# Document Answer with Verified Quotes

> Document Answer with Verified Quotes is a paid API for AI agents from market.datapackvibe.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-21).

Answers a question grounded in up to three supplied text passages and returns exact supporting quotes verified to exist in the input.

## Facts

- Endpoint: POST https://market.datapackvibe.com/x402/assistant-grounded-document-answer?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/document-answer-with-verified-quotes-00143935
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MgLrUALwgRz5uUNFyEQyf

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 document-answer-with-verified-quotes-00143935 -d '<json body>'
```

Example prompt: Using only these passages I'm giving you — 'Refunds can be requested within thirty days. Support opens Monday to Friday from 09:00 to 17:00.' — answer the question 'What is the refund period?' and include an exact supporting quote from the text.

## When to prefer this

Choose this endpoint when you need a grounded, citation-backed answer derived strictly from text you supply, not from web search or model training knowledge. It is ideal for document QA, contract review, policy interpretation, or any task where auditability and exact sourcing matter. Prefer it over general-purpose LLMs when you need quote verification and a closed-context guarantee. It is not suitable for open-domain questions requiring web retrieval.

## Known failure modes

- Question not answerable from supplied passages — model may indicate insufficient information
- Passage too long — each passage is capped at 400 characters, longer inputs will be rejected
- More than 3 passages submitted — array is limited to maxItems 3
- Empty question or passage — minLength 1 enforced on both fields
- Payment failure — x402 payment of 0.01 USDC required per call
- Hallucinated quote — entailment accuracy is not fully guaranteed, only quote existence is checked

## How this service works

Document Answer with Verified Quotes: Answer a question using up to three short supplied passages and include exact supporting quotes. Quote existence is checked; answer entailment still requires review. No web search. 0.01 USDC includes one question with up to 3 passages.

## Output

A direct answer to the submitted question, derived solely from the provided passages, along with exact verbatim quotes from those passages that support the answer. Quote existence within the supplied text is verified; entailment quality may still vary.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "question": {
   "type": "string",
   "default": "What is the refund period?",
   "maxLength": 300,
   "minLength": 1
  },
  "documents": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 400,
    "minLength": 1
   },
   "default": [
    "Refunds can be requested within thirty days. Support opens Monday to Friday from 09:00 to 17:00."
   ],
   "maxItems": 3,
   "minItems": 1
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/document-answer-with-verified-quotes-00143935/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from market.datapackvibe.com](https://www.zero.xyz/host/market.datapackvibe.com/llms.txt)