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SignalHarness Agent Trace Loop Detector
x402
SignalHarness Agent Trace Loop Detector is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).
Analyzes agent execution trace data to detect loops, cycles, or repetitive patterns in agent reasoning or action sequences.
Price / call$0.01
Success—
StatusUnknown
How this service works
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Output
Returns a JSON result indicating whether a loop was detected (replay boolean), an analysis_json with details about identified patterns, a list of warnings (e.g. to verify caller-supplied data), and an evidence_scope field indicating the data source used. Also includes a full receipt with payment details, latency, and a SHA256 hash of the result.
Example use cases
Debugging a stuck autonomous agent
“My agent seems to be going in circles — can you analyze this trace JSON and tell me if it's caught in a loop? I want to know which steps are repeating.”
Pre-deployment safety check for agent pipeline
“Before I deploy this agent workflow, can you run this execution trace through loop detection to make sure there are no cycles or repetitive patterns I missed?”
Post-incident diagnosis of runaway agent
“We had an incident where our agent ran for way too long and racked up costs — can you analyze this trace log JSON to find where it started looping?”
Technical details
Endpoint
POSThttps://signalharness.ai/api/agent/services/agent_trace_loop_detect/invokeWhen to prefer
Use this endpoint when you need a lightweight, pay-per-call loop detection check on an agent trace without setting up your own monitoring infrastructure. It is well-suited for post-hoc debugging, pre-deployment validation, or real-time safety checks in agent pipelines. Prefer this over manual trace inspection when dealing with complex or long execution histories.
Side effects
- Invalid or malformed request_json payload returns an error
- request_json exceeding 65536 characters is rejected
- Ambiguous or incomplete trace data may yield inconclusive results with warnings
- Payment failure via x402 protocol prevents execution
- Non-JSON string content may cause parsing failures
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| request_json | string |
Output
Schema · Response
{
"type": "json",
"example": {
"replay": false,
"result": {
"warnings": [
"Verify the caller-supplied data before relying on this result."
],
"service_id": "agent_trace_loop_detect",
"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": "agent_trace_loop_detect",
"executionId": "example-execution",
"startedAtMs": 0,
"amountAtomic": "10000",
"resultSha256": "cbe5b25670888073117efc18dddaf6120f9c42b66a2f4e95f801149d9051829b",
"serviceVersion": "1.0.0",
"settlementReference": "0x0000000000000000000000000000000000000000000000000000000000000000"
},
"artifacts": [],
"requestId": "example-request",
"executionId": "example-execution"
}
}Tags
x402
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