What a retrieval system actually stores

Documents before vectors

The useful object is the source document and the passage that was shown to a person. An embedding is an index. If you cannot open the passage, the answer is not reviewable.

Chunks are an editorial choice

Splitting a policy on every heading keeps a citation readable. Splitting on a fixed character count often cuts a rule in half. We write down the splitter.

Refusal is a feature

If no passage clears the threshold, the assistant should say it does not know. A fluent guess is a bug.

function answer(passages: Passage[]) {  if (passages.length === 0) return { refused: true, text: 'No approved source.' };  return { refused: false, text: draftFrom(passages), sources: passages };}