Alchemy install auth
'Install the Alchemy SDK and configure API key authentication for Web3 development.From its SKILL.md
npx -y skills add jeremylongshore/claude-code-plugins-plus-skills --skill alchemy-install-authAssembled from the repository path, not quoted from the project. Check it against their README if it does not work.
What its file declares
Copied from the file, not written here
The file declares its own license as MIT. That is the author’s claim about this one file, and it is not the same thing as the license GitHub reports for the repository, which is listed with the other numbers below.
SKILL.md
4.0 KB, 908 tokens by cl100k_base, as published. Nobody here has run it
Alchemy Install & Auth
Overview
Install the alchemy-sdk npm package and configure API authentication. Alchemy provides blockchain infrastructure (RPC nodes, Enhanced APIs, NFT APIs, webhooks) across Ethereum, Polygon, Arbitrum, Optimism, Base, and Solana.
Prerequisites
- Node.js 18+ (or Python 3.10+ for alchemy-sdk Python)
- Free Alchemy account at alchemy.com
- API key from Alchemy Dashboard
Instructions
Step 1: Install the Alchemy SDK
# JavaScript/TypeScript (official SDK)
npm install alchemy-sdk
# Python (community SDK)
pip install alchemy-sdk
Step 2: Create an Alchemy App
- Go to dashboard.alchemy.com
- Click "Create new app"
- Select chain: Ethereum, Polygon, Arbitrum, Optimism, Base, or Solana
- Select network: Mainnet, Sepolia (testnet), or Mumbai
- Copy the API key
Step 3: Configure Environment
# Set environment variable
export ALCHEMY_API_KEY="your-api-key-here"
# Or create .env file
cat > .env << 'EOF'
ALCHEMY_API_KEY=your-api-key-here
ALCHEMY_NETWORK=ETH_MAINNET
EOF
echo ".env" >> .gitignore
Step 4: Initialize and Verify
// src/alchemy-client.ts
import { Alchemy, Network } from 'alchemy-sdk';
const alchemy = new Alchemy({
apiKey: process.env.ALCHEMY_API_KEY,
network: Network.ETH_MAINNET,
});
// Verify connection
async function verifyConnection() {
const blockNumber = await alchemy.core.getBlockNumber();
console.log(`Connected! Latest block: ${blockNumber}`);
return blockNumber;
}
verifyConnection().catch(console.error);
Step 5: Multi-Chain Configuration
// src/config/chains.ts
import { Alchemy, Network } from 'alchemy-sdk';
// Create clients for multiple chains
const chains = {
ethereum: new Alchemy({ apiKey: process.env.ALCHEMY_API_KEY, network: Network.ETH_MAINNET }),
polygon: new Alchemy({ apiKey: process.env.ALCHEMY_API_KEY, network: Network.MATIC_MAINNET }),
arbitrum: new Alchemy({ apiKey: process.env.ALCHEMY_API_KEY, network: Network.ARB_MAINNET }),
optimism: new Alchemy({ apiKey: process.env.ALCHEMY_API_KEY, network: Network.OPT_MAINNET }),
base: new Alchemy({ apiKey: process.env.ALCHEMY_API_KEY, network: Network.BASE_MAINNET }),
};
export default chains;
Supported Networks
| Chain | Network Enum | Mainnet | Testnet |
|---|---|---|---|
| Ethereum | ETH_MAINNET | Yes | Sepolia |
| Polygon | MATIC_MAINNET | Yes | Amoy |
| Arbitrum | ARB_MAINNET | Yes | Sepolia |
| Optimism | OPT_MAINNET | Yes | Sepolia |
| Base | BASE_MAINNET | Yes | Sepolia |
| Solana | SOL_MAINNET | Yes | Devnet |
Output
alchemy-sdkinstalled in node_modules- API key configured in environment
- Verified connection with latest block number
- Multi-chain client configuration ready
Error Handling
| Error | Cause | Solution |
|---|---|---|
Must provide apiKey | Missing env var | Set ALCHEMY_API_KEY in environment |
401 Unauthorized | Invalid API key | Verify key in Alchemy Dashboard |
429 Rate Limit | Free tier exceeded | Upgrade plan or reduce request rate |
ECONNREFUSED | Network blocked | Ensure HTTPS to *.g.alchemy.com allowed |
Resources
Next Steps
Proceed to alchemy-hello-world for your first blockchain query.
What ships with it
Read from the repository
Just SKILL.md. No reference files, no scripts.