use-usdclisted

## Overview USDC is Circle's stablecoin deployed across multiple blockchain ecosystems. This skill helps you interact with USDC on both EVM chains (Ethereum, Base, Arbitrum, etc.) and Solana. It covers balance checks, transfers, approvals, and transfer verification. ## Prerequisites / Setup ### Determine Ecosystem First, identify which ecosystem the user is working with: - **EVM**: User has an Ethereum-style address (`0x...`) or mentions Ethereum, Base, Arbitrum, Polygon, etc. - **Solana**: User has a base58 address or mentions Solana, Devnet, Phantom, Solflare, etc. - **Unclear**: Ask which ecosystem before proceeding. ### Dependencies **EVM:** ```bash npm install viem ``` **Solana:** ```bash npm install @solana/kit @solana-program/token ws dotenv bs58 ``` ### Environment Variables See ecosystem-specific guides: - **EVM**: Private key handling covered in `references/evm.md` - **Solana**: Private key handling covered in `references/solana.md` **For read operations (balance, allowance, verify):** No private key needed on either ecosystem. ## Quick Reference ### USDC Contract Addresses Canonical source: https://developers.circle.com/stablecoins/usdc-contract-addresses #### EVM Testnet | Chain | Chain ID | USDC Address | |-------|----------|-------------| | Arc Testnet | 5042002 | `0x3600000000000000000000000000000000000000` | | Ethereum Sepolia | 11155111 | `0x1c7D4B196Cb0C7B01d743Fbc6116a902379C7238` | | Base Sepolia | 84532 | `0x036CbD53842c5426634e7929541eC23