The definition
Retrieval-augmented generation means the system retrieves relevant documents first, then generates an answer grounded in what it retrieved, rather than answering purely from what the model absorbed in training.
It is why modern AI answers can cite current sources and why they can change as sources change.
Why it matters for visibility
If answers are generated from retrieved documents, then being retrievable is the precondition for being included. That is a different problem from ranking: being accessible, parseable and clearly relevant to the query at retrieval time.
It also explains the instability: a small change in what gets retrieved can change the answer, which is why single runs are unreliable and repeat sampling is necessary.
The practical implication
Answer-first formatting, clean extractable statements, accurate structured data, and presence on the third-party sources that get retrieved alongside yours.
Check it yourself
Ask an assistant a question about your category and look at which sources it cites. Those are the documents that were retrieved.
That citation list is a target list, and it tells you where the answer about your category is actually being written.
See where you actually stand
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