RAG vs CAG
Retrieval finds text. CAG prepares project knowledge.
Retrieval Augmented Generation is useful when the problem is finding relevant text. Software engineering often needs more: architecture, conventions, dependencies, impact paths, and constraints.
| Aspect | RAG | CAG |
|---|---|---|
| Primary question | Which files look relevant? | What does the model need to know about this project? |
| Context | Retrieved chunks | Computed project intelligence |
| Architecture | Search and prompt assembly | Project graph, learned representations, and task tools |
| Failure mode | Wrong or incomplete retrieved files | Incomplete project model or missing analysis signal |
| Best use | General knowledge lookup | Project-aware coding, review, impact, and architecture work |