Precision & Grounding
The Failure-Mode Catalog
10 min+90 XPStep 1/10
Every RAG failure has a stage address
The catalog, by pipeline stage:
- Retrieval miss — the right chunk exists but wasn't fetched (vocabulary mismatch, chunk boundary split the answer, index gap)
- Rerank drop — fetched, then scored out of the context by the second stage
- Context burial — in the context, ignored: middle position, crowded by distractors
- Generation error — faithful retrieval, unfaithful answer
- Stale index — the doc changed, the index didn't
- Injection — retrieved content carrying instructions the model obeys
Each stage has different fixes and different owners. 'RAG is bad' is not a diagnosis; 'the chunk dies at rerank on Tuesday queries' is.