# Bounty Engineer Agent Evidence Loop

> Bounty Engineer Agent Evidence Loop 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).

Monitors one or two URLs for content changes, storing a SHA-256 baseline and comparing subsequent fetches to detect modifications — part of an agent-commerce infrastructure suite.

## Facts

- Endpoint: POST https://bounty-engineer-x402-prod.onrender.com/v1/agent-evidence-loop?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-agent-evidence-loop-4a3279eb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__wzyzngqDzmADv1Yg20t8

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-agent-evidence-loop-4a3279eb -d '<json body>'
```

Example prompt: Keep an eye on https://example.com/bounties for me — use watch ID 'bounty-watch-001' under my namespace key 'ns_abcdefghijklmnopqrstuvwxyz' and let me know if the page content changes from the baseline you recorded.

## When to prefer this

Choose this endpoint when an autonomous agent needs to detect content changes on 1–2 specific URLs over time, storing a cryptographic baseline for future comparison. It is purpose-built for agent workflows that require evidence of change (e.g. bounty updates, policy pages, grant deadlines) and integrates with the x402 micropayment protocol, making it suitable for agent-to-agent commerce pipelines where each monitoring call is billed at $0.02 USDC.

## Known failure modes

- Invalid or unreachable source URL returns an error or partial result
- namespace_key shorter than 24 characters or watch_id out of pattern causes schema validation failure
- Polling faster than min_interval_seconds (600s) may return stale or rate-limited responses
- More than 2 source URLs rejected due to maxItems constraint
- Payment failure (x402) blocks the request before execution

## 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

Returns a JSON object with an 'ok' boolean, mode string ('agent_evidence_loop'), a 'changed' field (null on first call), an array of source objects each containing the URL and its SHA-256 content hash plus a 'changed_since_previous' flag, a 'baseline_created' boolean indicating whether this was the first snapshot, a 'comparison_available' boolean, and a 'min_interval_seconds' value (600) indicating the minimum polling interval.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "sources": {
   "type": "array",
   "items": {
    "type": "string",
    "format": "uri"
   },
   "maxItems": 2,
   "minItems": 1
  },
  "watch_id": {
   "type": "string",
   "pattern": "^[A-Za-z0-9][A-Za-z0-9_.:-]{0,79}$",
   "maxLength": 80,
   "minLength": 1
  },
  "namespace_key": {
   "type": "string",
   "maxLength": 256,
   "minLength": 24
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "mode": "agent_evidence_loop",
  "changed": null,
  "sources": [
   {
    "url": "https://example.com/",
    "content_sha256": "0000000000000000000000000000000000000000000000000000000000000000",
    "changed_since_previous": null
   }
  ],
  "baseline_created": true,
  "comparison_available": false,
  "min_interval_seconds": 600
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/bounty-engineer-agent-evidence-loop-4a3279eb/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)