# SignalHarness EVM Log Inventory

> SignalHarness EVM Log Inventory 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 and inventories EVM (Ethereum Virtual Machine) event logs from caller-supplied data, returning a structured log inventory with warnings and evidence scope.

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/evm_log_inventory/invoke
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signalharness-evm-log-inventory-6db293b4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cyJsAgSw8Pzqo5A2VU_KI

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-evm-log-inventory-6db293b4 -d '<json body>'
```

Example prompt: Can you inventory these EVM event logs from my smart contract transaction and tell me what events were emitted and if there are any warnings? Here's the raw log data: [paste log string here].

## When to prefer this

Choose this endpoint when you have raw EVM event log data from an Ethereum-compatible chain and need a structured, cataloged inventory of those logs with warnings — particularly useful for auditing, debugging, or monitoring smart contract interactions on networks like Base. Prefer this over generic log parsers when you need an agent-native, pay-per-call service with a verifiable receipt and result hash.

## Known failure modes

- Input string too short (below 2 characters) or too long (above 65536 characters) returns a validation error
- Malformed or non-EVM log data may produce empty inventory or warnings without useful output
- Payment failure via x402 will block execution and return a 402 response
- Service unavailability returns a failed status in the receipt object

## 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 log_inventory field with the structured catalog of EVM event logs, a list of warnings encountered during analysis, an evidence_scope field indicating the data came from caller-supplied input, and a full execution receipt with payment ID, request ID, latency, and result hash for auditability.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Inventory is limited to caller-supplied log records."
   ],
   "service_id": "evm_log_inventory",
   "log_inventory": "{\"by_address\":{\"0x0000000000000000000000000000000000000001\":2},\"by_topic0\":{\"0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\":1,\"0xbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\":1},\"log_count\":2}",
   "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": "evm_log_inventory",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "9de0b25bbeec2e306b89cf36d03ea46e13c5a82b62af6dd8c8e1ffce78b0e629",
   "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-evm-log-inventory-6db293b4/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)