# orbit Chain Reads

> Live EVM chain reads for agents across Base, Ethereum, Arbitrum, Optimism and Polygon: gas fees, wallet balances (native + USDC), transaction status, ERC-20 metadata and ENS resolution. Every answer is read from public RPC nodes at call time. $0.001 per call. Pay per call with x402 (USDC on Base, no account, no API key). Free MCP (trimmed sample output) at https://orbit-chain.orbit-builder.workers.dev/mcp. By orbit-builder.

## Paid endpoints (x402 v2, exact, eip155:8453, USDC 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, payTo 0x9Da4B249B8afa7818de5BFf7eEd8b13e6feeb9b3). Bad input is rejected with 400 before payment; upstream errors return >=400 and are never settled. A call with no parameters runs the example input shown.

- EVM gas fees ($0.001): GET or POST https://orbit-chain.orbit-builder.workers.dev/v1/gas — Live EIP-1559 gas for Base, Ethereum, Arbitrum, Optimism, Polygon (or all): next base fee, gas price, slow/standard/fast max fee + priority fee in gwei (median of last 20 blocks' 10/50/90th percentile tips), block utilisation, cost of a native transfer. Read from public RPC nodes at call time.
  params: chain (base (default), ethereum, arbitrum, optimism, polygon, or all)
  example: https://orbit-chain.orbit-builder.workers.dev/v1/gas?chain=base
- Wallet balance (native + USDC) ($0.001): GET or POST https://orbit-chain.orbit-builder.workers.dev/v1/balance — Balance of any EVM address on Base, Ethereum, Arbitrum, Optimism or Polygon (or all 5): native coin and native USDC (atomic + decimal), transaction count (nonce), whether it is a contract or an EIP-7702 delegated EOA, explorer link. Live from public RPC.
  params: address* (0x EVM address); chain (base (default), ethereum, arbitrum, optimism, polygon, or all)
  example: https://orbit-chain.orbit-builder.workers.dev/v1/balance?address=0x4200000000000000000000000000000000000006&chain=base
- Transaction status ($0.001): GET or POST https://orbit-chain.orbit-builder.workers.dev/v1/tx — Status of an EVM transaction hash on Base, Ethereum, Arbitrum, Optimism or Polygon: success/failed/pending, block, confirmations, from, to, value, nonce, gas used, effective gas price, fee paid in native coin, log count, contract created. Unknown hash returns 404 (not charged).
  params: hash* (0x 64-hex transaction hash); chain (base (default), ethereum, arbitrum, optimism, polygon)
  example: https://orbit-chain.orbit-builder.workers.dev/v1/tx?hash=0x0b3173e7dec25b44d1aa86262e10beea271c6be04423c8fe82a1eedf7bf9d742&chain=base
- ERC-20 token metadata ($0.001): GET or POST https://orbit-chain.orbit-builder.workers.dev/v1/token — ERC-20 metadata read directly from the contract on Base, Ethereum, Arbitrum, Optimism or Polygon: name, symbol, decimals, total supply (raw + decimal), bytecode size, and optionally one holder's balance. Non-contract address returns 404 (not charged). Raw chain data, no price or risk opinion.
  params: address* (token contract address); chain (base (default), ethereum, arbitrum, optimism, polygon); holder (optional address to read balanceOf for)
  example: https://orbit-chain.orbit-builder.workers.dev/v1/token?address=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913&chain=base
- ENS resolve (name ⇄ address) ($0.001): GET or POST https://orbit-chain.orbit-builder.workers.dev/v1/ens — Resolve an ENS name (vitalik.eth, also *.base.eth via CCIP) to its Ethereum address, or reverse-resolve an address to its primary ENS name (forward-verified), plus avatar/url/twitter/github text records when set. Live from Ethereum mainnet via public RPC. No record returns 404 (not charged).
  params: name (ENS name, e.g. vitalik.eth); address (or an address for reverse lookup)
  example: https://orbit-chain.orbit-builder.workers.dev/v1/ens?name=vitalik.eth

Bad input returns 400 before payment; not-found and upstream errors return 4xx/5xx and are never settled.

## Free

- https://orbit-chain.orbit-builder.workers.dev/v1/preview?tool=<name> (runs the fixed example input live)
- MCP (streamable HTTP, JSON-RPC 2.0 POST): https://orbit-chain.orbit-builder.workers.dev/mcp — tools: gas_fees, wallet_balance, tx_status, token_info, ens_resolve
- https://orbit-chain.orbit-builder.workers.dev/openapi.json, https://orbit-chain.orbit-builder.workers.dev/.well-known/x402, https://orbit-chain.orbit-builder.workers.dev/.well-known/agent.json

## Data sources
- gas_fees: eth_feeHistory / eth_gasPrice on public RPC nodes (publicnode.com, chain foundations)
- wallet_balance: eth_getBalance / eth_getTransactionCount / eth_getCode / USDC balanceOf on public RPC nodes
- tx_status: eth_getTransactionByHash / eth_getTransactionReceipt on public RPC nodes
- token_info: eth_call name()/symbol()/decimals()/totalSupply()/balanceOf() on public RPC nodes
- ens_resolve: ENS Universal Resolver on Ethereum mainnet (public RPC)