Retrieval and grounding
The assembler checks access, revision and authority before using them together.
Links containing ?t= open the video at a specific second.
The ideas to retain
1. Retrieval is not context assembly
Let \(qt\) be a query derived from the current task. A system can generate candidates through several retrievers:
2. Lexical, semantic, and structured retrieval solve different problems
Semantic retrieval is useful when intent and vocabulary do not match literally. Lexical retrieval preserves signals an embedding may dilute: error codes, proper nouns, identifiers, exact…
3. Fusing rankings does not fuse meaning
Two retrievers may emit incompatible scores.
Jump directly to a section
Read the reviewed transcript
This video has no narration. This transcript reproduces its on-screen text; it does not invent a spoken track.
Three ways to find evidence
Exact search finds identifier ERR17. Semantic search finds its explanation.
A structured query returns the current operation state. These are different candidates.
The assembler checks access, revision and authority before using them together.
Scores do not share a scale
One list ranks A above B; another ranks B above A. Their scores use different scales.
Combining positions merges the lists without treating raw scores as probabilities.
The merged order does not prove that a source is current or authoritative.
Fresh index, old copy
The source changed from A to B. The index still contains A.
Indexing A ten seconds ago updates the index clock, not the document revision.
The check compares revisions and requires B when the decision needs current state.
Do not average contradictions
An old policy says thirty days and the current policy says fourteen. Both address the same rule.
Supersession determines which revision applies; the deadlines are not averaged.
Without authority to resolve another conflict, keep it unresolved and seek evidence.
A citation must support the claim
Policy e3 sets fourteen days and order e4 is twenty days old.
The ineligibility conclusion needs both sources, not just a URL at the end.
A claim of thirty days contradicts e3 even when it includes a citation.
Identify the failing layer
If B is missing from the candidates, retrieval failed.
If B is found but the assembler selects A, evidence admission failed.
If B enters but the answer repeats A, generation failed. The same wrong answer can have different causes.
