Sync Descriptions
In a SQL Server relational database, you can add descriptions to tables and columns using extended properties. Commonly, the MS_Description extended property is used, but other extended properties can be used. If you have spent considerable time entering descriptions for relational tables and columns, BIDS Helper Sync Descriptions can help you import those descriptions to the dimension in Analysis Services.
Select one or more dimensions then right click and choose Sync Descriptions...

Then a window pops up showing you all the extended properties in the relational database. Choose the extended property used as the description. Then choose any additional columns that you would like to show in the dimension attributes.

Let's say you have a column with the MS_Description property set to "The geographic region of the country" and the "Example Values" property set to "North, East, South, West". The description property for the corresponding attribute in Analysis Services will be set to:
_The geographic region of the country
Example Values: North, East, South, West_
Descriptions are applied to the dimension itself and to attributes within that dimension. Descriptions will be applied to any attribute with a NameColumn or with only one KeyColumn.
Limitations:
- Your dimension must be tied to a table or view in the DSV, not to a named query in the DSV.
- Only SQL Server relational databases are supported.
- Currently, the sync only works in one direction. You can only sync relational database descriptions into Analysis Services.
- Currently, Sync Descriptions only operates on Analysis Services dimensions, not measure groups.