The bid was already on the street when the architect emailed a new set. The estimator opened a chatbot, uploaded the old PDF, then the new one, and asked what had changed. It took several prompts to get past the sheets the model preferred to talk about. One of the changes was a curb, and the bid did not include it.
Scope that moves without a meeting
Revision churn between the bid set and the permit set is where scope moves without a meeting. A ten-day tender leaves no time to overlay every sheet by eye. The miss surfaces later as a change order.
A general contractor that has been pointing language models at live Procore jobs built a narrow tool for this task. It pulls sheets from structured drawing records, so the revision history it reads is the actual history. The model reads both versions. Each finding is pinned to a location on the sheet, and the run is saved for the next review.
Whether the curb belongs in the number is a person's call.
Tim Fairley publishes construction skills for Claude, and in August 2026 a GC mapped his eight strongest onto a live Procore app. Drawing compare was already in the app. Button-press quantity takeoff was not. Fairley sets that boundary himself: counting tagged fixtures on a vector PDF can work; measuring areas and lengths usually does not. Count fixtures, and every checked sheet goes onto a coverage list.
Revision compare divides the same way. The software holds the two sets still, and the model describes what moved between them.