Prompt Canaries: Early Warning Signs Your AI Workflow Is Degrading

In coal mines, canaries detected poison gas before miners could smell it. In AI workflows, you need the same thing: small, cheap signals that tell you something is going wrong before your output quality collapses. I call them prompt canaries, and after six months of running AI-assisted coding workflows, they're the single most valuable quality practice I've adopted. The Problem AI workflow degradation is slow and silent. Your prompts worked great in January. By March, you're getting subtly worse output and you can't pinpoint when it started. Without canaries, you don't notice until something breaks in production. What Is a Prompt Canary? A prompt canary is a known-answer test that you run regularly against your AI workflow. If the canary fails, something in your pipeline has changed. It's the AI equivalent of a health check endpoint. Setting Up Canaries Step 1: Pick 3-5 Representative Tasks Choose tasks that cover your main use cases. Step 2: Define Pass/Fail Criteria Not "output match