# WhatChUNeed Fact Check API

> WhatChUNeed Fact Check API is a paid API for AI agents from whatchuneed.vercel.app, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Verifies claims and checks factual accuracy of a given text input, returning a structured fact-check result.

## Facts

- Endpoint: POST https://whatchuneed.vercel.app/api/verify/factcheck
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/whatchuneed-fact-check-api-384807f6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HYfF3jBtv4BaA6UdgdFiF

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 whatchuneed-fact-check-api-384807f6 -d '<json body>'
```

Example prompt: Can you fact-check this claim for me: 'The Great Wall of China is visible from space with the naked eye'?

## When to prefer this

Choose this endpoint when you need a quick, pay-per-call fact verification without managing a subscription or API key setup. Ideal for agents that occasionally need to validate claims inline during workflows, especially when integrated into x402-compatible payment flows. Suitable for low-volume spot-checking rather than bulk verification pipelines.

## Known failure modes

- Empty or missing 'input' field returns a validation error
- Extremely vague or ambiguous claims may return an unverifiable/inconclusive result
- Claims in obscure languages or domains may produce low-confidence results
- Network timeouts if the backend verification service is slow
- $0.05 USDC payment failure if wallet is underfunded

## How this service works

320+ pay-per-call API endpoints across accommodation, LLM, code execution, crypto, medical, finance, and more. One API, one payment. Powered by x402 protocol.

## Output

Returns a structured result object containing the fact-check outcome (e.g., true, false, misleading, unverified) and supporting details, along with a status field indicating whether the request was processed successfully.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "string",
   "description": "Request input"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "result": {
   "type": "object",
   "description": "Response data"
  },
  "status": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/whatchuneed-fact-check-api-384807f6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from whatchuneed.vercel.app](https://www.zero.xyz/host/whatchuneed.vercel.app/llms.txt)