API reference, Chain & reference

Chain activity stream

• Elysium: The GET /v1/activity answer of Elysium for one interval (its last 120 / 96 / 168 / 90 buckets of 1m / 15m / 1h / 1d), pushed on subscribe, then at each indexed block that moves its open buckets (whole, or as a JSON Patch of the rows that changed).
• HyperEVM: The GET /v1/activity answer of HyperEVM for one interval (its last 120 / 96 / 168 / 90 buckets of 1m / 15m / 1h / 1d), pushed on subscribe, then at each indexed block that moves its open buckets (whole, or as a JSON Patch of the rows that changed).

• Elysium
• HyperCore: not served
• HyperEVM

• Not on HyperCore: HyperCore has no EVM transactions: its trading activity is GET /v1/volume and the markets' 24 h stats (hc.markets)

WebSocket channel elysium.activity on wss://api.femtos.xyz/v1/ws | WebSocket channel hyperevm.activity on wss://api.femtos.xyz/v1/ws

Parameters

Subscribe

Elysium

{"op":"subscribe","channel":"elysium.activity","filter":{"interval":"15m"}}

HyperEVM

{"op":"subscribe","channel":"hyperevm.activity","filter":{"interval":"15m"}}

Key: Authorization: Bearer $FEMTOS_KEY. Get a free key, or with no browser through agent onboarding.

Response fields

Related: Chain & reference

• Freshness GET /v1/status Elysium, HyperCore, HyperEVM
  Head and lag of each layer, measured now.
• Freshness stream WS status Elysium, HyperCore, HyperEVM
  The GET /v1/status answer (head and lag of each layer, live feeds), pushed whole on subscribe and at most once a second when it changes.
• Blocks stream WS elysium.blocks | hyperevm.blocks Elysium, HyperEVM
  Each new HyperEVM block header, small and big blocks, from our node.
• Gas tracker GET /v1/gas Elysium, HyperEVM
  Every HyperEVM block's base fee, gas used and tips over 1h to 7d, with stats and the latest block.
• Gas stream WS elysium.gas | hyperevm.gas Elysium, HyperEVM
  Each new HyperEVM block's base fee, gas used and tips, from our node; the history is GET /v1/gas.
• Chain activity GET /v1/activity Elysium, HyperEVM
  HyperEVM activity per bucket: transactions, wallets and new wallets, contracts, fees, swaps, traders, volume, launches, tokens created and deposits bridged in.
• Chain transactions GET /v1/activity/transactions Elysium, HyperEVM
  HyperEVM user transactions, those that created a contract, and the fees they paid, per bucket.
• Chain wallets GET /v1/activity/wallets Elysium, HyperEVM
  HyperEVM distinct senders of user transactions, and the new ones (first user transaction on the layer), per bucket.
• Chain dex volume GET /v1/activity/volume Elysium, HyperEVM
  HyperEVM swaps on the layer's pools, distinct traders, and their USD volume (wash round trips left out), per bucket.
• Chain launches GET /v1/activity/launches Elysium, HyperEVM
  HyperEVM tokens launched on a launchpad and ERC-20 tokens created (spam left out), per bucket.
• Chain bridged in GET /v1/activity/bridged Elysium, HyperEVM
  HyperEVM deposits from the parent chain: count, distinct depositors and USD value, per bucket.
• Block GET /v1/blocks/{number} Elysium, HyperEVM
  One HyperEVM block and every transaction in it: who called what, swaps, gas and fees.
• Transaction GET /v1/tx/{hash} Elysium, HyperEVM
  One transaction: status, gas, decoded transfers, swaps and liquidity, bridge legs and journey.
• Transaction status GET /v1/tx/{hash}/status Elysium, HyperEVM
  Where a transaction sent through our HyperEVM RPC is: which upstreams accepted it, its block, or replaced / dropped.
• Transaction status stream WS elysium.tx.status | hyperevm.tx.status Elysium, HyperEVM
  The inclusion status of one transaction sent through POST /v1/HyperEVM/rpc (eth_sendRawTransaction): the upstreams that accepted it, then its block (success or reverted), or replaced / dropped. A hash not sent through our RPC gets its status from the chain once (included or unknown) and no later frame. With `from` instead of `hash`: every transaction of up to 10 senders, those your account sent through our RPC from the moment an upstream accepts them, the others once they are in a block.
• Sent transactions GET /v1/rpc/sent Elysium, HyperEVM
  The transactions your account sent through our HyperEVM RPC, newest first, with where each one is.
• EVM JSON-RPC POST /v1/elysium/rpc | /v1/hyperevm/rpc Elysium, HyperEVM
  Free HyperEVM RPC by Femtos, read and send (eth_sendRawTransaction), for wallets, dapps and bots, not for indexing (use the Femtos API for history): no key 5 requests a second per IP; a key its plan's limits (free 50/s, 15 transactions/s, up to 2000/s), never metered; batches of 50 with a key, eth_getLogs over 1,000 blocks at most, state of the last 128 blocks only.
• Stream stats WS stats HyperCore
  Our HyperCore stream health, once a second.
• Check your key GET /v1/whoami Elysium, HyperCore, HyperEVM
  Answers the name your key is registered under, its tier, billing state and the limits in force.
• OpenAPI document GET /v1/openapi.json Elysium, HyperCore, HyperEVM
  The OpenAPI 3.1 contract of every REST call, public.

More

• This page as Markdown
• The whole API reference
• What Elysium serves
• What HyperEVM serves
• The whole API in one Markdown file
• OpenAPI 3.1 document

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