Web3 Frontend

Web3 Frontend Skill

Master Web3 frontend development with wallet integration, modern libraries (viem/wagmi), and production dApp patterns.

Quick Start

# Invoke this skill for Web3 frontend development
Skill("web3-frontend", topic="wallet", framework="react")

Topics Covered

1. Wallet Integration

Connect users to Web3:

• RainbowKit: Beautiful wallet modal
• WalletConnect: Mobile support
• Account Abstraction: ERC-4337
• Multi-chain: Network switching

2. Transaction Management

Handle blockchain interactions:

• Write Operations: Contract writes
• State Tracking: Pending, confirmed
• Gas Estimation: Fee display
• Error Handling: User-friendly messages

3. Signing & Auth

Verify user identity:

• EIP-712: Typed data signing
• SIWE: Sign-In with Ethereum
• Permit: Gasless approvals
• Message Signing: Personal sign

4. React Hooks

Modern patterns with wagmi:

• useAccount: Connection state
• useWriteContract: Transactions
• useReadContract: Data fetching
• useWaitForTransactionReceipt: Confirmations

Code Examples

Connect Wallet

'use client';

import { ConnectButton } from '@rainbow-me/rainbowkit';
import { useAccount } from 'wagmi';

export function WalletConnect() {
  const { address, isConnected } = useAccount();

  return (
    <div>
      <ConnectButton />
      {isConnected && <p>Connected: {address}</p>}
    </div>
  );
}

Write Contract

import { useWriteContract, useWaitForTransactionReceipt } from 'wagmi';
import { parseEther } from 'viem';

export function MintButton() {
  const { writeContract, data: hash, isPending } = useWriteContract();
  const { isLoading, isSuccess } = useWaitForTransactionReceipt({ hash });

  const mint = () => {
    writeContract({
      address: '0x...',
      abi: [...],
      functionName: 'mint',
      args: [1n],
      value: parseEther('0.08'),
    });
  };

  return (
    <button onClick={mint} disabled={isPending || isLoading}>
      {isPending ? 'Confirm in wallet...' :
       isLoading ? 'Minting...' :
       isSuccess ? 'Minted!' : 'Mint NFT'}
    </button>
  );
}

Sign Typed Data (EIP-712)

import { useSignTypedData } from 'wagmi';

const DOMAIN = {
  name: 'My App',
  version: '1',
  chainId: 1,
  verifyingContract: '0x...',
};

export function useSignOrder() {
  const { signTypedDataAsync } = useSignTypedData();

  const sign = async (order: Order) => {
    return await signTypedDataAsync({
      domain: DOMAIN,
      types: { Order: [...] },
      primaryType: 'Order',
      message: order,
    });
  };

  return { sign };
}

Error Handling

export function parseError(error: unknown): string {
  const msg = error instanceof Error ? error.message : String(error);

  if (msg.includes('user rejected')) return 'Transaction cancelled';
  if (msg.includes('insufficient funds')) return 'Insufficient balance';
  if (msg.includes('execution reverted')) {
    const reason = msg.match(/reason="([^"]+)"/)?.[1];
    return reason || 'Transaction would fail';
  }

  return 'Transaction failed';
}

Package Setup

npm install wagmi viem @rainbow-me/rainbowkit @tanstack/react-query

// providers/Web3.tsx
import { WagmiProvider } from 'wagmi';
import { RainbowKitProvider } from '@rainbow-me/rainbowkit';
import { QueryClientProvider, QueryClient } from '@tanstack/react-query';
import { config } from './config';

const queryClient = new QueryClient();

export function Web3Provider({ children }) {
  return (
    <WagmiProvider config={config}>
      <QueryClientProvider client={queryClient}>
        <RainbowKitProvider>{children}</RainbowKitProvider>
      </QueryClientProvider>
    </WagmiProvider>
  );
}

Common Patterns

Common Pitfalls

Troubleshooting

"Wallet not connecting"

// Ensure client-side only
import dynamic from 'next/dynamic';

const ConnectButton = dynamic(
  () => import('./ConnectButton'),
  { ssr: false }
);

"Transaction pending forever"

Check gas settings or speed up:

await wallet.sendTransaction({
  ...tx,
  maxFeePerGas: tx.maxFeePerGas * 120n / 100n,
});

Security Checklist

• [ ] Never expose private keys
• [ ] Validate contract addresses
• [ ] Sanitize user inputs
• [ ] Use proper error boundaries
• [ ] Implement CSP headers

Cross-References

• Bonded Agent: 05-web3-frontend
• Related Skills: ethereum-development, solidity-development

Version History

Web3 Frontend Guide

Overview

This guide provides comprehensive documentation for the web3-frontend skill in the custom-plugin-blockchain plugin.

Category: General

Quick Start

Prerequisites

• Familiarity with general concepts
• Development environment set up
• Plugin installed and configured

Basic Usage

# Invoke the skill
claude "web3-frontend - [your task description]"

# Example
claude "web3-frontend - analyze the current implementation"

Core Concepts

Key Principles

1. Consistency - Follow established patterns 2. Clarity - Write readable, maintainable code 3. Quality - Validate before deployment

Best Practices

• Always validate input data
• Handle edge cases explicitly
• Document your decisions
• Write tests for critical paths

Common Tasks

Task 1: Basic Implementation

# Example implementation pattern
def implement_web3_frontend(input_data):
    """
    Implement web3-frontend functionality.

    Args:
        input_data: Input to process

    Returns:
        Processed result
    """
    # Validate input
    if not input_data:
        raise ValueError("Input required")

    # Process
    result = process(input_data)

    # Return
    return result

Task 2: Advanced Usage

For advanced scenarios, consider:

• Configuration customization via assets/config.yaml
• Validation using scripts/validate.py
• Integration with other skills

Troubleshooting

Common Issues

Related Resources

• SKILL.md - Skill specification
• config.yaml - Configuration options
• validate.py - Validation script

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Last updated: 2025-12-30

Web3 Frontend Patterns

Design Patterns

Pattern 1: Input Validation

Always validate input before processing:

def validate_input(data):
    if data is None:
        raise ValueError("Data cannot be None")
    if not isinstance(data, dict):
        raise TypeError("Data must be a dictionary")
    return True

Pattern 2: Error Handling

Use consistent error handling:

try:
    result = risky_operation()
except SpecificError as e:
    logger.error(f"Operation failed: {e}")
    handle_error(e)
except Exception as e:
    logger.exception("Unexpected error")
    raise

Pattern 3: Configuration Loading

Load and validate configuration:

import yaml

def load_config(config_path):
    with open(config_path) as f:
        config = yaml.safe_load(f)
    validate_config(config)
    return config

Anti-Patterns to Avoid

❌ Don't: Swallow Exceptions

# BAD
try:
    do_something()
except:
    pass

✅ Do: Handle Explicitly

# GOOD
try:
    do_something()
except SpecificError as e:
    logger.warning(f"Expected error: {e}")
    return default_value

Category-Specific Patterns: General

Recommended Approach

1. Start with the simplest implementation 2. Add complexity only when needed 3. Test each addition 4. Document decisions

Common Integration Points

• Configuration: assets/config.yaml
• Validation: scripts/validate.py
• Documentation: references/GUIDE.md

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Pattern library for web3-frontend skill