Process Studio and Object Studio Development
Two studios, two purposes
Process Studio builds the main flow and uses Action stages to call Business Objects. Object Studio builds the application-specific layer and exposes Actions (public methods) and Functions (internal helpers). A candidate must be fluent in the stage palette of both, including how links, decision expressions, and stage properties differ.
Expressions and calculations
Understand Blue Prism expression syntax: string concatenation with &, comparison operators, AND/OR/NOT, and functions such as Len(), Left(), Right(), Mid(), InStr(), Replace(), Trim(), MakeDate(), FormatDate(), AddDays(), and ToNumber(). Know that a Calculation stage assigns to a data item on its Outputs tab, and that a Decision stage evaluates a single boolean expression on its outgoing links.
Object Studio specifics
Know the Application Modeller: application types, launch and attach behaviour, and element attributes with match modes (Equal, Wildcard, RegEx, NotEqual, Contains, StartsWith). Understand the difference between Wait stages, Read stages (which output to data items), Write stages (which set values), Navigate stages, Code stages, and Action stages that call other objects.
Traps to watch for
Questions frequently probe the difference between a Decision and a Choice stage, the fact that a Read stage must have an output data item, that element attributes should be chosen for stability rather than convenience, and that spy modes (Win32, Accessibility, UIA, Browser, Region) suit different technologies. Another trap: assuming a Navigate stage can both navigate and read.
Rule of thumb
Match on the most stable attribute available - typically an ID or name rather than screen coordinates or dynamic text - and add a second attribute only if it genuinely increases uniqueness.