The Merriam-Webster dictionary gives as the meaning of scope as a verb to look at for evaluation, as in "to scope out the competition." But that's not how we use it at Microsoft.
Here are some fake citations:
The Widgets pop-up shows the available widgets scoped to the current selection.
The results of the search are scoped to the current folder.
Workflows can be scoped to containers, content types (scopeable to containers, sites, collections, servers, or enterprises), or combinations of these.
Okay, that last one wasn't fake. You can tell it's not fake because it is extra confusing.
To be scoped to something is to be limited to or filtered to that thing, or things which apply to that thing. In other words limited in scope to. Here's an attempt to translate those citations into English:
The Widgets pop-up shows the available widgets which apply to the current selection.
The results of the search are filtered to those in the current folder.
I'm not going to try to translate that last one on there. It has this sort of Escherian feeling to it. "Workflows can be scoped to A, or to B (which can be scoped to A), or combinations of A and B (which means combinations of A, and B, and A's within B's?)"
Another sense of the verb phase scoped to is altered in scope. Usually, the change is to reduce the scope to meet external constraints:
The proposal has been scoped to meet our December release.
To emphasize that the scope has been narrowed, you add the adverb down: "scoped down to."
Translation: "The original proposal was too broad and could not be accomplished within the required time allotted, so we reduced its scope to the point where the parts that remain can be accomplished in time."
On the other hand, sometimes scope expands.
Based on customer feedback, the search results have been scoped to include archived data as well.
And finally, a citation from an official Microsoft job description:
Oversees the structuring of consulting engagements to ensure they are properly scoped to meet the customer's requirements profitably.