# xx402 Base ERC20 Approval Risk Feed

> xx402 Base ERC20 Approval Risk Feed is a paid API for AI agents from x402.xx402.icu, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-21).

Scans recent Base blockchain approval logs for ERC20 tokens and returns risk-scored approval data, spender watchlists, and agent decision guidance for autonomous DeFi risk management.

## Facts

- Endpoint: GET https://x402.xx402.icu/api/base-approval-risk-feed?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/xx402-base-erc20-approval-risk-feed-6e4e1e3e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2m0eb9Geu_JCbMuL4vKQ5

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-base-erc20-approval-risk-feed-6e4e1e3e
```

Example prompt: Scan the last 500 blocks on Base for approval risks across USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) and WETH (0x4200000000000000000000000000000000000006), return up to 12 rows, and tell me which spenders I should revoke or watch out for.

## When to prefer this

Choose this endpoint when an autonomous agent or risk tool needs on-chain approval risk data specifically for Base network ERC20 tokens, particularly when building revocation priority lists, spender watchlists, or DeFi risk dashboards that require structured, agent-ready decision outputs rather than raw blockchain data.

## Known failure modes

- Invalid or non-existent token address returns empty results or error
- window_blocks out of range (below 100 or above 3000) returns 400 validation error
- limit out of range (below 3 or above 30) returns validation error
- token_limit exceeding 5 returns validation error
- Payment not completed via x402 protocol returns 402 Payment Required
- Base RPC node unavailable causes scan failure with source_status error flag

## 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 approval risk decisions, a priority queue of high-risk approvals, a review queue, an avoid queue, a revocation priority queue, a spender watchlist, per-token summaries, bucket counts, risk breakdowns, buyer next action guidance, and source status metadata — all structured for autonomous agent consumption.

## Response schema (JSON Schema)

```json
{
 "keys": [
  "summary",
  "purchase_acceptance",
  "buyer_next_action",
  "next_paid_call",
  "decision_evidence",
  "repeat_purchase_guard",
  "approval_risk_decision",
  "priority_queue",
  "best_next_products",
  "risk_breakdown",
  "review_queue",
  "avoid_queue",
  "approval_risk_queue",
  "revocation_priority_queue",
  "spender_watchlist",
  "token_summaries",
  "bucket_counts",
  "source_status",
  "not_financial_advice",
  "sources"
 ],
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/xx402-base-erc20-approval-risk-feed-6e4e1e3e/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)