# presign-guard ERC-20 Allowance Audit

> presign-guard ERC-20 Allowance Audit is a paid API for AI agents from presign-guard.onrender.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-11).

Audits all open ERC-20 token approvals for an EVM wallet, flagging risky or unlimited allowances with a green/orange/red verdict, grade, and revocation recommendations.

## Facts

- Endpoint: GET https://presign-guard.onrender.com/v1/approvals?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/presign-guard-erc-20-allowance-audit-2c90b722
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_feog-UtfknoucQ3_eSI9b

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 presign-guard-erc-20-allowance-audit-2c90b722
```

Example prompt: Can you audit all the open ERC-20 token approvals on my Ethereum wallet 0xAbc123...def and tell me which ones are risky or unlimited and which I should revoke?

## When to prefer this

Choose this endpoint when you need a comprehensive, pre-interpreted audit of all ERC-20 token approvals for a specific EVM wallet — especially when you want spender identity resolution, risk grading, and actionable revocation recommendations in a single call. It is preferable over raw on-chain queries when you want human-readable severity labels and aggregated risk verdicts rather than raw event logs.

## Known failure modes

- Invalid or malformed wallet address returns an error — ensure 0x-prefixed checksummed address
- Unsupported chain value returns error — only base, ethereum, arbitrum, optimism, polygon, bsc are valid
- Wallet with no approvals returns empty approvals array with green verdict
- Rate limiting or upstream RPC failures may cause timeouts or 5xx responses
- Very new wallets or chains with limited indexer coverage may show incomplete approval history

## How this service works

Wallet approval audit (green/orange/red, grade, one-line summary): every open ERC-20 allowance of an EVM wallet with who the spender is (flagged, plain wallet, unverified, unlimited) and which ones to revoke

## Output

Returns a JSON object with: a top-level verdict (green/orange/red), a grade label (SAFE/CAUTION/RISKY/AVOID), a one-liner plain-language summary, an array of all open approvals (each with token, spender address, spender name if known, trust status, allowance amount, approval timestamp, severity, reason codes, and a revoke flag), an array of reason objects with severity codes, a summary object with counts (approvals, tokens, unlimited, toRevoke), a timestamp, and a revoke URL for easy remediation.

## 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",
      "address"
     ],
     "properties": {
      "chain": {
       "enum": [
        "base",
        "ethereum",
        "arbitrum",
        "optimism",
        "polygon",
        "bsc"
       ],
       "type": "string",
       "description": "EVM chain to audit"
      },
      "address": {
       "type": "string",
       "description": "Wallet address (0x...)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "verdict",
      "grade",
      "one_liner",
      "reasons",
      "approvals"
     ],
     "properties": {
      "grade": {
       "enum": [
        "SAFE",
        "CAUTION",
        "RISKY",
        "AVOID"
       ],
       "type": "string"
      },
      "reasons": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "code",
         "severity"
        ],
        "properties": {
         "code": {
          "type": "string"
         },
         "details": {},
         "severity": {
          "enum": [
           "red",
           "orange",
           "info"
          ],
          "type": "string"
         }
        }
       }
      },
      "receipt": {
       "type": "object",
       "required": [
        "request_id",
        "route",
        "input_sha256",
        "signed_at",
        "signer",
        "algorithm",
        "signature"
       ],
       "properties": {
        "cert": {
         "type": "object",
         "properties": {
          "signer": {
           "type": "string"
          },
          "service": {
           "type": "string"
          },
          "authority": {
           "type": "string"
          },
          "signature": {
           "type": "string"
          },
          "valid_from": {
           "type": "string"
          }
         },
         "description": "The payout wallet's certificate for this signing key:
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/presign-guard-erc-20-allowance-audit-2c90b722/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from presign-guard.onrender.com](https://www.zero.xyz/host/presign-guard.onrender.com/llms.txt)