# Token families · API reference · Femtos

> Tokens whose balance moves without Transfer logs: Aave aTokens and debt tokens, stHYPE, xStocks. GET /v1/token-families on Elysium and HyperEVM: parameters, response fields and a live call per layer.

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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/token-families

## Token families — GET `/v1/token-families`

Tokens whose balance moves without Transfer logs: Aave aTokens and debt tokens, stHYPE, xStocks.

Layers: Elysium, HyperEVM. Not on HyperCore: HyperCore balances are ledger entries, never moved without a record: the holders page counts them.
Page with live calls: https://femtos.xyz/reference/token-families?layer=<elysium|hyperevm>

| Param | In | Example or values | Meaning |
|---|---|---|---|
| `layer` | query | `elysium` (Elysium); `hyperevm` (HyperEVM) | EVM layer |
| `family` | query | `(empty)`, `aave_atoken`, `aave_vtoken`, `sthype`, `wrapped_shares`, `backed`, `scaling_factor` | One family: aave_atoken, aave_vtoken, sthype, wrapped_shares, backed, scaling_factor |
| `includeSpam` | query | `(empty)`, `true` | Show spam tokens (tokens.spam: homoglyph, impostor, phishing name, fake transfers…) flagged spam / spamReason; left out of the list by default |

Elysium:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/token-families?layer=elysium"
```

HyperEVM:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/token-families?layer=hyperevm"
```

| Field | Type | Meaning |
|---|---|---|
| `families.<key>` | object | Tokens per family |
| `tokens[]` | object | {token, family, description, symbol, name, decimals, params, firstSeenBlock, spam, spamReason} |
| `tokens[].description` | string \| null | How balanceOf follows from the base |

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