For covering the risk of mistakes I suggest considering ways of "visually quoting" the documents.
If the summary says "closing timeline: X" but there's an icon I can click that pops open an overlay with a visual cropped screenshot of that part of the original PDF - maybe even with a red circle around that detail - I can trust those summaries a whole lot more.
Gemini 2.5 has image bounding box and masking features that can help with this (sadly missing from Gemini 3.)
If the summary says "closing timeline: X" but there's an icon I can click that pops open an overlay with a visual cropped screenshot of that part of the original PDF - maybe even with a red circle around that detail - I can trust those summaries a whole lot more.
Gemini 2.5 has image bounding box and masking features that can help with this (sadly missing from Gemini 3.)