# xx402 ERC20 Token Allowance Risk Checker (Base Chain)

> xx402 ERC20 Token Allowance Risk Checker (Base Chain) is a paid API for AI agents from x402.xx402.icu, paid per call via x402, $0.001/call, status down (last checked 2026-10-24).

Fetches and risk-assesses the ERC20 token allowance granted by an owner to a spender on the Base blockchain, including exposure analysis and revocation guidance.

## Facts

- Endpoint: GET https://x402.xx402.icu/api/base-chain/allowance?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/xx402-erc20-token-allowance-risk-checker-base-chain-78203f24
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lAISZjSlOy9etip2NqPFy

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 xx402-erc20-token-allowance-risk-checker-base-chain-78203f24
```

Example prompt: Check the USDC allowance on Base that wallet 0xba76c7ECa175f67cFcE475c09498f840176bf497 has approved for spender 0xba76c7ECa175f67cFcE475c09498f840176bf497 — give me the risk summary and tell me if I should revoke it.

## When to prefer this

Use this endpoint when you need a structured, risk-annotated view of a specific ERC20 token allowance on the Base chain, especially when you want both the raw allowance figure and actionable risk guidance (decision, exposure level, revocation call) in a single response. Prefer it over raw on-chain RPC calls when you need the risk intelligence layer on top of chain data, and over generic block explorers when you need machine-readable output suitable for autonomous agent decision-making.

## Known failure modes

- Invalid wallet address format returns a 400 or schema validation error
- Unknown or unverified token contract may return incomplete source_status
- On-chain RPC unavailability causes source_status failures with partial data
- Payment not completed (x402) returns 402 Payment Required before data is served
- Very new token contracts may have no risk data, resulting in sparse risk_breakdown

## How this service works

Paid Base token, wallet, DeFi, chain-read, x402 buyer/seller discovery, and specialized Bitcoin 15-minute Up/Down prediction-market data packets for autonomous agents and risk tools.

## Output

Returns a JSON object with a plain-language risk summary, a risk decision label, the current allowance amount, token metadata, owner and spender addresses, an exposure level assessment, an unsigned revoke transaction call (if applicable), a risk breakdown by category, prioritized next-product recommendations, and source status indicating which on-chain or off-chain data sources were used.

## Response schema (JSON Schema)

```json
{
 "keys": [
  "summary",
  "decision",
  "allowance",
  "token",
  "owner",
  "spender",
  "exposure",
  "unsigned_revoke_call",
  "next_products",
  "priority_queue",
  "risk_breakdown",
  "review_queue",
  "avoid_queue",
  "bucket_counts",
  "source_status",
  "sources"
 ],
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/xx402-erc20-token-allowance-risk-checker-base-chain-78203f24/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.xx402.icu](https://www.zero.xyz/host/x402.xx402.icu/llms.txt)