# SperaxOS Contract Events Explorer

> SperaxOS Contract Events Explorer is a paid API for AI agents from chat.sperax.io, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-16).

Fetches on-chain smart contract events from EVM-compatible blockchains, optionally filtered by event signature, returning recent decoded event data.

## Facts

- Endpoint: POST https://chat.sperax.io/api/x402/tools/contract-explorer/getContractEvents?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/speraxos-contract-events-explorer-56b9c2e1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_myAQDEoxdPmJBimsZOdns

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 speraxos-contract-events-explorer-56b9c2e1 -d '<json body>'
```

Example prompt: Can you pull the last 20 Transfer events from the USDC contract at 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on Ethereum?

## When to prefer this

Choose this endpoint when you need to retrieve historical or recent on-chain event logs for a specific EVM smart contract across multiple chains (Ethereum, Arbitrum, Polygon, Base, Optimism, Avalanche, BSC) without needing a traditional API key. It is ideal for DeFi intelligence workflows where pay-per-use micro-payments via USDC on Base are acceptable and you want decoded event data with optional event signature filtering.

## Known failure modes

- Invalid or malformed contract address returns an error
- Unsupported chain name results in a bad request response
- No events found for the specified filter returns an empty array
- Payment failure via x402 (insufficient USDC balance) blocks the request
- Rate limiting or RPC node unavailability may cause timeouts
- Very new contracts with no event history return empty results

## How this service works

AI-powered DeFi intelligence APIs payable via the x402 HTTP payment protocol. No API key required — pay per request with USDC on Base. Identity-only (SIWX) endpoints are free for wallets with an agentcash identity.

## Output

Returns a list of decoded on-chain event log entries for the specified contract, each containing event name, topics, decoded parameters, block number, transaction hash, and timestamp. Filtered by the provided event signature if supplied, limited to the requested count.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "type": "string",
   "description": "Chain name: ethereum, arbitrum, polygon, base, optimism, avalanche, bsc. Defaults to ethereum."
  },
  "limit": {
   "type": "number",
   "description": "Max number of events to return (default 10)"
  },
  "address": {
   "type": "string",
   "description": "EVM contract address (0x…)"
  },
  "eventSignature": {
   "type": "string",
   "description": "Optional: filter by event signature topic (e.g. \"Transfer(address,address,uint256)\")"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/speraxos-contract-events-explorer-56b9c2e1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chat.sperax.io](https://www.zero.xyz/host/chat.sperax.io/llms.txt)