# Vextorium Contract Events

> Vextorium Contract Events is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-11).

Fetches and decodes the latest events emitted by an EVM smart contract given a full event signature, returning parameter values, block numbers, and transaction hashes over a specified block range.

## Facts

- Endpoint: POST https://api.vextorium.com/v1/contract-events?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/vextorium-contract-events-cc52b62a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cwPov_b4_Vvw3pOGJKb4k

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 vextorium-contract-events-cc52b62a -d '<json body>'
```

Example prompt: Can you pull the last 100 Transfer(address indexed from, address indexed to, uint256 value) events from contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base, looking back over the last 2000 blocks, and show me the decoded addresses and amounts?

## When to prefer this

Choose this endpoint when you need decoded, human-readable event logs from a specific EVM smart contract across Base, Ethereum, Arbitrum, Optimism, or Polygon — especially when you have the full event signature with parameter names and need values decoded by name rather than raw hex. It's ideal for monitoring recent on-chain activity, auditing contract events, or extracting structured data from event logs without running your own node. Prefer it over generic block explorers when you need programmatic, structured JSON output ready for agent consumption.

## Known failure modes

- Invalid or malformed event signature returns an error or empty results
- Contract address not found on the specified network returns zero events
- Block range exceeds the 5000-block maximum, causing a validation error
- Network enum value not supported returns a schema validation error
- Non-indexed dynamic parameters (string/bytes) are returned as raw 32-byte words rather than decoded strings
- Requesting more than 200 events returns a validation error
- Payment not attached or insufficient USDC causes an x402 payment required error

## How this service works

Latest events emitted by an EVM contract from the event signature (e.g. Transfer(address indexed from,address indexed to,uint256 value)), decoded with parameter names, block and transaction hash, over the last N blocks.

## Output

Returns a JSON object containing the canonical event signature, the keccak256 topic0 hash, the network and contract queried, total events found, number of blocks reviewed, and an array of decoded event objects — each with the transaction hash, block number, and a values map of named parameters (e.g. 'from', 'to', 'value') extracted from the event log data.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "event": {
   "type": "string",
   "description": "Event signature with indexed markers and names"
  },
  "limit": {
   "type": "integer",
   "description": "Events (1-200, default 50)"
  },
  "blocks": {
   "type": "integer",
   "description": "Blocks back (10-5000, default 2000)"
  },
  "network": {
   "enum": [
    "base",
    "ethereum",
    "arbitrum",
    "optimism",
    "polygon"
   ],
   "type": "string"
  },
  "contract": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "note": "Dynamic values (non-indexed string/bytes) are returned as a raw word.",
  "event": "Transfer(address,address,uint256)",
  "found": 1957,
  "events": [
   {
    "hash": "0x359530c6c0662f964433082b08488f565b893a9c54083a6edb12b3e04a8333d5",
    "block": 52083754,
    "values": {
     "to": "0x41D4934322f2bd6fE1dbe4124070FE61651A2067",
     "from": "0x61040E143A77F165Ba44543AF4A079F2C809D14b",
     "value": "83126144588"
    }
   },
   {
    "hash": "0x48d57ad6140d5c2a949f7ce0dcdfff54cc13f75010a762428c9080f0ac26e5fe",
    "block": 52083754,
    "values": {
     "to": "0xb2cc224c1c9feE385f8ad6a55b4d94E92359DC59",
     "from": "0x787fD1dc3b533171781e4Ae1A563c1AC7b4435E4",
     "value": "149022949510"
    }
   }
  ],
  "topic0": "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
  "network": "base",
  "contract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "reviewed_blocks": 20
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/vextorium-contract-events-cc52b62a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)