The useful starting point
Start with the question, then supply the material needed to answer it. Label sources, make essential constraints explicit, and inspect what the AI received when it misses something.
Separate instructions from reference material
Instructions describe the job. Reference material supplies information for that job. Label them separately so you can review both parts of your request.
For a document comparison, identify the versions, explain what counts as a meaningful change, and ask for evidence from both documents. Without a clear task, a large pile of text is still an ambiguous request.
Try a small, answerable question first
Before asking for a complete report, ask a question with an answer you can find in the source. This checks whether the relevant text is available and usable.
The example below is an editorial exercise. It tests source use, not general knowledge.
Using Document A and Document B below, compare the cancellation deadlines. Quote the relevant sentence from each and explain the difference. If either deadline is absent, say so. Document A — current version: [paste text] Document B — proposed version: [paste text]
Distinguish a missing source from a bad answer
If the answer fails, supply the exact relevant paragraph directly and retry the same question. If that works, investigate document extraction, retrieval or source selection before rewriting the whole prompt.
If it still fails, simplify the task and inspect the output against the paragraph. This control experiment narrows down the problem; it does not prove which component is responsible in every app.
Keep a compact working brief
For a long project, maintain a short brief with the goal, decisions, definitions, unresolved questions and source references. Review it yourself before using it in a fresh conversation.
A brief is a deliberate way to carry important information forward. It should not replace original documents when exact wording or complete evidence matters.
A small experiment
Choose a question about one document. Compare three inputs: the full document, only the relevant section, and a short summary you wrote. Check accuracy and evidence in each answer.