Move 4: Retrieve context

Retrieval means pulling information into the context dynamically, when it is needed, rather than keeping it there permanently. RAG is the classic example. The agentic-search approach above (using grep and glob over the filesystem) is another form of retrieval. The key idea shared across these articles is that retrieval should be on-demand: bring the information in for the step that needs it, then let it leave again, rather than letting everything accumulate.

There is one important warning attached to retrieval, from Part 2: do not use RAG to manage your tool definitions. Fetching tool definitions dynamically each step based on similarity tends to fail, because it creates a shifting context that breaks the KV cache and confuses the model (a tool that was present in turn 1 disappears in turn 2, and the model may "hallucinate" it back). Tools should stay stable.