API reference · Market data
Book stream
Full-depth book, then the levels each block changes.
- Elysium: not served
- HyperCore
- HyperEVM: not served
- Not on Elysium or HyperEVM: the EVM layers trade on AMM pools, with no order book: pool detail and liquidity events cover a pool
WebSocket channel hc.book on wss://api.femtos.xyz/v1/ws
Parameters
| Param | In | Example or values | Meaning |
|---|---|---|---|
coin | filter | HYPE | HyperCore market: BTC, @107 (spot), xyz:TSLA (HIP-3) |
Subscribe
{"op":"subscribe","channel":"hc.book","filter":{"coin":"HYPE"}}Key: Authorization: Bearer $FEMTOS_KEY. Get a free key, or with no browser through agent onboarding.
Response fields
| Field | Type | Meaning |
|---|---|---|
snapshot: true | HcBook | full depth (a partial top-100 first, `partial: true`, same height) |
data | HcBookDelta | the levels each block changes; sz "0" = level removed: {height, prevHeight, bids, asks} |
data.prevHeight | int | must equal your height, else resubscribe |
Related: Market data
- Markets GET /v1/markets Elysium, HyperCore, HyperEVM
Every tradable perp, spot, HIP-3 and outcome market with 24 h stats. - Candles GET /v1/candles Elysium, HyperCore, HyperEVM
OHLCV of any HyperCore market down to 1 s, ascending, UTC-aligned. - Forming candle WS elysium.candles · hc.candles · hyperevm.candles Elysium, HyperCore, HyperEVM
The forming candle, pushed once per block where it changes. - Token candles GET /v1/candles Elysium, HyperCore, HyperEVM
OHLCV of a token through its USDC market (a perp coin: the perp). - Trades GET /v1/trades Elysium, HyperCore, HyperEVM
Latest fills of one market, newest first. - Trades stream WS elysium.trades · hc.trades · hyperevm.trades Elysium, HyperCore, HyperEVM
All trades of one market as they happen: raced between our node and Hyperliquid's public feed, first copy sent, the other dropped. - Order book GET /v1/book HyperCore
L2 book of one market with order counts, from our node. - Best bid / offer WS hc.bbo HyperCore
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). - Order updates WS hc.orders HyperCore
Every order status change, filterable by coin, user and status. - Token prices GET /v1/prices Elysium, HyperCore, HyperEVM
USD price of up to 100 tokens in one call, each with its source and provenance. - Price history GET /v1/prices/history Elysium, HyperCore, HyperEVM
USD closes per unit of up to 25 tokens over a window, or the price of 100 tokens at one time (at=). - HYPE price WS prices.hype HyperCore
HYPE from the Hyperliquid oracle, perp mark and exchanges. - Pool detail GET /v1/pools/{address} Elysium, HyperEVM
One pool: dex, fee, tokens, liquidity in USD, depth, 5m to 24h activity, top LPs. - Liquidity events GET /v1/liquidity Elysium, HyperEVM
Liquidity added to and removed from one pool, newest first. - Daily token volume GET /v1/volume Elysium, HyperEVM
USD swap volume of a token per UTC day, both sides of every priced swap.
More
- This page as Markdown
- The whole API reference
- What HyperCore serves
- The whole API in one Markdown file
- OpenAPI 3.1 document
Agent guide (agents.md)llms.txtOpenAPIMCP serverGet an API keyChangelog