# Liquidity events · API reference · Femtos

> Liquidity added to and removed from one pool, newest first. GET /v1/liquidity on Elysium 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`
- Auth: `Authorization: Bearer $FEMTOS_KEY`. Free key: https://femtos.xyz/account/new (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/reference/liquidity

## Liquidity events — GET `/v1/liquidity`

Liquidity added to and removed from one pool, newest first.

Layers: Elysium, HyperEVM. Not on HyperCore: HyperCore trades on its order book, not on pools: its markets, trades and candles are on the same pages.
Page with live calls: https://femtos.xyz/reference/liquidity?layer=<elysium|hyperevm>

| Param | In | Example or values | Meaning |
|---|---|---|---|
| `layer` | query | `elysium` (Elysium); `hyperevm` (HyperEVM) | EVM layer |
| `pair` | query | `0xc6f0177141b2741171519c0ef76ad62e5602968b` (Elysium); `0x6c9a33e3b592c0d65b3ba59355d5be0d38259285` (HyperEVM) | Pool address or <PoolManager>:<PoolId> |
| `limit` | query | `20` | Rows |
| `cursor` | query | (optional) | Next page: `next_cursor` of the previous answer |

Elysium:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/liquidity?layer=elysium&pair=0xc6f0177141b2741171519c0ef76ad62e5602968b&limit=20"
```

HyperEVM:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/liquidity?layer=hyperevm&pair=0x6c9a33e3b592c0d65b3ba59355d5be0d38259285&limit=20"
```

| Field | Type | Meaning |
|---|---|---|
| `rows[]` | object | Newest first: {block, t, tx, logIndex, kind, provider, amount0, amount1, usd, liquidityDelta, tickLower, tickUpper} |
| `rows[].liquidityDelta` | string \| null | V4 ModifyLiquidity liquidity delta |
| `token0` | object | {address, symbol, decimals, spam, spamReason} |
| `token1` | object | {address, symbol, decimals, spam, spamReason} |
| `next_cursor` | string \| null | Opaque cursor of the next page: pass it as `cursor`, unchanged. null on the last page |

Next page: `cursor` = the `next_cursor` of the previous answer (https://femtos.xyz/agents.md#pagination).

## 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)
- [Forming candle](https://femtos.xyz/reference/ws/candles.md) `WS elysium.candles · hc.candles · hyperevm.candles`: The forming candle, pushed once per block where it changes. (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)
- [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