That is a direct copy of what you would see in the action list. You can use the compound condition builder to create more complex statements like that.
You can also edit existing single conditions with the condition builder by right-clicking them in the action list, and choosing "Edit With Condition Builder".
The square brackets are visual markup added for the action list, they are not part of the action's input in this case. E.G. the first section is a text comparison where "{CMD}" is placed into the "Variable Name / Token" field
Square brackets in the action list usually denote input in a field that takes variable names, whereas single quotes denote input in a field that takes literal text (and usually tokens, which are the equivalent of literal text, after parsing).
Square brackets are not part of the token syntax, which uses curly braces to wrap each token.
They are, however, used for dynamic command sections, dynamic responses for text-to-speech, and special key indicators.