# SignalHarness EIP-2612 Permit Inspector

> SignalHarness EIP-2612 Permit Inspector 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).

Inspects and validates EIP-2612 permit data (gasless token approval signatures) supplied by the caller, returning warnings and a structured analysis of the permit's contents and safety.

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/permit_inspect_eip2612/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-eip-2612-permit-inspector-d47af750
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_esVj9qWs-nhISikbIg2Zj

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-eip-2612-permit-inspector-d47af750 -d '<json body>'
```

Example prompt: Before I sign this permit, can you inspect it for me and flag any warnings or red flags? Here's the permit data: {permit JSON or hex string}.

## When to prefer this

Choose this endpoint when an AI agent or user needs to programmatically audit an EIP-2612 gasless token approval permit before signing — especially to detect replay risks, suspicious spender addresses, abnormal deadlines, or other red flags. Prefer this over generic smart-contract analysis tools when the specific input is an EIP-2612 permit structure and you need structured warnings and a replay flag in a single low-cost call ($0.01 USDC).

## Known failure modes

- Invalid or malformed permit data causes processing failure
- permit_inspection_request below minimum length (2 chars) returns validation error
- Oversized input exceeding 65536 characters rejected
- Payment failure on x402 channel results in 402 response before execution
- Unsupported permit format not conforming to EIP-2612 may yield incomplete inspection

## 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 top-level 'result' containing a 'permit_inspection' summary string, a list of 'warnings', the 'evidence_scope' (e.g. 'caller_supplied_data'), and a 'replay' boolean indicating replay-attack risk. Also includes a full execution receipt with payment details, latency, and a SHA-256 hash of the result for auditability.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Inspection does not verify nonce, signature, balance, or allowance state."
   ],
   "service_id": "permit_inspect_eip2612",
   "evidence_scope": "caller_supplied_data",
   "permit_inspection": "{\"deadline\":\"2000000000\",\"expired_at_ms\":false,\"nonce\":\"1\",\"owner\":\"0x0000000000000000000000000000000000000001\",\"source\":\"fields\",\"spender\":\"0x0000000000000000000000000000000000000002\",\"value\":\"100\"}"
  },
  "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": "permit_inspect_eip2612",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "850bd8c2e3e64d68f6ce07c45a0408df0825974d4a549b7779544bc92890e082",
   "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-eip-2612-permit-inspector-d47af750/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)