Celo RPC Interactions

This skill covers interacting with the Celo blockchain via RPC endpoints.

When to Use

•Reading account balances (CELO and tokens)
•Querying transaction data
•Getting block information
•Interacting with Celo via viem or cast

Network Information

Network	Chain ID	RPC Endpoint
Celo Mainnet	42220	https://forno.celo.org
Celo Sepolia	11142220	https://forno.celo-sepolia.celo-testnet.org

Forno is a rate-limited, best-effort service. For production, use a dedicated RPC provider.

Alternative RPC Providers

Provider	Mainnet	Testnet
Alchemy	https://celo-mainnet.g.alchemy.com/v2/{API_KEY}	https://celo-sepolia.g.alchemy.com/v2/{API_KEY}
Infura	https://celo-mainnet.infura.io/v3/{API_KEY}	https://celo-sepolia.infura.io/v3/{API_KEY}
Ankr	https://rpc.ankr.com/celo	https://rpc.ankr.com/celo_testnet
QuickNode	Custom endpoint via dashboard	Custom endpoint via dashboard

Block Explorers

•Celo Mainnet: https://celoscan.io
•Celo Sepolia: https://sepolia.celoscan.io

Using viem with Celo

Installation

bash

npm install viem

Basic Setup

typescript

import { createPublicClient, http } from "viem";
import { celo, celoSepolia } from "viem/chains";

// Mainnet client
const publicClient = createPublicClient({
  chain: celo,
  transport: http("https://forno.celo.org"),
});

// Testnet client (Celo Sepolia)
const testnetClient = createPublicClient({
  chain: celoSepolia,
  transport: http("https://forno.celo-sepolia.celo-testnet.org"),
});

Reading Balances

typescript

// Get CELO balance
const balance = await publicClient.getBalance({
  address: "0x...",
});
console.log("Balance:", balance, "wei");

// Get token balance (e.g., cUSD)
const cUSD = "0x765de816845861e75a25fca122bb6898b8b1282a";
const tokenBalance = await publicClient.readContract({
  address: cUSD,
  abi: [
    {
      name: "balanceOf",
      type: "function",
      stateMutability: "view",
      inputs: [{ name: "account", type: "address" }],
      outputs: [{ type: "uint256" }],
    },
  ],
  functionName: "balanceOf",
  args: ["0x..."],
});

Getting Block Data

typescript

// Get latest block number
const blockNumber = await publicClient.getBlockNumber();

// Get block by number
const block = await publicClient.getBlock({
  blockNumber: 12345678n,
});

// Get block by hash
const blockByHash = await publicClient.getBlock({
  blockHash: "0x...",
});

Getting Transaction Data

typescript

// Get transaction by hash
const tx = await publicClient.getTransaction({
  hash: "0x...",
});

// Get transaction receipt
const receipt = await publicClient.getTransactionReceipt({
  hash: "0x...",
});

Using cast (Foundry)

Reading Data

bash

# Get CELO balance
cast balance 0x... --rpc-url https://forno.celo.org

# Get block number
cast block-number --rpc-url https://forno.celo.org

# Get block details
cast block 12345678 --rpc-url https://forno.celo.org

# Get transaction
cast tx 0x... --rpc-url https://forno.celo.org

# Call view function
cast call 0x765de816845861e75a25fca122bb6898b8b1282a \
  "balanceOf(address)(uint256)" \
  0x... \
  --rpc-url https://forno.celo.org

# Get storage slot
cast storage 0x... 0 --rpc-url https://forno.celo.org

Chain Information

bash

# Get chain ID
cast chain-id --rpc-url https://forno.celo.org

# Get gas price
cast gas-price --rpc-url https://forno.celo.org

Using curl (Raw RPC)

Get Balance

bash

curl -X POST https://forno.celo.org \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getBalance",
    "params": ["0x...", "latest"],
    "id": 1
  }'

Get Block Number

bash

curl -X POST https://forno.celo.org \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_blockNumber",
    "params": [],
    "id": 1
  }'

Standard EVM RPC Methods

All standard Ethereum JSON-RPC methods are supported:

Method	Description
eth_blockNumber	Returns the current block number
eth_getBalance	Returns the balance of an address
eth_getTransactionByHash	Returns transaction by hash
eth_getTransactionReceipt	Returns transaction receipt
eth_call	Executes a call without creating a transaction
eth_estimateGas	Estimates gas for a transaction
eth_gasPrice	Returns current gas price
eth_getBlockByNumber	Returns block by number
eth_getBlockByHash	Returns block by hash
eth_getLogs	Returns logs matching filter
eth_sendRawTransaction	Sends a signed transaction

Additional Resources

•rpc-providers.md - Full list of RPC providers