# AISkills402 SKILL.md Review File Download

> AISkills402 SKILL.md Review File Download is a paid API for AI agents from api.aiskills402.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-27).

Downloads the SKILL.md file for the 'SKILL.md Review' skill after payment via x402, returning the file content, version, and a redownload token.

## Facts

- Endpoint: GET https://api.aiskills402.com/v1/skills/skill-md-review/file?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-27
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/aiskills402-skill-md-review-file-download-fcfef9c9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DsvU53hzDV3AWptvChh7j

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 aiskills402-skill-md-review-file-download-fcfef9c9
```

Example prompt: Buy and download the SKILL.md Review skill from AISkills402 — I want the actual SKILL.md file content, the SHA256 hash, and the redownload token so I can use it again later.

## When to prefer this

Choose this endpoint when an AI agent needs a tested, versioned SKILL.md file specifically for reviewing and validating other SKILL.md documents, and the agent operates in an x402-enabled payment environment using USDC on Base. It is the right choice when you want a one-time purchase with permanent redownload rights rather than a subscription or per-call fee for repeated access.

## Known failure modes

- Payment not included or insufficient — x402 payment challenge returned, agent must retry with correct USDC payment on Base
- Invalid HTTP method — only GET and HEAD are accepted
- Network or server error — endpoint unavailable, agent should retry
- Payment settled but file delivery failed — agent should use the redownload token to retry retrieval
- Expired or invalid redownload token — redownload URL no longer valid

## How this service works

SKILL.md Review: Safe and Within the Limits — Reviews a SKILL.md file before you install, buy or publish it and lists every problem with a fixed code, the place and a fix, then gives one verdict. It checks the front matter against the published limits (name up to 64 characters in lowercase, hyphens and digits, no reserved words; description present, up to 1,024 characters, naming both its job and the requests that should trigger it, in the third person), and it reads the body for hidden orders …

## Output

Returns a JSON object containing: the SKILL.md file name and UTF-8 content, the skill identifier ('skill-md-review'), a SHA256 hash of the file, the current version string (e.g. '1.0.0'), a payment receipt with the on-chain settlement transaction hash and settled status, and a redownload URL and token (64 hex characters) for future free re-downloads.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "file": {
   "name": "SKILL.md",
   "content": "<the SKILL.md file>",
   "encoding": "utf-8"
  },
  "name": "SKILL.md Review: Safe and Within the Limits",
  "skill": "skill-md-review",
  "sha256": "<sha256 of SKILL.md>",
  "receipt": {
   "tx": "0x<settlement transaction>",
   "settled": true
  },
  "version": "1.0.0",
  "redownload": {
   "url": "<api>/v1/purchases/<token>",
   "token": "<64 hex chars>"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/aiskills402-skill-md-review-file-download-fcfef9c9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.aiskills402.com](https://www.zero.xyz/host/api.aiskills402.com/llms.txt)