# AISkills402 Accessibility Review SKILL.md

> AISkills402 Accessibility Review SKILL.md is a paid API for AI agents from api.aiskills402.com, paid per call via x402, $0.03/call, status unknown (last checked 2026-10-14).

Purchases and downloads a tested SKILL.md file for AI agents to perform WCAG accessibility reviews on HTML markup, paid once via x402 in USDC on Base.

## Facts

- Endpoint: GET https://api.aiskills402.com/v1/skills/accessibility-review/file?utm_source=zero.xyz
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/aiskills402-accessibility-review-skill-md-47a5684a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KkptCvuAS-XBb7QRBMQX2

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-accessibility-review-skill-md-47a5684a
```

Example prompt: Buy the accessibility-review SKILL.md from AISkills402 so I can use it to audit my HTML markup for WCAG defects — pay the one-time fee and download the file.

## When to prefer this

Choose this endpoint when you need a pre-tested, versioned SKILL.md instruction file that teaches an AI agent how to identify WCAG accessibility defects in HTML markup, and you want a one-time micropayment model (paid in USDC on Base via x402) with permanent re-download rights rather than a subscription or per-call SaaS API.

## Known failure modes

- Payment not included or insufficient USDC — returns 402 Payment Required
- Invalid or malformed x402 payment header — payment rejected
- Network or settlement failure on Base — transaction not confirmed
- Re-download token expired or invalid on subsequent calls — 401 or 404
- File temporarily unavailable — 503 Service Unavailable

## How this service works

Accessibility Review: WCAG Defects in Markup — Reviews pasted HTML or JSX for the accessibility defects a screen reader or keyboard user hits first, and names the WCAG 2.2 success criterion for each. It flags images without a text alternative, form fields without a label, buttons and links with no accessible name, clickable elements that a keyboard cannot reach, focusable content hidden from assistive technology, personal-data fields without autocomplete, data tables without header cells and pa…

## Output

Returns a JSON object containing the SKILL.md file name and UTF-8 content (the instructions an AI agent uses to perform WCAG accessibility reviews), the skill identifier, a SHA-256 checksum of the file, the version number, a settled x402 payment receipt with the Base transaction hash, and a re-download URL with a unique token 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": "Accessibility Review: WCAG Defects in Markup",
  "skill": "accessibility-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-accessibility-review-skill-md-47a5684a/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)