How would you approach capturing and maintaining metadata about the data model — a business glossary or data dictionary?

The goal is an artefact that stays true, which rules out anything maintained by hand:

1. Use the platform's own metadata: Field Description and Help Text for business definitions, and the Data Classification attributes for ownership, usage, sensitivity, and compliance category. Populating these makes the org self-documenting.
2. Extract programmatically: Retrieve object and field metadata through the Metadata or Tooling API on a schedule and publish it as the dictionary. Because it is generated, it cannot drift from reality.
3. Detect drift: Diff successive extracts to surface new fields with no description, no owner, or no classification, and route those to the responsible team. This turns documentation from a project into a control.
4. Add what the platform cannot hold: Source-system lineage, transformation logic, and business rules typically live in the integration or warehouse layer, so the glossary needs to reference those rather than pretend Salesforce is the only source.
5. Enforce at the gate: Make description and classification mandatory in the change-control checklist for new fields. Retrofitting three hundred undocumented fields is a project; documenting each one at creation is a minute.