# EIP-712 Typed-Data Signature Risk Decoder

> EIP-712 Typed-Data Signature Risk Decoder is a paid API for AI agents from gpt55.558686.xyz, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Inspects EIP-712, Permit, and Permit2 typed-data structures before signing to surface spender, value, deadline, nonce, chainId, and verifyingContract risk fields

## Facts

- Endpoint: POST https://gpt55.558686.xyz/v1/paid/eip712-signature-risk-decoder
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/eip-712-typed-data-signature-risk-decoder-58981723
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Azsr4maRAvxiyQecxpse1

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 eip-712-typed-data-signature-risk-decoder-58981723 -d '<json body>'
```

Example prompt: Before I sign this Permit2 message, decode it and tell me who the spender is, how much value they can take, when the deadline expires, and whether there are any red flags — here's the typed data: {typedData}

## When to prefer this

Use this endpoint when an AI agent or wallet needs to programmatically assess the risk of an EIP-712, Permit, or Permit2 signature request before the user approves it — especially when spender identity, token value, deadlines, or chain context need to be surfaced clearly. Prefer this over generic contract decoders when the payload is specifically a typed-data signing request rather than a raw transaction.

## Known failure modes

- Malformed or unparseable typed data returns a parse error
- Missing required typed-data fields yields incomplete risk assessment
- Unrecognized domain or verifyingContract may return unknown risk label
- Payment not included or insufficient USDC results in 402 response
- Invalid chain ID causes chain mismatch warning or error
- Extremely large typed-data payloads may be rejected due to maxLength limits

## Output

Returns a structured risk report including decoded spender address, value at risk, deadline, nonce, chain ID, verifying contract, and any identified risk warnings or anomalies present in the EIP-712 / Permit / Permit2 typed-data payload

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "properties": {
      "json": {
       "type": "string",
       "maxLength": 50000,
       "minLength": 2
      },
      "text": {
       "type": "string",
       "maxLength": 50000,
       "minLength": 2
      },
      "chain": {
       "type": "string",
       "maxLength": 80
      },
      "value": {
       "type": "object",
       "additionalProperties": true
      },
      "typedData": {
       "oneOf": [
        {
         "type": "object",
         "additionalProperties": true
        },
        {
         "type": "string",
         "maxLength": 50000,
         "minLength": 2
        }
       ]
      },
      "typed_data": {
       "oneOf": [
        {
         "type": "object",
         "additionalProperties": true
        },
        {
         "type": "string",
         "maxLength": 50000,
         "minLength": 2
        }
       ]
      },
      "known_addresses": {
       "type": "object",
       "additionalProperties": {
        "type": "string"
       }
      },
      "expected_chain_id": {
       "oneOf": [
        {
         "type": "string"
        },
        {
         "type": "number"
        }
       ]
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "tool": {
       "type": "string"
      },
      "fetchedAt": {
       "type": "string"
      }
     },
     "additionalProperties": true
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/eip-712-typed-data-signature-risk-decoder-58981723/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gpt55.558686.xyz](https://www.zero.xyz/host/gpt55.558686.xyz/llms.txt)