/rpc

name: rpc
description: Use when the user needs raw blockchain JSON-RPC access — contract reads (eth_call), native balances, blocks, transactions, logs, gas estimates, or any chain-native RPC method across 40 chains. One endpoint per chain via BlockRun's Tatum-backed gateway, $0.0030 per call, no node, no API key. Prefer blockrun_price / blockrun_dex / blockrun_surf when they already cover the question.
triggers:
  - "rpc"
  - "json-rpc"
  - "eth_call"
  - "contract read"
  - "raw chain"
  - "node access"
  - "blockchain rpc"
  - "getBalance"
  - "block number"
  - "transaction receipt"
  - "event logs"
  - "tatum"

Multi-chain RPC — every supported chain, one tool

`blockrun_rpc` POSTs a standard JSON-RPC 2.0 body to `/v1/rpc/{network}`. Flat **$0.0030 per call** ($0.002 base + the $0.001 transaction fee). A JSON-RPC **batch array charges per element but pays the flat fee only once** — $0.002 × n + $0.001, so a batch of 3 costs $0.0070 where three separate calls cost $0.0090. Batch whenever you can. Settlement in USDC via x402. Responses are cached briefly server-side for identical read calls (`X-Cache: HIT` is free of upstream latency but still billed).

When to use which tool

| Question | Tool | |---|---| | "What's ETH trading at?" | `blockrun_price` (free) | | "PEPE/WETH pool liquidity?" | `blockrun_dex` (free) | | "What's this wallet labeled as / holding?" | `blockrun_surf` | | "Call `balanceOf(0x...)` on this ERC-20" | **`blockrun_rpc`** | | "Latest block / tx receipt / event logs / gas price" | **`blockrun_rpc`** | | "Solana account info / slot / signatures" | **`blockrun_rpc`** |

Networks

EVM (use `eth_*` methods):

| Key | Chain | | Key | Chain | |---|---|---|---|---| | `ethereum` | Ethereum | | `zksync` | zkSync Era | | `base` | Base | | `berachain` | Berachain | | `arbitrum` | Arbitrum One | | `unichain` | Unichain | | `arbitrum-nova` | Arbitrum Nova | | `monad` | Monad | | `optimism` | Optimism | | `chiliz` | Chiliz | | `polygon` | Polygon | | `moonbeam` | Moonbeam | | `bsc` | BNB Smart Chain | | `aurora` | Aurora | | `avalanche` | Avalanche C-Chain | | `flare` | Flare | | `fantom` | Fantom | | `oasis` | Oasis Sapphire | | `cronos` | Cronos | | `kaia` | Kaia (Klaytn) | | `celo` | Celo | | `sonic` | Sonic | | `gnosis` | Gnosis | | `xdc` | XDC Network | | `abstract` | Abstract | | `hyperevm` | HyperEVM | | `plume` | Plume | | `ronin` | Ronin | | `rootstock` | Rootstock (RSK) | | | |

Non-EVM (chain-native methods):

| Key | Chain | Method family | |---|---|---| | `solana` | Solana | `getSlot`, `getBalance`, `getAccountInfo`, `getSignaturesForAddress` | | `bitcoin` | Bitcoin | `getblockchaininfo`, `getblockcount`, `getrawtransaction` | | `litecoin` / `dogecoin` / `bitcoin-cash` / `zcash` | UTXO chains | Bitcoin-style RPC | | `near` | NEAR | `status`, `query` | | `sui` | Sui | `sui_getLatestCheckpointSequenceNumber`, `suix_getBalance` | | `ripple` | XRP Ledger | `account_info`, `ledger` | | `polkadot` / `kusama` | Substrate | `chain_getHeader`, `state_getStorage` |

Unknown-but-wellformed slugs pass through to the Tatum gateway untouched — newly added chains work without an MCP update. A bad slug returns HTTP 400 with the supported list (no charge).

Recipes

ERC-20 balance (eth_call):

blockrun_rpc({
  network: "base",
  method: "eth_call",
  params: [{
    to: "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",   // USDC on Base
    data: "0x70a08231000000000000000000000000<ADDRESS_NO_0x_PADDED_TO_32B>"
  }, "latest"]
})

Native balance: `method: "eth_getBalance", params: ["0x...", "latest"]` Tx receipt: `method: "eth_getTransactionReceipt", params: ["0x<txhash>"]` Event logs: `method: "eth_getLogs", params: [{ fromBlock, toBlock, address, topics }]` — keep ranges small; huge ranges are rejected upstream (no charge). Gas: `method: "eth_gasPrice"` / `eth_estimateGas`

Solana token account: `network: "solana", method: "getTokenAccountsByOwner", params: ["<owner>", {"mint": "<mint>"}, {"encoding": "jsonParsed"}]`

Batch (charged per element, flat fee paid once — 3 calls = $0.0070, vs $0.0090 sent separately):

blockrun_rpc({ network: "ethereum", body: [
  { jsonrpc: "2.0", id: 1, method: "eth_blockNumber" },
  { jsonrpc: "2.0", id: 2, method: "eth_gasPrice" },
  { jsonrpc: "2.0", id: 3, method: "eth_chainId" }
]})

Failure semantics

• Upstream timeout / 5xx → **no charge**, retry safe.
• Malformed body / bad network → HTTP 400, **no charge**.
• JSON-RPC-level errors (e.g. revert on `eth_call`) come back inside `result.error` — the call **is** charged (the node did the work).