If a source, dataset, or decision question is missing, say so before drafting a confident conclusion. Name the missing item, why it matters, and who can supply it. Determine whether the summary can still answer a narrower question with the evidence already available.
If you proceed, mark the scope and assumptions prominently. For example, “This covers published sources through August; internal usage data was unavailable” tells readers how to interpret the result. Do not manufacture a placeholder citation or treat an absent source as evidence of absence. When the input arrives, revisit affected claims and document any change to the conclusion.
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