The  Context Setup menu allows the creation of Context Variables for use with Activator Slots and Combo SequencesContext Variables are used for conditions that the Activator Slots and Combo Sequences must meet to allow response from the events. This, in turn, opens up unlimited possibilities of combos. For e.g. having combos that can only be performed when the player character is flying, which are different to when the character is standing or different combos based on the type of weapon being used. These examples are just the tip of what you can create with the use of Context Variables.

1. Context Variable Types
This is the popup to select from the type of Context Variable to add. The types include String, Int, Float, Bool and Parameter.

2. Debug Mode
This is used to get information feedback from the GAC System. It provides multiple types of information:

Animation Info: logs when an animation has been linked in a combo.
Hit Info: logs when a hit is detected from an animation.
Hit Range Info: logs when object is within hit range of the closest attack
Target Info: logs when the object is added as a target to the Target Tracker when within range
Input Info: logs what inputs are used
Context Info: logs when a context variable value is updated

3. Context Filter
This is used to filter out the types of variables to show to reduce clutter in the Inspector.
 
4. Context Slots
All Context Slots share these same attributes:
Context Name : The custom name of the Context Variable Slot
Comparison: The comparison popup to choose from includes Greater Than, Less Than, Equal and Not Equal
Condition Value: The condition value to meet for the Context Variable Slot

String Context
Uses the strings for values. Only comparisons to choose from are Equal and Not Equal

Int Context
Uses whole numbers int for values. Comparisons to choose from are Greater Than, Less Than, Equal, Not Equal

Float Context
Uses floating point for values. Comparisons to choose from are Greater Than, Less Than, Equal, Not Equal

Bool Context
Uses booleans for values; allows for selection between True or False. Only comparison available is Equal

Parameter Context
Uses Animator Controller Parameters for values; allows for selection of the Parameters being used in the Mecanim Animator. Comparisons are based on the type of Parameter being used and adjusts the selections accordingly.
 
See the UpdateContext() API on the       GAC API Reference       page for examples on how to use Context Variables.
GAC API Reference