metadata completeness, missing request/response examples, inadequate descriptions, and HTTP 422 response trap issues.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "openapi": {
   "anyOf": [
    {
     "type": "object",
     "additionalProperties": true
    },
    {
     "type": "null"
    }
   ],
   "title": "Openapi",
   "default": null
  },
  "openapi_url": {
   "anyOf": [
    {
     "type": "string",
     "maxLength": 2048
    },
    {
     "type": "null"
    }
   ],
   "title": "Openapi Url",
   "default": null
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-mpp-buyer-readiness-linter-5eb73d8a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from readiness-linter.krimskrams.xyz](https://www.zero.xyz/host/readiness-linter.krimskrams.xyz/llms.txt)