# SignalHarness Multi-Agent Trace Compare

> SignalHarness Multi-Agent Trace Compare is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.015/call, status unknown (last checked 2026-09-15).

Compares and analyzes execution traces from multiple AI agents to surface differences, warnings, and behavioral insights.

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/multi_agent_trace_compare/invoke
- Price: $0.015/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signalharness-multi-agent-trace-compare-8ff067cb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DZ8-A7wf3qcI-F0A7WtRr

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-multi-agent-trace-compare-8ff067cb -d '<json body>'
```

Example prompt: I ran the same task through two different agent configurations and want to understand where they diverged — can you compare these execution traces and flag any warnings or behavioral differences?

## When to prefer this

Choose this endpoint when you need to programmatically compare execution traces from two or more AI agents, especially for debugging behavioral regressions, auditing multi-agent coordination, or running A/B evaluations of agent configurations. It is particularly useful when you want a structured analysis with explicit warnings and evidence provenance rather than a manual diff. Prefer this over general-purpose LLM analysis when you need a receipted, pay-per-call service with verifiable output hashes.

## Known failure modes

- Malformed or invalid JSON in request_json field returns a validation error
- Caller-supplied data that cannot be parsed as agent traces may yield low-confidence or empty analysis
- Oversized payloads exceeding 65536 characters are rejected
- Missing or incomplete trace data may result in warnings about insufficient evidence scope
- Network or payment settlement failures may cause execution to not complete

## 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 analysis object containing a comparison of the submitted agent traces, any warnings about the data (e.g. caller-supplied data caveats), an evidence_scope field indicating data provenance, and a structured analysis_json with findings. Also includes a full receipt with payment metadata, execution IDs, latency, and a SHA-256 result hash for 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": "multi_agent_trace_compare",
   "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": "multi_agent_trace_compare",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "15000",
   "resultSha256": "f9b89e88c5feed8adccd165ccc339508f0c307332e99386015a9dd568ba81e5c",
   "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-multi-agent-trace-compare-8ff067cb/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)