Current Ethereum development tools, frameworks, libraries, RPCs, and block explorers. What actually works today for building on Ethereum. Includes tool discovery for AI agents — MCPs, abi.ninja, Foundry, Scaffold-ETH 2, Hardhat, and more. Use when setting up a dev environment, choosing tools, or when an agent needs to discover what's available.
Blockscout MCP server exists: https://mcp.blockscout.com/mcp — gives AI agents structured blockchain data via Model Context Protocol. This is cutting-edge infra as of Feb 2026.
abi.ninja is essential: https://abi.ninja — paste any verified contract address, get a UI to call any function. Zero setup. Supports mainnet + all major L2s. Perfect for agent-driven contract exploration.
x402 has production SDKs: @x402/fetch (TS), x402 (Python), github.com/coinbase/x402/go — production-ready libraries for HTTP payments.
Foundry and Hardhat 3 are both legitimate choices in 2026. Foundry: faster, Solidity-native. Hardhat 3: TypeScript-first, mature plugin ecosystem.
When an agent needs to interact with Ethereum:
cast send or ethers.js/viemcast interface (CLI)anvil, test locallyforge create or forge scriptforge verify-contract or Etherscan APIA Model Context Protocol server giving AI agents structured blockchain data:
Why this matters: Instead of scraping Etherscan or making raw API calls, agents get structured, type-safe blockchain data via MCP.
URL: https://abi.ninja — Paste any contract address → interact with all functions. Multi-chain. Zero setup.
TypeScript:
npm install @x402/core @x402/evm @x402/fetch @x402/express
import { x402Fetch } from '@x402/fetch';
import { createWallet } from '@x402/evm';
const wallet = createWallet(privateKey);
const response = await x402Fetch('https://api.example.com/data', {
wallet,
preferredNetwork: 'eip155:8453' // Base
});
Python: pip install x402
Go: go get github.com/coinbase/x402/go
Docs: https://www.x402.org | https://github.com/coinbase/x402
npx create-eth@latestyarn ipfs (BuidlGuidl IPFS)| Need | Tool |
|---|---|
| Rapid prototyping / full dApps | Scaffold-ETH 2 |
| Contract-focused dev | Foundry (forge + cast + anvil) · or Hardhat 3 if TypeScript-first |
| Quick contract interaction | abi.ninja (browser) or cast (CLI) |
| React frontends | wagmi + viem (or SE2 which wraps these) |
| Agent blockchain reads | Blockscout MCP |
| Agent payments | x402 SDKs |
# Read contract
cast call 0xAddr "balanceOf(address)(uint256)" 0xWallet --rpc-url $RPC
# Send transaction
cast send 0xAddr "transfer(address,uint256)" 0xTo 1000000 --private-key $KEY --rpc-url $RPC
# Gas price
cast gas-price --rpc-url $RPC
# Decode calldata
cast 4byte-decode 0xa9059cbb...
# ENS resolution
cast resolve-name vitalik.eth --rpc-url $RPC
# Fork mainnet locally
anvil --fork-url $RPC
Free (testing):
https://eth.llamarpc.com — LlamaNodes, no keyhttps://rpc.ankr.com/eth — Ankr, free tierPaid (production):
Community: rpc.buidlguidl.com
| Network | Explorer | API |
|---|---|---|
| Mainnet | https://etherscan.io | https://api.etherscan.io |
| Arbitrum | https://arbiscan.io | Etherscan-compatible |
| Base | https://basescan.org | Etherscan-compatible |
| Optimism | https://optimistic.etherscan.io | Etherscan-compatible |
Model Context Protocol — standard for giving AI agents structured access to external systems.
MCP servers are composable — agents can use multiple together.
Fork mainnet locally:
anvil --fork-url https://eth.llamarpc.com
# Now test against real contracts with fake ETH at http://localhost:8545
Primary testnet: Sepolia (Chain ID: 11155111). Goerli and Rinkeby are deprecated.
| Network | Faucet |
|---|---|
| Sepolia | https://sepolia-faucet.pk910.de/ |
| Sepolia | https://www.infura.io/faucet/sepolia |
| Multiple | https://www.alchemy.com/faucets |
| Multiple | https://cloud.google.com/application/web3/faucet/ethereum |
| Multiple | https://faucet.quicknode.com/drip |
| Multiple | https://getblock.io/faucet/ |
Once you have Sepolia ETH you can bridge it to any L2 using each L2's testnet bridge then you will have ETH on that L2 testnet.