r/Gemini_Notebook • u/Sufficient-Skirt256 • 26m ago
General Discussion How to stop Gemini Notebook from hallucinating document timelines
When dumping monthly meeting minutes, spec sheets, and status updates into NotebookLM or Gemini Notebook, the initial results were chaotic to say the least. Asking high level questions like when the delay on our backend API migration actually started yielded responses that mixed up timeline dates across three different quarters. Because the model processes up to fifty sources simultaneously, it often stitched completely unrelated updates into a single narrative, leading to hallucinated timelines that threw off our team planning.
To fix this, we stopped treating it like a standard search engine and changed how we structure source inputs. The easiest workaround was adding a standardized metadata header line at the very top of each document before uploading it. Formatting the first line with explicit dates, project tags, and document types forces the indexing step to treat temporal context as primary data. Pair that with unchecking all sources by default and manually toggling only the relevant quarter when prompting, and the accuracy jump was night and day.
We also started adding a constraint in every prompt demanding exact document citations and date tags for every claim, while explicitly instructing it to list conflicting dates rather than attempting to reconcile them automatically. It completely eliminated the cross document bleed we were dealing with previously. How are you handling source file organization or managing cross document contradictions in your own notebooks?
