# AgentCash > One balance, access to every API on the internet. AgentCash is an MCP server and wallet that lets AI agents call payment-protected APIs using x402 micropayments. Fund a single USDC balance, install the MCP server in any compatible AI agent (Claude, Cursor, Codex, etc.), and your agent can buy data, tools, and capabilities from any participating API — no API keys required. ## How it works 1. Install the AgentCash MCP server in your AI agent. 2. Fund your wallet with USDC on Base, Solana, or Tempo. 3. Your agent discovers and calls paid APIs on demand, paying per call automatically via x402. ## Key concepts - **x402**: HTTP-native micropayment protocol. APIs return 402 Payment Required; the agent's wallet pays automatically. - **MCP (Model Context Protocol)**: The standard interface that lets AI agents use external tools, including AgentCash. - **Pay-per-call**: No subscriptions, no API keys. Each API call is paid individually in USDC. ## Links - Install guide: https://agentcash.dev/install - Claude-specific setup: https://agentcash.dev/install/claude - API directory: https://agentcash.dev/apis - Blog: https://agentcash.dev/blog - Learn (guides): https://agentcash.dev/learn - Documentation: https://agentcash.dev/guide - Resources: https://agentcash.dev/resources