HOW TO SCOPE A CUSTOM BLUEPRINT AUDITOR.

Question 1: What does "audit" actually mean here?

Almost everyone uses the word "audit" differently. Pinning it down is the single most useful hour you'll spend before scoping. The four common interpretations:

• Conformity check — does the drawing match the spec book section it references?
• Code check — does the drawing comply with the applicable building code?
• Constructability review — can the trade actually build what's drawn given site realities?
• Coordination check — do the architectural, structural, and mech drawings agree at intersections?

These are four different products. A constructability reviewer needs trade-by-trade rules of thumb; a code checker needs the local code as a structured input. Pick one to start.

Question 2: What inputs are actually available?

Drawings come in many shapes: vector PDFs, raster scans of marked-up plots, native DWG, Revit models. Each one needs different ingest. A pipeline that works on clean vector PDFs falls over on a 600-DPI scan with handwritten markup.

Make a list of the last ten projects' drawing-set formats. Be honest about which ones are messy. The auditor's accuracy will be capped by the worst-format set you need it to handle.

Question 3: Who acts on the output?

This sounds obvious until you realize different consumers want very different things:

A PE wants a ranked punch list of issues with one-sentence summaries and links to the affected drawing region.

An estimator wants the issues categorized by trade and quantity-of-impact.

An owner's rep wants a formal report with the methodology footnoted, suitable for sharing with the design team.

Same underlying analysis; three different outputs. Pick the primary user and design backwards from their workflow.

Question 4: What does "good enough" look like?

The honest acceptance criterion for v1 isn't "catches everything a senior PE would catch." That's an unfair bar — most senior PEs disagree with each other. The real bar is:

• Catches 80% of issues a competent PE would catch.
• False-positive rate low enough that the PE still trusts the output after a week.
• Saves enough time per drawing review that the PE prefers the assisted workflow over the manual one.

Define those numbers before you start. They become the test set.

The three artifacts you need before code

Before any modeling work begins, three artifacts should exist:

1. A test set of 20-30 real drawings with a senior PE's annotations of what they consider issues. This is what you measure against.
2. A one-page output spec showing the exact format the auditor's report will take. Stakeholders sign off on this before you start.
3. A one-page rules document describing the categories of issue you want flagged and any explicit exclusions.

Skipping any of these three is the most common failure mode. The model is the easy part. The scoping is what kills projects.

A 14-day build plan that actually works

Once those four questions are answered:

• Days 1-3: ingest pipeline for your drawing format, baseline retrieval against the spec book.
• Days 4-7: first-pass auditor running against your test set; iterate on prompts and rules.
• Days 8-11: output formatter, integrations into wherever the PE works (Bluebeam, Procore, email).
• Days 12-14: measurement against acceptance criteria, runbook handover, training.

That's the cadence. It works because the hard work happened before day 1.