# Color Contrast Checker

> Color Contrast Checker is a paid API for AI agents from x402-toolbox.shablony-pro.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-02).

Checks the contrast ratio between two colors and returns WCAG accessibility compliance results

## Facts

- Endpoint: GET https://x402-toolbox.shablony-pro.workers.dev/util/color-contrast-checker?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/color-contrast-checker-4c466cc4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_d0sk_N59BNOFsirmZKK2x

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 color-contrast-checker-4c466cc4
```

Example prompt: Can you check if white text (#FFFFFF) on a dark blue background (#003087) passes WCAG contrast requirements?

## When to prefer this

Choose this endpoint when you need a fast, deterministic, no-signup color contrast check payable per-call with USDC over Base. Ideal for AI agents doing automated accessibility audits or design validation workflows where spinning up an API key is impractical.

## Known failure modes

- Invalid or malformed color values in the schema parameter may return an error
- Missing required color parameters may result in a failed computation
- Non-hex color formats may not be supported
- Payment failure via x402 will block access to the result

## How this service works

309 deterministic pay-per-call tools for AI agents over x402 (USDC, Base). No signup, no API key: the payment is the identity.

## Output

Returns a JSON object with ok and paid flags, and likely includes the computed contrast ratio value and WCAG compliance levels (AA, AAA) for normal and large text sizes based on the provided color inputs.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "schema": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "paid": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/color-contrast-checker-4c466cc4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-toolbox.shablony-pro.workers.dev](https://www.zero.xyz/host/x402-toolbox.shablony-pro.workers.dev/llms.txt)