# Bounty Engineer Evidence Pack Verifier

> Bounty Engineer Evidence Pack Verifier is a paid API for AI agents from bounty-engineer-x402-prod.onrender.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-12).

Verifies that specific quoted claims are present in caller-supplied source texts, returning per-claim verdicts with byte offsets, freshness info, and a tamper-evident pack hash.

## Facts

- Endpoint: POST https://bounty-engineer-x402-prod.onrender.com/v1/evidence-pack?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/bounty-engineer-evidence-pack-verifier-8a5b297e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NQwn_lf8b8ZkJquS6Pv1J

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 bounty-engineer-evidence-pack-verifier-8a5b297e -d '<json body>'
```

Example prompt: Check whether the quote '$25 per month' actually appears in the source text I scraped from example.com and verify the claim 'Pro is $25 monthly' is supported — give me a tamper-evident evidence pack with the exact offsets and a SHA-256 hash, and flag anything older than 3600 seconds.

## When to prefer this

Choose this endpoint when you need cryptographically attestable, offset-precise proof that a specific quoted string appears in a caller-supplied source document — ideal for AI citation auditing, compliance workflows, or automated fact-checking pipelines where you already have the source text and need a verifiable evidence pack. Prefer alternatives if you need semantic entailment checking (this only checks exact quote presence), independent source fetching, or claim truth evaluation beyond verbatim match.

## Known failure modes

- Claims array is empty or exceeds 40 items — validation error
- Sources array is empty or exceeds 12 items — validation error
- A claim references a source_id not present in the sources array — unmatched source error
- Source text is truncated or differs from live page — quote not found even if claim is true
- max_age_seconds too low for available source timestamps — freshness flagged as stale
- Malformed URI in source URL field — schema validation failure
- Payment of 0.02 USDC not provided via x402 — 402 Payment Required response

## How this service works

Machine-buyable infrastructure for autonomous agents: API cost routing, margin optimization, funding-rate data, webpage extraction, result verification, spend controls, retry planning, state, tender search and GitHub bounty intelligence.

## Output

A JSON object with per-claim verdicts (quote_present, not_found, etc.), UTF-16 start/end offsets of each quote within its source, a SHA-256 of each source text, a top-level pack_sha256 for the entire response, a boolean all_quotes_found, freshness status per claim, and a limitations list clarifying what is and isn't verified.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "claims": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "claim",
     "quote",
     "source_id"
    ],
    "properties": {
     "claim": {
      "type": "string"
     },
     "quote": {
      "type": "string"
     },
     "source_id": {
      "type": "string"
     }
    }
   },
   "maxItems": 40,
   "minItems": 1
  },
  "sources": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "id",
     "url",
     "text"
    ],
    "properties": {
     "id": {
      "type": "string"
     },
     "url": {
      "type": "string",
      "format": "uri"
     },
     "text": {
      "type": "string"
     },
     "fetched_at": {
      "type": "string",
      "format": "date-time"
     }
    }
   },
   "maxItems": 12,
   "minItems": 1
  },
  "max_age_seconds": {
   "type": "integer",
   "maximum": 31536000,
   "minimum": 60
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "mode": "evidence_pack",
  "claims": [
   {
    "claim": "Pro is $25 monthly",
    "index": 0,
    "quote": "$25 per month",
    "verdict": "quote_present",
    "end_utf16": 32,
    "freshness": "unknown",
    "source_id": "s1",
    "quote_found": true,
    "start_utf16": 19,
    "source_sha256": "e03b854ea32bb631569352ed4dfc3541a86da6ec8f82fd1415398f1536fb63dd",
    "declared_age_seconds": null
   }
  ],
  "sources": [
   {
    "id": "s1",
    "url": "https://example.com/",
    "sha256": "e03b854ea32bb631569352ed4dfc3541a86da6ec8f82fd1415398f1536fb63dd",
    "fetched_at": null
   }
  ],
  "limitations": [
   "Checks exact quotation presence in caller-supplied source text, not claim entailment or truth. URLs and timestamps are caller supplied; source authenticity is not independently verified."
  ],
  "pack_sha256": "d104f0d764836b0d6a48dd53e2a10f4b806d8b4738bcb2512a4e0b3b3125d66e",
  "all_quotes_found": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/bounty-engineer-evidence-pack-verifier-8a5b297e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bounty-engineer-x402-prod.onrender.com](https://www.zero.xyz/host/bounty-engineer-x402-prod.onrender.com/llms.txt)