About this skill

The Problem

Engineering drawings and quantity takeoff checklists are often maintained by different people at different stages. A DWG may show a construction method, material, or quantity that does not match the xlsx, csv, or pdf checklist. Manual review requires extracting drawing text, aligning column names, and deciding whether a difference is just wording or a real issue, such as “120 pieces” versus “115 pieces,” C30 versus C25, or bored pile versus vibro-replacement pile.

How It Works

The skill organizes the review into a reproducible pipeline. It uses LibreDWG’s dwgread to extract text from TEXT, MTEXT, ATTDEF, and INSERT entities, then stores the result in dwg_text.json. The checklist parser supports .xlsx, .csv, and .pdf, and maps common column names such as item name, method, quantity, unit, and specification to standard fields. The core comparison is performed semantically by an LLM across six checks: term consistency, numeric consistency, material consistency, method consistency, missing-item check, and extra-item check.
Outputs include dwg_text.json, checklist.json, diff_result.json, plus dwg-diff-report.md and dwg-diff-report.html. The HTML report provides color-coded severity, collapsible item details, and print-friendly styling. Each step supports resumable execution, so existing outputs can be reused or regenerated.

Limits and Caveats

This is best used as an initial drawing-to-checklist consistency check, not as a formal engineering review. Users should confirm column mappings before comparison, because incorrect mappings can invalidate the result. Numeric values must use consistent units, such as m versus mm. Older LibreDWG versions may require text-mode output, and large DWG files can extract slowly. Drawing text may be spread across model and layout spaces, so incomplete extraction can limit coverage. Specialized domain terms may still be misinterpreted, so critical differences should be reviewed manually.

Screenshots

Use Cases

During bid review, compare DWG construction drawings with xlsx checklists to find method or material naming mismatches.
During quantity review, compare quantities and specifications in a PDF checklist with DWG annotations to flag missing or extra items.
Before handover, generate an HTML difference report that explains numeric and method conflicts between drawings and checklists.
When parsing csv checklists, confirm column mappings, then review terms, quantities, and materials dimension by dimension.

Best For

Bid technical leads who need to check DWG drawings against checklists for method and material differences before review.
Quantity surveyors who need to verify quantities, units, and material specifications for consistency.
Site engineers who need to turn drawing-to-checklist differences into handover or corrective materials.
BIM document engineers who need DWG text extraction and checklist parsing exported into reviewable reports.