Networks
| Network | Chain ID | CAIP-2 identifier | Status |
|---|---|---|---|
| Base | 8453 | eip155:8453 | Default |
| Ethereum | 1 | eip155:1 | Supported |
| Optimism | 10 | eip155:10 | Supported |
| Arbitrum | 42161 | eip155:42161 | Supported |
| Polygon | 137 | eip155:137 | Supported |
Testnets
| Network | Chain ID | CAIP-2 identifier |
|---|---|---|
| Base Sepolia | 84532 | eip155:84532 |
| Ethereum Sepolia | 11155111 | eip155:11155111 |
Default network
Base is the default network for payments. Most endpoints accept USDC on Base, and transaction fees are significantly lower than Ethereum mainnet. Usenpx agentcash balance or the MCP get_balance tool for your total USDC balance. Use npx agentcash accounts or the MCP list_accounts tool when you need the per-network balances, wallet addresses, and deposit links.
Payment network selection
The endpoint determines which network to use. The402 Payment Required response includes the expected network in its payment challenge. AgentCash reads this and pays on the correct chain automatically.