How I debug RAG failures with deterministic signals

When building LLM apps, one frustrating problem is that a response can be wrong for many different reasons. The model may have hallucinated. The retriever may have pulled the wrong chunks. The answer may not be grounded in the provided context. A tool call may be missing. A JSON schema may have failed. Or the prompt may simply be brittle. I started experimenting with a more structured way to debug these failures. Instead of only asking another LLM "is this answer good?", I wanted to compute s...