🛡️ How to Stop Your AI Agent from Sending 10,000 Emails in a Loop

You ship an AI agent that can send emails. It works great in testing. Then one night, the agent hits a retry loop. A flaky API responds slowly, the agent interprets the delay as failure, and it tries again. And again. By morning, a single user has received 847 confirmation emails. Your support inbox is on fire. Your API provider has suspended your account. This isn't a hypothetical. It's the kind of thing that happens when you give agents real tools and don't put guardrails around how often they can use them. In the first article, I introduced Guardio - a policy enforcement proxy that sits between your AI agent and the outside world. Today, I want to show you one of its newest built-in policies: rate limiting. Why Rate Limiting Is Different for AI Agents With traditional APIs, rate limiting is simple: a client sends too many requests, the server returns a 429, and the client backs off. Problem solved. AI agents are messier. They can retry silently without you noticing until it's too la