# SignalHarness ABI Custom Error Decoder

> SignalHarness ABI Custom Error Decoder is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Decodes a custom Solidity ABI error from raw revert data into a human-readable form, given caller-supplied ABI and error payload

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/abi_custom_error_decode/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-abi-custom-error-decoder-29307dff
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YurtDTtzUmvcwmQgD4-0V

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-custom-error-decoder-29307dff -d '<json body>'
```

Example prompt: I got a custom error revert from my smart contract — can you decode this raw ABI error data for me: '{"abi": [...], "data": "0x1234abcd..."}'?

## When to prefer this

Choose this endpoint when you need to programmatically decode Solidity custom errors from raw ABI-encoded revert data on EVM-compatible chains, especially on Base. It is purpose-built for agent workflows that encounter contract reverts and need machine-readable decoded error output with a verifiable receipt. Prefer it over generic ABI libraries when you need a paid, auditable, receipt-backed decode as part of an on-chain agent pipeline.

## Known failure modes

- Malformed or invalid ABI definition causes decode failure
- Error selector in data does not match any entry in the supplied ABI
- Input string exceeds 65536 character limit
- Truncated or corrupted hex revert data produces ambiguous decode
- Missing required abi_error_decode_request field returns validation error
- Payment failure or insufficient USDC balance prevents execution

## 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 with a decoded_custom_error string (human-readable error name and arguments), optional warnings array, service_id, evidence_scope indicating the data came from caller-supplied input, and a full payment receipt including network, asset, amounts, latency, and execution identifiers.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Decoded revert data does not prove transaction execution."
   ],
   "service_id": "abi_custom_error_decode",
   "evidence_scope": "caller_supplied_data",
   "decoded_custom_error": "{\"abiItem\":{\"inputs\":[{\"name\":\"available\",\"type\":\"uint256\"}],\"name\":\"Insufficient\",\"type\":\"error\"},\"args\":[\"5\"],\"errorName\":\"Insufficient\"}"
  },
  "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_custom_error_decode",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "4beeae711d524731f74ce28b2ba6eb1cc6582faab0517b7748b025bebcc57737",
   "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-custom-error-decoder-29307dff/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)