RAG loses a rule’s conditions or exceptions: how should chunks be repaired?

Locate the original limitation and the final generation context

This applies when “available only in selected versions” becomes availability in all versions, or a table loses a limiting footnote. Locate the source passage and save both retrieved candidates and the final model input. A correct document among candidates is insufficient if the generation context contains only its heading and main sentence.

Separate parsing omissions, chunk boundaries and later truncation

Check that the limiting sentence survives parsing, then inspect chunk boundaries and overlap. If the original chunk is complete, investigate reranking or truncation that retained only its first part. Hierarchical headings and lists also carry meaning. An isolated exception without its governing rule can be unusable; merely increasing character count does not establish repair.

Retrieve complete rules and exceptions along structural boundaries

Prefer paragraph and structural boundaries, fetch neighboring chunks where needed, and retain document and section identifiers. Inspect overlap for excessive duplication that crowds out other evidence. Change one strategy at a time on the same failed question and record the final context. Ask generation to preserve conditions explicitly rather than merely add a vague citation.

Verify conclusion scope rather than retrieved text volume

Test a rule and exception placed in adjacent paragraphs, checking each version and object limitation in the answer. Include normal rules without exceptions to ensure the change does not turn every answer into refusal. Success requires the relevant passage to be used and the conclusion’s scope to be correct, not simply more retrieved text or a higher similarity score.

No chunk length is best for every document. Tables and complex layouts may need parsing repairs first. This article ran no vector retrieval service and provides no measured performance improvement from chunk settings. If the platform hides actual model context, inspect public citations and source text but do not claim to identify exactly where a condition disappeared.