Why x402 Payment-Based MCP Servers Are Safer Than API Keys (And Where They Are Not) The MCP security post making rounds this week found that ~30% of public MCP servers expose hardcoded credentials in their configs or tool descriptions. That is a real problem. But it is a problem that disappears when you flip the payment model. The Shift: From Static Secrets to Signed Payments Traditional MCP servers gate access with API keys. The key is a static secret that lives in config files, environment variables, and sometimes — as the security audit showed — directly in tool descriptions where the LLM can read them. x402 servers do not use API keys. They use HTTP 402 Payment Required responses. The credential is a signed USDC micropayment authorization, generated per-request, valid for seconds, settled on-chain. What this eliminates: No sk-...…