# Base Contract Control Event Feed

> Base Contract Control Event Feed is a paid API for AI agents from xx402.icu, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Returns recent contract control events (ownership transfers, upgrades, pauses, role changes) on the Base blockchain within a configurable block window

## Facts

- Endpoint: GET https://xx402.icu/x402/api/base-contract-control-event-feed
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-contract-control-event-feed-3afb2191
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_sBfLhMiXstihDYyxX6Lup

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 base-contract-control-event-feed-3afb2191
```

Example prompt: Scan the last 2000 blocks on Base for ownership, upgrade, and pause events — show me up to 30 control events, flagging anything that looks high risk across all contracts chain-wide.

## When to prefer this

Use this endpoint when you need to detect smart contract administrative control changes (ownership, upgrades, pauses, role changes) on the Base blockchain in near-real-time. Prefer this over generic block explorers when you need pre-ranked risk queues, watchlists, and avoid lists rather than raw event logs. Best for DeFi risk monitoring agents, audit tools, and automated security workflows focused on Base.

## Known failure modes

- Invalid contract_address format returns an error or empty results
- window_blocks outside the 100–5000 range is rejected
- limit outside 3–50 range is rejected
- Payment not included or insufficient USDC causes 402 response
- No events found in the requested window returns empty queues
- Unsupported event_type value may return empty or partial results

## How this service works

Paid x402 buyer market scout, x402 paid resource preflight, x402 seller visibility audit, Base actionable risk feed, liquidity exit risk alerts, pool launch risk feed, stable asset risk feed, contract control event feed, protocol outflow risk feed, yield pool allocation risk feed, protocol fee quality feed, token watchlist decision packet, wallet watchlist decision packet, approval risk feed, ranked DeFi review queues with incident history, onchain risk decision packet, promoted token campaign decision packet, large transfer decision packet, token candidate screening decision radar, DEX pair anomaly decision radar, wallet safety decision packet, counterparty flow, allowance, approval exposure, DEX pair routing risk, token trade safety, token liquidity, token flow, holder concentration, contract controls, batch token screening decision packets, token diligence, and BTC15 prediction-market microstructure, execution-friction, calibration-slice, recent market tape, resolved feature sample, and threshold-pressure packets for agents and risk tools.

## Output

A JSON object containing a summary of detected control events, a ranked control_event_queue of recent events with metadata, a review_queue and avoid_queue of flagged contracts, a watchlist, and source_status/sources fields indicating data feed health.

## Response schema (JSON Schema)

```json
{
 "keys": [
  "summary",
  "contract_control_decision",
  "priority_queue",
  "risk_breakdown",
  "control_event_queue",
  "review_queue",
  "avoid_queue",
  "watchlist",
  "bucket_counts",
  "source_status",
  "sources"
 ],
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-contract-control-event-feed-3afb2191/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from xx402.icu](https://www.zero.xyz/host/xx402.icu/llms.txt)