Semantic search finds similar text, and it will happily find similar text from the wrong place. A version, a language, a product, or an access rule is a filter applied before or after the search, and forgetting one is how a system answers about the wrong thing.
About 1 min of reading
Before this new lesson, one small question about the lesson you just finished. Recall it, do not look it up.
Filter then rank.
Tag the chunks
Before you run it, say out loud what it will print. Then open the answer.
Prove the empty case
Before you run it, say out loud what it will print. Then open the answer.
Before you write anything, put these lines back in the right order. Click a line to move it up one step. This support step is easier than writing code from scratch, and it is here to make the last example stick.
Read the first example one line at a time. A line that prints shows what appears on screen; the rest set things up quietly.
A filter that leaves nothing should say so rather than answer from an unfiltered fallback. A fallback that ignores the filter is the bug that turns a wrong answer into a plausible one.
If the question names a version or a product, that has to become a filter. Extracting it is a small step, and skipping it is why a system answers about the default version every time.
Restrict the candidates to the allowed set, then rank inside it. Filtering after ranking can return fewer results than you asked for, and a short list is how a system silently stops answering.
Store the version, the section, and the source with each chunk. Every answer then carries what it was about, and a question about a specific version has something to match against.
A user who cannot see a document must not get a chunk from it in a prompt. The permission check belongs in the retrieval step, because that is the only place the candidate set exists.
Each one is defined here on this site. Open the entry for the full definition and the other words it points at.