power-bi-model-review

name	power-bi-model-review
description	Use this skill whenever the user shares a Power BI or Analysis Services semantic model (a TMDL export, a BIM/JSON model definition, or a pasted list of tables, relationships, and measures) and asks for a model review, a performance check, or help fixing DAX, before writing or correcting any DAX measure for that model.

Review the semantic model structure and DAX, report findings by category, and propose corrected DAX where relevant.

Instructions

1. Get the model definition. Accept a TMDL folder/export, a .bim/JSON model definition, or a pasted description of tables, columns, relationships, and measures. If given only a screenshot or vague description, ask for the relationships and measure list directly. A review needs the actual expressions, not a summary of them.

2. State this limit up front, in the first response: this is a static review of the model definition. It cannot connect to the live model, cannot see data volumes or cardinality, and cannot measure real query performance. Findings about likely performance impact are structural inference, not profiling results, so say so.

3. Check the model against each category below. Skip a category cleanly if the model doesn't contain what it checks (e.g. no bi-directional relationships to review).

4. Report findings grouped by category, worst-impact first:

   Category	Object	Issue	Fix
   Relationships	Sales to Customer	Bi-directional, both dimension tables	Set to single-direction; use CROSSFILTER(..., BOTH) inside the one measure that needs it

   For any DAX fix, show the corrected expression in full, not a diff.

5. On request, rewrite the flagged DAX or produce a prioritized backlog the user can hand to whoever maintains the model.