# SiteCheck Text Answer (QA over provided text)

> SiteCheck Text Answer (QA over provided text) is a paid API for AI agents from api.sitecheck-api.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-20).

Answers a natural-language question using only the supplied text as the source, returning a model-written answer with verified exact-substring quotes.

## Facts

- Endpoint: POST https://api.sitecheck-api.workers.dev/api/text/answer?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sitecheck-text-answer-qa-over-provided-text-261cc0cb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_sHzuQcnOB556LzKwj3WdY

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 sitecheck-text-answer-qa-over-provided-text-261cc0cb -d '<json body>'
```

Example prompt: Using only this contract text I'm pasting, answer the question: 'What is the notice period for termination?' — and show me the exact quote from the document that supports your answer.

## When to prefer this

Choose this endpoint when you need to answer a specific question grounded strictly in a user-supplied text corpus, with verifiable exact-substring citations — not web search, not external knowledge. Ideal for contract analysis, policy lookups, document QA, and any scenario where hallucination must be minimized by constraining the model to the provided source. Prefer over generic LLM chat when auditability and quote verification matter.

## Known failure modes

- Text exceeds 30,000 character limit — request rejected or truncated
- Question exceeds 500 character limit — request rejected
- 'answerable' returns false if the question cannot be answered from the supplied text
- Quotes may be dropped (quotesDropped > 0) if they cannot be verified as exact substrings
- Empty or missing 'text' or 'question' fields cause validation errors
- Payment failure (x402) if USDC balance is insufficient

## How this service works

Answers a question from the given text only (max 30,000 characters), with supporting quotes and their character offsets. Each quote is checked against the text and dropped if it does not occur in it. answerable is false when the text does not contain the answer. Model output: verify before relying on it.

## Output

A JSON object containing the model-written answer to the question, one or more exact-substring quotes (each with start and end character offsets) from the source text that support the answer, an 'answerable' boolean indicating whether the question could be resolved from the text, the timestamp the check was performed, and a count of any quotes that were dropped.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string",
   "description": "The only source for the answer (max 30,000 characters)"
  },
  "question": {
   "type": "string",
   "description": "Question to answer (max 500 characters)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "note": "Quotes are verified as exact substrings of the text; the answer itself is model-written.",
  "answer": "40 euros a year",
  "quotes": [
   {
    "end": 55,
    "quote": "The membership fee is 40 euros a year, paid in January.",
    "start": 0
   }
  ],
  "question": "What does the text say the fee is?",
  "checkedAt": "2026-10-15T18:21:09.358Z",
  "answerable": true,
  "quotesDropped": 0
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sitecheck-text-answer-qa-over-provided-text-261cc0cb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.sitecheck-api.workers.dev](https://www.zero.xyz/host/api.sitecheck-api.workers.dev/llms.txt)