coop-dax-review 0.6.1

Offline, advisory DAX/model standards linter for Power BI semantic models: parses TMDL/.bim, checks measures and model structure against the team's DAX standards, and reports anything that doesn't match. Human report + machine JSON for the company agent. Never edits or blocks.

coop-dax-review

Offline, advisory DAX/model standards linter for our Power BI semantic models. It parses TMDL (and legacy .bim) models, builds a model catalog, checks measures and model structure against docs/standards.md (our DAX standards + Microsoft/Tabular best practices), and surfaces anything that doesn't match. It never edits or blocks — it only reports. Human reports (a sectioned, colorized terminal report, Markdown, or a self-contained branded HTML file) and machine JSON for the company analytics agent.

Sibling tool to coop-sql-review — same architecture and contracts.

Install

pipx install coop-dax-review        # from PyPI

Use pipx, not system pip, so the tool stays isolated from other CLIs (ms-fabric-cli, azure-cli) it might otherwise fight over shared pins. For local development:

python -m venv .venv && .venv/bin/pip install -e ".[dev]"

Usage

coop-dax-review check [MODEL_PATHS...] [--format text|json|markdown|html] [-o FILE]
                      [--open/--no-open] [--color/--no-color] [--log-file FILE]
                      [--baseline FILE] [--write-baseline FILE]
                      [--min-severity error|warning|info] [--strict]
coop-dax-review rules                 # list every rule (id, severity, tier, agent?)
coop-dax-review upgrade               # show the command to update (never self-applies; alias: update)
coop-dax-review --version

• MODEL_PATHS point at a PBIP/TMDL model folder (*.SemanticModel/definition/...), any folder of .tmdl files, or a legacy .bim file. Directories are searched recursively; defaults to ..
• Run it with no paths in a terminal and it offers a checkbox picker of the subfolders to check (all selected by default — press ENTER to scan everything).
• Advisory: exit code is always 0. --strict is the opt-in CI gate — exit 2 when any finding remains at/above --min-severity.
• --standards <path> overrides the bundled standards (e.g. point it at a canonical company standards file). Its sha256 travels in the JSON so the agent knows which standards a report used.
• A rules.yml beside the standards file (or --config) can disable rules, override severities, and tune thresholds — all with no rebuild. For example, raise what counts as a "non-trivial" measure:

  rules:
    DAX-VAR-RETURN:
      params: { min_functions: 5 }   # also: DAX-COMPLEX-NO-HEADER.min_vars,
                                      # DAX-DISPLAY-FOLDERS.min_measures, DAX-SIMPLE-FUNCTIONS.min_calculates
  

coop-dax-review check ./MyModel.SemanticModel
coop-dax-review check . --format json --strict --min-severity warning
coop-dax-review check . --format html              # writes a report file and opens it in your browser
coop-dax-review check . --format markdown -o report.md

The default --format text is a sectioned terminal report: a banner, one section per model with ERROR/WARN/INFO severity badges, and a SUMMARY panel. It's colorized automatically when you're at a terminal and falls back to plain text when piped or redirected (override with --color/--no-color; NO_COLOR is respected).

--format html produces a self-contained, branded HTML report (inline CSS + embedded logo, no network). It is always written to a file — coop-dax-review-report.html by default, or wherever -o points — and the path is printed and opened in your browser (pass --no-open to skip the open, e.g. in CI). upgrade/update print the exact command to run yourself (pipx upgrade coop-dax-review, etc.) rather than self-applying, since a package manager can't replace the tool while it is running.

What it checks

Run coop-dax-review rules for the live list. Deterministic rules (reported as findings):

Rule	§	Sev	Flags
DAX-MEASURE-CATEGORY	1	warning	measure not named [Category: Name]
DAX-MEASURE-NOT-PREFIXED	1	warning	Table[X] where X is a measure (measures take no prefix)
DAX-COLUMN-PREFIXED	1	warning	bare [X] where X is a column (columns need Table[X])
DAX-VAR-RETURN	2	info	non-trivial measure with no VAR/RETURN structure
DAX-NO-NESTED-CALCULATE	3	warning	CALCULATE nested inside CALCULATE
DAX-FILTER-TABLE-IN-CALCULATE	4	warning	FILTER(<table>, <col> = ...) where a plain column filter suffices
DAX-SNOWFLAKE	6	info	a table with relationships chained through it (snowflake link)
DAX-BIDI-RELATIONSHIP	7	warning	a bidirectional cross-filter relationship
DAX-MARKED-DATE-TABLE	8	warning	time-intelligence used but no marked Date table
DAX-MEASURE-IN-ITERATOR	9	info	a measure referenced inside a row iterator (hidden context transition)
DAX-COMPLEX-NO-HEADER	12	info	a complex measure (≥3 VARs) without a /* ... */ header
DAX-DIRECTLAKE-NO-CALC-COL	13	warning	a calculated column in a Direct Lake model
DAX-USE-DIVIDE	14	warning	the / operator where DIVIDE() should be used
DAX-FORMAT-STRING	15	warning	a measure with no explicit formatString
DAX-NO-FLOAT-KEYS	16	info	a relationship key column typed double
DAX-HIDE-FK-COLUMNS	17	info	a visible foreign-key (relationship) column
DAX-KEY-SUMMARIZEBY-NONE	18	info	a numeric key column that auto-aggregates (summarizeBy ≠ none)
DAX-DISPLAY-FOLDERS	19	info	a measure-heavy table with no display folders

Agent-judgment rules — the tool detects the construct but emits to the JSON agent_review list (never an auto-finding), because the call needs intent the linter can't infer:

Rule	§	Judges
DAX-KEEPFILTERS-NEEDED	5	whether a CALCULATE boolean filter needs KEEPFILTERS
DAX-STAR-SCHEMA	6	whether a snowflake chain should be flattened to a star
DAX-CONTEXT-TRANSITION	9	whether an iterator's context transition is intended/correct
DAX-SIMPLE-FUNCTIONS	10	whether a CALCULATE-heavy measure could use simpler functions
DAX-VALIDATION	11	whether the §11 validation checklist was run for a non-trivial measure
DAX-IMPLICIT-MEASURE	20	whether a visible auto-aggregating numeric column should become an explicit measure

See RULES.md for the full taxonomy. docs/standards.md §14–§20 are adopted Microsoft/Tabular best practices (DIVIDE, format strings, key column types, hidden FKs, key summarizeBy, display folders, explicit measures); docs/standards-proposed-additions.md is the original candidate list.

Suppressing findings (adopting on an existing model)

Two deterministic, never-blocking ways to silence findings you've already triaged:

• Inline — drop a comment on a finding's line (or the line directly above it):

  // coop-dax-review:ignore DAX-VAR-RETURN reason: legacy measure, rewrite scheduled
  

  List several rule ids (ignore DAX-A, DAX-B), or use a bare ignore / * to silence every rule on that line. The reason: text is for humans; it's ignored by the parser.
• Baseline (ratchet) — record today's findings and surface only new ones going forward:

  coop-dax-review check . --write-baseline dax-baseline.json   # once, to capture the status quo
  coop-dax-review check . --baseline dax-baseline.json         # thereafter: only new findings appear
  

  Each finding has a stable, line-independent fingerprint (in the JSON), and the baseline is a sorted list of those. A baseline entry that no longer matches any finding (you fixed it) is reported as a diagnostic so the file self-cleans (--write-baseline to prune).

Agent JSON contract

{
  "tool": "coop-dax-review", "schema_version": 1, "version": "x.y.z",
  "standards": {"path": "...", "sha256": "..."},
  "models_checked": 2,
  "verdict": {"clean": false, "highest_severity": "warning"},
  "findings": [{"rule_id":"...","severity":"warning","model":"Sales","file":"...","line":12,
                "object":"[Sales: Revenue YTD]","message":"...","standard_ref":"§3","fingerprint":"4ad6aeb79867"}],
  "summary": {"error":0,"warning":2,"info":4},
  "agent_review": [{"rule_id":"...","model":"Sales","file":"...","line":40,"object":"[...]","note":"...","standard_ref":"§5","fingerprint":"..."}],
  "diagnostics": [{"severity":"warning","category":"parse_failed","file":"...","message":"..."}]
}

schema_version lets a consumer pin the shape; verdict/models_checked give a quick machine verdict + coverage signal; each finding's fingerprint is a stable id for tracking across runs.

Project docs

• SPEC.md — architecture, CLI, agent contract, milestones.
• RULES.md — every standard mapped to a concrete check (deterministic vs agent-judgment).
• docs/standards.md — the canonical DAX standards the linter checks against (bundled as package data).
• CLAUDE.md — orientation for Claude Code sessions in this repo.