# x402-defi-intel Token Approval Check

> x402-defi-intel Token Approval Check is a paid API for AI agents from cryptodefidataintel-production.up.railway.app, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Checks ERC-20 token approval allowances for a wallet address on a given chain, flagging unlimited or risky approvals

## Facts

- Endpoint: GET https://cryptodefidataintel-production.up.railway.app/api/approval-check
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-defi-intel-token-approval-check-e97e2eab
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__ym18BCKBQ146ZM1-fGaf

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 x402-defi-intel-token-approval-check-e97e2eab
```

Example prompt: Can you check all the token approval allowances for my wallet 0xAbC...123 on Ethereum for the USDC token at 0xA0b86991...? I want to know if any spenders have unlimited approval that I should revoke.

## When to prefer this

Use this endpoint when an agent needs to audit or surface ERC-20 token spending permissions for a specific wallet on a given chain, especially to identify unlimited or potentially dangerous approvals that should be revoked. Prefer this over generic blockchain explorers when you need a structured, agent-friendly response with named spenders and risk signals.

## Known failure modes

- Invalid or malformed wallet address returns error or empty approvals
- Unsupported chain identifier causes a 400 or no-data response
- Invalid token contract address returns empty results
- RPC node unavailability causes timeout or 503 error
- No approvals found returns empty approvals array with no signal

## How this service works

Crypto-agent toolkit: cross-chain DeFi intelligence + execution helpers + retrieval for agents. 16 endpoints: funding, open interest, long/short, token-safety, yield, prices, gas, tx-simulate, approval-check, bridge-quote, governance-search, lending, liquidations, protocol-search, swap-quote, token-resolve. Pay-per-call via x402.

## Output

Returns a list of approvals for the specified token and wallet, including spender addresses, spender names (e.g. Permit2/Uniswap), whether each approval is unlimited, a risk signal (e.g. 'unlimited_approval_present'), a plain-English insight, data sources, and a confidence score.

## 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"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "chain",
      "owner",
      "token"
     ],
     "properties": {
      "chain": {
       "type": "string"
      },
      "owner": {
       "type": "string"
      },
      "token": {
       "type": "string"
      },
      "spender": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "chain": "ethereum",
   "approvals": [
    {
     "spender": "0x0000...A78BA3",
     "unlimited": true,
     "spenderName": "Permit2 (Uniswap)"
    }
   ]
  },
  "signal": "unlimited_approval_present",
  "insight": "1 UNLIMITED approval present — consider revoking.",
  "sources": [
   "public-rpc"
  ],
  "confidence": 0.85
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-defi-intel-token-approval-check-e97e2eab/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from cryptodefidataintel-production.up.railway.app](https://www.zero.xyz/host/cryptodefidataintel-production.up.railway.app/llms.txt)