# Base ETH Logs

> Base ETH Logs is a paid API for AI agents from ari001.tailb4ac3a.ts.net, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-10).

Fetches Ethereum event logs (eth_getLogs) for a contract address on the Base network, with optional event topic and block range filtering.

## Facts

- Endpoint: GET https://ari001.tailb4ac3a.ts.net/v1/ventures/x402_chain_reads_v1/base_eth_getlogs?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-10
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-eth-logs-70ef7ecb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_X-qYWHfjIUbCRqQsF-O-A

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-eth-logs-70ef7ecb
```

Example prompt: Pull the last 20 blocks of event logs for the Base contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48, filtering to the Transfer event signature 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef.

## When to prefer this

Choose this endpoint when you need raw on-chain event logs from Base L2 contracts and can filter by event signature (topic0). It is ideal for monitoring DeFi activity, auditing ERC-20 transfers, debugging contract events, or building reactive agents that act on on-chain state changes. Prefer this over transaction receipt lookups when you want bulk event scanning across a block range rather than a single transaction's logs.

## Known failure modes

- Invalid contract address format (not 0x + 40 hex) returns validation error
- Invalid topic0 format (not 0x + 64 hex) returns validation error
- blocks value outside 1-100 range rejected
- Contract address has no logs in the requested block range — returns empty array
- RPC node unavailability or Base network issues cause 5xx errors
- Payment of $0.005 USDC not provided or invalid causes 402 payment required

## How this service works

Event logs on Base: takes address (contract, 0x + 40 hex), optional topic0 (event signature hash, 0x + 64 hex) and optional blocks (last N blocks, 1-100, default 10), and returns the matching eth_get…

## Output

Returns an array of matching eth_getLogs entries from Base, each containing the contract address, transaction hash, block number, log index, topics array, and hex-encoded data payload — mirroring the standard Ethereum JSON-RPC eth_getLogs response structure.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "blocks": {
       "type": "string",
       "description": "optional, last N blocks, 1-100 (default 10)"
      },
      "topic0": {
       "type": "string",
       "description": "optional event signature hash, 0x + 64 hex"
      },
      "address": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "contract, 0x + 40 hex"
      }
     }
    }
   },
   "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/base-eth-logs-70ef7ecb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ari001.tailb4ac3a.ts.net](https://www.zero.xyz/host/ari001.tailb4ac3a.ts.net/llms.txt)