# Contract Event Logs

> Contract Event Logs is a paid API for AI agents from bess-x402.onrender.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-30).

Fetches raw event logs emitted by an EVM smart contract over a block range, filtered by event signature or topic hash

## Facts

- Endpoint: GET https://bess-x402.onrender.com/v1/evm/events?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/contract-event-logs-3fc41cd1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8XsoEdZHSvvdR7j0sjv8W

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 contract-event-logs-3fc41cd1
```

Example prompt: Can you pull all Transfer events emitted by the USDC contract at 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on Ethereum over the last 500 blocks, up to 200 results?

## When to prefer this

Choose this endpoint when you need raw event logs from a specific smart contract on Ethereum, Base, Arbitrum, Optimism, or Polygon, especially when filtering by a known event signature like Transfer, Swap, or Mint. It is ideal for monitoring DeFi protocol activity, tracking token transfers, auditing governance events, or triggering agent workflows based on on-chain state changes. Prefer it over full-node RPC calls when you want a simple REST interface without managing Web3 infrastructure.

## Known failure modes

- Block range exceeds 5,000 blocks — returns error indicating range limit
- Invalid or non-checksummed contract address — returns bad request error
- Unsupported chain name — returns error with supported chain list
- No logs found in range — returns empty results array
- Invalid event signature format — returns filter error
- Rate limit or payment failure — returns 402 payment required

## How this service works

Event logs a contract emitted (eth_getLogs), filtered by event signature such as Transfer(address,address,uint256) or a topic hash, over a block range (max 5,000 blocks, default last 100). Use to monitor swaps, mints or governance.

## Output

Returns a list of raw event log objects emitted by the specified contract, each including transaction hash, block number, log index, topics array (with the event signature hash and indexed parameters), and the raw data field for non-indexed parameters. Results are bounded by the requested block range (max 5,000 blocks) and limit (1–500).

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "chain": {
       "type": "string",
       "description": "ethereum, base, arbitrum, optimism or polygon"
      },
      "event": {
       "type": "string",
       "description": "Event signature or topic hash"
      },
      "limit": {
       "type": "integer",
       "description": "Maximum number of results (1-500)"
      },
      "address": {
       "type": "string",
       "description": "Contract address"
      },
      "to_block": {
       "type": "string",
       "description": "End block (default latest)"
      },
      "from_block": {
       "type": "string",
       "description": "Start block"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/contract-event-logs-3fc41cd1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bess-x402.onrender.com](https://www.zero.xyz/host/bess-x402.onrender.com/llms.txt)