# Forming candle · API reference · Femtos

> The forming candle, pushed once per block where it changes. WebSocket channels elysium.candles · hc.candles · hyperevm.candles on Elysium, HyperCore and HyperEVM: parameters, response fields and a live call per layer.

- Base URL: `https://api.femtos.xyz/v1` (REST) · `wss://api.femtos.xyz/v1/ws` (WebSocket) · MCP: `https://api.femtos.xyz/mcp`
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- 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/reference/ws/candles

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

## Forming candle — WS `elysium.candles · hc.candles · hyperevm.candles`

The forming candle, pushed once per block where it changes.

Layers: Elysium, HyperCore, HyperEVM.
Page with live calls: https://femtos.xyz/reference/ws/candles?layer=<elysium|hypercore|hyperevm>

| Param | In | Example or values | Meaning |
|---|---|---|---|
| `pair` | filter | `<pair>` (Elysium); `<evmPair>` (HyperEVM) | Pool key: the pool address, or <PoolManager>:<PoolId> (V4, PancakeSwap Infinity); any case (Elysium, HyperEVM) |
| `tf` | filter | `1s`, `15s`, `1m`, `5m`, `15m`, `1h`, `4h`, `1d` | Candle unit |
| `coin` | filter | `BTC` | HyperCore market: BTC, @107 (spot), xyz:TSLA (HIP-3) (HyperCore) |

Elysium:

```json
{"op":"subscribe","channel":"elysium.candles","filter":{"pair":"<pair>","tf":"1m"}}
```

HyperCore:

```json
{"op":"subscribe","channel":"hc.candles","filter":{"coin":"BTC","tf":"1s"}}
```

HyperEVM:

```json
{"op":"subscribe","channel":"hyperevm.candles","filter":{"pair":"<evmPair>","tf":"1m"}}
```

| Field | Type | Meaning |
|---|---|---|
| `snapshot: true` | Candle[] | last 300 candles at subscribe (Elysium, HyperEVM) |
| `data` | WsCandle | the forming candle, once per block where it changes: {t, o, h, l, c, v, vq, n, vUsd, mcUsd, usd, mcap, …} (Elysium, HyperCore) |
| `snapshot: true` | WsCandle[] | last 300 candles at subscribe (HyperCore) |
| `data` | WsCandle | the forming candle: each candle that changed (while syncing: up to 50 per poll): {t, o, h, l, c, v, vq, n, vUsd, mcUsd, usd, mcap, …} (HyperEVM) |

## Related (Market data)

- [Markets](https://femtos.xyz/reference/markets.md) `GET /v1/markets`: Every tradable perp, spot, HIP-3 and outcome market with 24 h stats. (Elysium, HyperCore, HyperEVM)
- [Candles](https://femtos.xyz/reference/candles.md) `GET /v1/candles`: OHLCV of any HyperCore market down to 1 s, ascending, UTC-aligned. (Elysium, HyperCore, HyperEVM)
- [Token candles](https://femtos.xyz/reference/token-candles.md) `GET /v1/candles`: OHLCV of a token through its USDC market (a perp coin: the perp). (Elysium, HyperCore, HyperEVM)
- [Trades](https://femtos.xyz/reference/trades.md) `GET /v1/trades`: Latest fills of one market, newest first. (Elysium, HyperCore, HyperEVM)
- [Trades stream](https://femtos.xyz/reference/ws/trades.md) `WS elysium.trades · hc.trades · hyperevm.trades`: All trades of one market as they happen: raced between our node and Hyperliquid's public feed, first copy sent, the other dropped. (Elysium, HyperCore, HyperEVM)
- [Order book](https://femtos.xyz/reference/book.md) `GET /v1/book`: L2 book of one market with order counts, from our node. (HyperCore)
- [Book stream](https://femtos.xyz/reference/ws/book.md) `WS hc.book`: Full-depth book, then the levels each block changes. (HyperCore)
- [Best bid / offer](https://femtos.xyz/reference/ws/bbo.md) `WS hc.bbo`: Top of book of one market each block: raced between Hyperliquid's public feed and our node (newest block wins, our node corrects the same block). (HyperCore)
- [Order updates](https://femtos.xyz/reference/ws/orders.md) `WS hc.orders`: Every order status change, filterable by coin, user and status. (HyperCore)
- [Token prices](https://femtos.xyz/reference/prices.md) `GET /v1/prices`: USD price of up to 100 tokens in one call, each with its source and provenance. (Elysium, HyperCore, HyperEVM)
- [Price history](https://femtos.xyz/reference/price-history.md) `GET /v1/prices/history`: USD closes per unit of up to 25 tokens over a window, or the price of 100 tokens at one time (at=). (Elysium, HyperCore, HyperEVM)
- [HYPE price](https://femtos.xyz/reference/ws/prices.md) `WS prices.hype`: HYPE from the Hyperliquid oracle, perp mark and exchanges. (HyperCore)
- [Pool detail](https://femtos.xyz/reference/pool.md) `GET /v1/pools/{address}`: One pool: dex, fee, tokens, liquidity in USD, depth, 5m to 24h activity, top LPs. (Elysium, HyperEVM)
- [Liquidity events](https://femtos.xyz/reference/liquidity.md) `GET /v1/liquidity`: Liquidity added to and removed from one pool, newest first. (Elysium, HyperEVM)
- [Daily token volume](https://femtos.xyz/reference/volume.md) `GET /v1/volume`: USD swap volume of a token per UTC day, both sides of every priced swap. (Elysium, HyperEVM)

Every page: https://femtos.xyz/reference.md