# SignalHarness Search-to-Answer Evidence Report

> SignalHarness Search-to-Answer Evidence Report is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-15).

Takes caller-supplied data as input, runs a search-to-answer analysis, and returns a structured evidence report with analysis JSON and sourcing warnings.

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/search_to_answer_evidence_report/invoke
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signalharness-search-to-answer-evidence-report-f50bb818
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Ufo5gE05Gf-6oZKnglvNW

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 signalharness-search-to-answer-evidence-report-f50bb818 -d '<json body>'
```

Example prompt: Run a search-to-answer evidence report on this question: 'What are the main regulatory risks facing stablecoin issuers in the US in 2024?' — return the analysis JSON with any evidence warnings included.

## When to prefer this

Choose this endpoint when you need a structured, evidence-backed answer report in machine-readable JSON format, especially when you want sourcing transparency (evidence_scope and warnings fields) and a cryptographically verifiable result (SHA256 receipt). It is well-suited for research automation pipelines where auditability and structured output matter more than raw web scraping. Prefer it over generic LLM Q&A when you need a pay-per-call, receipt-verified evidence synthesis step in an agent workflow.

## Known failure modes

- Malformed or too-short request_json (below minLength:2) causes validation failure
- Request JSON exceeding 65,536 characters is rejected
- Payment not settled on Base network results in 402 response
- Analysis may return warnings indicating caller-supplied data could not be independently verified
- Result may reflect only caller-supplied data scope rather than live web search if external access is unavailable

## How this service works

Explore 330 pay-per-call x402 API services and 27 agent-native digital products, with Base USDC pricing, secure Polar checkout, and free discovery.

## Output

Returns a JSON object containing: an analysis_json field with the structured answer/evidence findings, an evidence_scope field indicating data provenance (e.g. 'caller_supplied_data'), a warnings array flagging reliability caveats, a status field ('succeeded'), and a signed receipt with payment metadata including the USDC amount, network (Base), request and execution IDs, and a SHA256 hash of the result for integrity verification.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "request_json": {
   "type": "string",
   "maxLength": 65536,
   "minLength": 2
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Verify the caller-supplied data before relying on this result."
   ],
   "service_id": "search_to_answer_evidence_report",
   "analysis_json": "{\"example\":\"schema-valid caller-supplied data\"}",
   "evidence_scope": "caller_supplied_data"
  },
  "status": "succeeded",
  "receipt": {
   "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
   "usage": [],
   "status": "succeeded",
   "network": "eip155:8453",
   "artifacts": [],
   "endedAtMs": 0,
   "latencyMs": 0,
   "paymentId": "example-payment",
   "receiptId": "example-receipt",
   "requestId": "example-request",
   "serviceId": "search_to_answer_evidence_report",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "30000",
   "resultSha256": "e09b24a889ee3424898e0f289fe50bb11eee990747a1264b52441dfb60796ca3",
   "serviceVersion": "1.0.0",
   "settlementReference": "0x0000000000000000000000000000000000000000000000000000000000000000"
  },
  "artifacts": [],
  "requestId": "example-request",
  "executionId": "example-execution"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signalharness-search-to-answer-evidence-report-f50bb818/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from signalharness.ai](https://www.zero.xyz/host/signalharness.ai/llms.txt)