# KOL stream · HyperEVM API · Femtos

> Every HyperEVM swap, transfer and bridge leg of a named wallet, on each indexed block.

- Base URL: `https://api.femtos.xyz/v1` (REST) · `wss://api.femtos.xyz/v1/ws` (WebSocket) · MCP: `https://api.femtos.xyz/mcp`
- Auth: `Authorization: Bearer $FEMTOS_KEY` (or `X-API-KEY: $FEMTOS_KEY`). Free key: https://femtos.xyz/accounts/ (browser), or with
  no browser: `GET https://femtos.xyz/accounts/agent/challenge`, solve its proof of work, then `POST https://femtos.xyz/accounts/agent/signup`
  (https://femtos.xyz/agents.md#agent-onboarding)
- Decimals are exact strings, times Unix milliseconds, addresses lowercase `0x`
- Whole API in one file: https://femtos.xyz/agents.md · OpenAPI: https://api.femtos.xyz/v1/openapi.json · Index: https://femtos.xyz/llms.txt
- Page with live calls: https://femtos.xyz/hyperevm/ws-kols

WebSocket: get a ticket (`POST https://api.femtos.xyz/v1/ws-ticket` with your key), connect to `wss://api.femtos.xyz/v1/ws?ticket=$TICKET`, send the frame below; the first message has `"snapshot": true`. Details: https://femtos.xyz/agents.md#websocket

## KOL stream — WS `kol.activity`

Every HyperEVM swap, transfer and bridge leg of a named wallet, on each indexed block.

| Param | In | Example or values |
|---|---|---|
| `layer` | filter | `hyperevm` |
| `kind` | filter | `(empty)`, `swap`, `transfer`, `bridge` |

```json
{"op":"subscribe","channel":"kol.activity","filter":{"layer":"hyperevm"}}
```

| Field | Type | Meaning |
|---|---|---|
| `snapshot: true` | KolItem[] | last 50 moves seen |
| `data` | KolItem | {layer, kind: swap \| transfer \| bridge, wallet, entity, side, notional} |

## Related (Named wallets)

- [KOL leaderboard](https://femtos.xyz/hyperevm/kols.md): KOLs, traders and funds ranked by their HyperEVM swaps, transfers, bridge legs and holdings.
- [KOL moves](https://femtos.xyz/hyperevm/kol-activity.md): The latest HyperEVM swaps and transfers of the named wallets, with who moved.

All HyperEVM endpoints: https://femtos.xyz/hyperevm.md