# SignalHarness Log Bloom Check

> SignalHarness Log Bloom Check is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Analyzes caller-supplied log data for anomalies, warnings, and replay indicators using bloom-filter-style detection

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/log_bloom_check/invoke
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signalharness-log-bloom-check-4ac0aede
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_sZ9fk8ZQvWoHVZtVmTUiq

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-log-bloom-check-4ac0aede -d '<json body>'
```

Example prompt: Can you run a log bloom check on this log entry to see if it's a replay and flag any warnings: 'ERROR 2024-01-15T12:34:56Z service=auth user=123 msg=login_failed attempt=5'?

## When to prefer this

Choose this endpoint when you need lightweight, fast bloom-filter-style analysis of log strings to detect replay events or surface warnings, especially within agent pipelines that pay per-call via x402/USDC. Prefer it over full log aggregation platforms when you want a single-call, structured answer about a specific log entry without ingesting into a full SIEM or observability stack.

## Known failure modes

- Empty or too-short log_bloom_request (below 2 characters) returns validation error
- Input exceeding 65536 characters is rejected
- Malformed JSON in request body returns parse error
- Payment failure or insufficient USDC balance prevents execution
- Network or service timeout returns no result

## 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 a replay boolean flag indicating whether the log entry appears to be a replay, a list of warnings found in the log data, the evidence scope (caller_supplied_data), the raw bloom check result string, and a full payment receipt with execution metadata including latency, payment ID, and a SHA-256 hash of the result.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Bloom matches are probabilistic and may be false positives."
   ],
   "service_id": "log_bloom_check",
   "evidence_scope": "caller_supplied_data",
   "log_bloom_check": "{\"all_possibly_present\":false,\"results\":[{\"bit_indexes\":[1128,128,1585],\"possibly_present\":false,\"value\":\"0x0000000000000000000000000000000000000001\"}]}"
  },
  "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": "log_bloom_check",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "b965d7e98b49eeb6d6a1ea52d81a93198b70c97e1541c5f6cbe7eae31c6c2fdb",
   "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-log-bloom-check-4ac0aede/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)