Modes and Restrictions (Full vs Read-only vs Browse-only)
Organizations can run MCP Engine in different modes. Mode controls what tools are exposed and what information is intentionally suppressed.
What each mode means for your daily work
Full mode - you can do everything
In full mode, the assistant can read your model, run queries, and make changes on your behalf. This is the mode for active development work.
Practically, you can:
- Create and edit measures, tables, relationships, and roles - the assistant writes DAX, modifies schema, and applies changes directly.
- Run validation queries - execute DAX against live data to verify totals, test RLS behavior, or analyze performance.
- Refresh data - trigger model, table, or partition processing.
- Set up governance - configure preferences, policy rules, and unit tests.
Read-only mode - you can explore and validate, but not edit
In read-only mode, the assistant can see everything and run queries, but cannot change the model. This is common in production or shared environments.
Practically, you can:
- Browse the full model - tables, columns, measures, relationships, roles, expressions.
- Run DAX queries - validate totals, test RLS, analyze performance.
- Get an edit plan - the assistant proposes exact changes (object names, DAX expressions) that you apply manually in Desktop or Tabular Editor.
What you cannot do: create/update/delete measures, tables, relationships, roles, or any model objects.
Browse-only mode - you can discover and document, but not query or edit
Browse-only mode is the most restricted. It is designed for safe discovery in regulated environments where even query results could leak sensitive data.
Practically, you can:
- List tables, columns, measures, relationships, and roles - get oriented on model structure.
- Search by name and description - find objects related to a business term.
- Generate documentation - produce model overviews, naming inventories, and relationship maps.
What you cannot do: run DAX queries, see row-level data, view DAX/M expression content, refresh data, or make any edits. Expression details are intentionally suppressed.
If you're unsure which mode you're in, ask:
"What mode is this server in (full/read-only/browse-only), and what does that block here?"When something is missing
If the assistant says it cannot do something, the cause is usually one of four things:
- Mode - your organization restricted the server to read-only or browse-only.
- Tier - the feature requires Pro or Enterprise (e.g. dependency analysis, model history, unit tests, audit).
- Policy - a governance rule blocks or requires confirmation for that operation.
- Deployment settings - for example, XMLA connectivity is disabled for this environment.
Fast troubleshooting prompt:
"Is this blocked by mode, tier, policy, or deployment settings? What's the closest allowed alternative?"