# SignalHarness ABI Event Decoder

> SignalHarness ABI Event Decoder 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).

Decodes Ethereum ABI-encoded smart contract events from raw log data into human-readable form

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/abi_event_decode/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-abi-event-decoder-2b0e78ed
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_47popTOCeEwwM8adtKGff

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-abi-event-decoder-2b0e78ed -d '<json body>'
```

Example prompt: Decode this raw Ethereum ABI-encoded event log for me — I pulled it from a transaction receipt on Base and need to know what the event fields and values actually are: 0x000000000000000000000000...

## When to prefer this

Choose this endpoint when you need a quick, pay-per-call ABI event decoding service with cryptographic receipt proof (SHA-256 result hash) and structured output, especially within agent workflows on Base network that already use x402 micropayment infrastructure. It is well suited for one-off event decoding without managing your own ABI parsing infrastructure.

## Known failure modes

- Malformed or truncated ABI-encoded input returns a decode error
- Missing or invalid ABI definition causes field mapping failure
- Input string below minimum length (2 chars) is rejected with validation error
- Non-ABI-encoded data submitted will produce garbled or warning-laden output
- Network or service unavailability returns a non-succeeded status

## 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 decoded event object with human-readable field names and values extracted from the ABI-encoded input, along with any warnings about the data, an evidence scope tag indicating the data came from caller-supplied input, and a full receipt including payment ID, network, latency, execution ID, and a SHA-256 result hash for verification.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Decoded logs are not independently verified receipts."
   ],
   "service_id": "abi_event_decode",
   "decoded_event": "{\"args\":{\"account\":\"0x0000000000000000000000000000000000000001\",\"value\":\"5\"},\"eventName\":\"Changed\"}",
   "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": "abi_event_decode",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "71cc9e37ca3a7b3db01eef23c28b210412f3c573ffcd524467a49e448bb59dbe",
   "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-abi-event-decoder-2b0e78ed/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)