# Perp holders · API reference · Femtos

> Largest open positions of a perp, long and short. GET /v1/holders on HyperCore: parameters, response fields and a live call per layer.

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  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/holders-positions

## Perp holders — GET `/v1/holders`

Largest open positions of a perp, long and short.

Layers: HyperCore. Not on Elysium or HyperEVM: kind=positions: open positions of a HyperCore perp; an EVM token has balances only (the holders page).
Page with live calls: https://femtos.xyz/reference/holders-positions?layer=hypercore

| Param | In | Example or values | Meaning |
|---|---|---|---|
| `layer` | query | `(empty)`, `hypercore`, `hyperevm`, `elysium` | Layer |
| `token` | query | `BTC` | Token address (Elysium, HyperEVM), token name or perp coin (HyperCore) |
| `kind` | query | `positions`, `balances` | HyperCore: spot balances of a token, or perp positions (open interest by account) of a coin (spot / perp: the same). Default: positions for a perp coin, else balances |
| `limit` | query | `20` | Rows |

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/holders?layer=hypercore&token=BTC&kind=positions&limit=20"
```

| Field | Type | Meaning |
|---|---|---|
| `holders[]` | object | {address, amount, share, side, usd, label, system, entity} |
| `totalHolders` | int | Holders (system excluded by default) |
| `top10Share` | number \| null | Sum of the top-10 shares |
| `system[]` | object | System addresses (≤ 50), share of supply including them: {address, amount, share, side, usd, label, system, entity} |
| `asOf` | ms | Snapshot time |
| `height` | int | Block of the snapshot (HyperCore: snapshot height; EVM: the indexed head the balances include) |

## Related (Holders & tokens)

- [Token registry](https://femtos.xyz/reference/coins.md) `GET /v1/coins`: HyperCore tokens with their HyperEVM contract and price. (Elysium, HyperCore, HyperEVM)
- [Coin detail](https://femtos.xyz/reference/coin.md) `GET /v1/coins/{layer}/{id}`: One token: its links across layers, the markets it trades on, its 5 largest holders. (Elysium, HyperCore, HyperEVM)
- [Token metadata](https://femtos.xyz/reference/tokens-batch.md) `GET /v1/tokens`: Metadata of up to 100 tokens: supply, creator, logo and socials when indexed, family, spam. Also POST with a JSON body. (Elysium, HyperCore, HyperEVM)
- [Token overview](https://femtos.xyz/reference/token-overview.md) `GET /v1/tokens/{address}`: One token across all its pools: price, FDV, market cap, liquidity, windows, holders, top pools. (Elysium, HyperEVM)
- [Token across layers](https://femtos.xyz/reference/token-lifecycle.md) `GET /v1/tokens/{address}/lifecycle`: One token from its Elysium launch to its HyperEVM mirror, HyperCore spot and perps, each link proven or marked inferred. (Elysium, HyperCore, HyperEVM)
- [Holders](https://femtos.xyz/reference/holders.md) `GET /v1/holders`: Spot balances of a HyperCore token, largest first. (Elysium, HyperCore, HyperEVM)
- [Token families](https://femtos.xyz/reference/token-families.md) `GET /v1/token-families`: Tokens whose balance moves without Transfer logs: Aave aTokens and debt tokens, stHYPE, xStocks. (Elysium, HyperEVM)
- [Family token holders](https://femtos.xyz/reference/token-family.md) `GET /v1/token-families/{token}`: Holders of one family token with balanceOf at the indexed head. (Elysium, HyperEVM)
- [Token transfers](https://femtos.xyz/reference/transfers.md) `GET /v1/transfers`: ERC-20 Transfer events of one token, newest first. (Elysium, HyperEVM)
- [Token security](https://femtos.xyz/reference/token-security.md) `GET /v1/tokens/{address}/security`: Honeypot check: a buy, a transfer and a sell simulated on our node, taxes, owner powers, holders and LP, with a verdict. (Elysium, HyperEVM)
- [Spam tokens](https://femtos.xyz/reference/spam-tokens.md) `GET /v1/tokens/spam`: Tokens the indexer flags as spam, left out of every list, and the latest flag changes. (Elysium, HyperEVM)

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