If you've wired an MCP server into an agent, you've probably done something like this: { "mcpServers" : { "billing" : { "command" : "npx" , "args" : [ "billing-mcp" ], "env" : { "BILLING_API_KEY" : "sk-live-... " } } } } It works. It's also handing your live billing key to the least trustworthy ...
Source: [Dev.to](https://dev.to/rojaneerdev/keep-your-api-keys-out-of-your-ai-agent-a-credential-pattern-for-mcp-servers-4cmo)