# Coin detail · API reference · Femtos

> One token: its links across layers, the markets it trades on, its 5 largest holders. GET /v1/coins/{layer}/{id} on Elysium, HyperCore and HyperEVM: 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/coin

## Coin detail — GET `/v1/coins/{layer}/{id}`

One token: its links across layers, the markets it trades on, its 5 largest holders.

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

| Param | In | Example or values | Meaning |
|---|---|---|---|
| `layer` | path | `elysium` (Elysium); `hypercore` (HyperCore); `hyperevm` (HyperEVM) | Layer |
| `id` | path | `<token>` (Elysium); `HYPE` (HyperCore); `<evmToken>` (HyperEVM) | HyperCore token name (HYPE) or 0x address (HyperEVM, Elysium) |
| `includeSpam` | query | `(empty)`, `true` | Pools of spam tokens in `markets` (a spam coin always lists its own pools) (Elysium, HyperEVM) |

Elysium:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/coins/elysium/<token>"
```

HyperCore:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/coins/hypercore/HYPE"
```

HyperEVM:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/coins/hyperevm/<evmToken>"
```

| Field | Type | Meaning |
|---|---|---|
| `coin` | object | /api/coins item; a spam token still answers, flagged spam / spamReason: {layer, id, symbol, name, decimals, totalSupply, priceUsd, links, coverage, spam, spamReason} |
| `markets[]` | object | Markets where it is base or quote, most traded first: {layer, id, symbol, base, quote, kind, price, priceUsd, change24h, volume24hUsd, trades24h, szDecimals, …} |
| `holders` | object | Holders (5 largest) or {unavailable} |

## 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)
- [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)
- [Perp holders](https://femtos.xyz/reference/holders-positions.md) `GET /v1/holders`: Largest open positions of a perp, long and short. (HyperCore)
- [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)
- [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