- Command Dictionary:
  - Every option tree must include a dictionary named commands.cnf in its cfg subdirectory.
  - The dictionary specifies the following attributes for each command provided by the option tree:
    - Command name, including optional abbreviation point
    - Type of command (intrinsic, primitive, or macro)
    - Number of command parameters
    - Parameter names (optional)
    - Parameter default values (optional)
- Example Command Dictionary Entry:
  - A command definition entry occupies a single line in the dictionary and looks like this:

        MYC*OMMAND P, 3+, INPUT=, ITERATIONS=1K, 0

  - This fictitious entry demonstrates all of the commonly encountered variations:
    - The full command name is MYCOMMAND, which can be shortened to MYC. (You cannot give multiple commands in one option tree the same full or abbreviated command name, but identically named commands in different option trees is acceptable.)
    - The command is a primitive.
    - The command accepts 3 or more parameters.
    - The first parameter is named INPUT and has no default value.
    - The second parameter is named ITERATIONS and has a default value of 1024. NeXtMidas recognizes the 'K' and 'M' suffixes and assigns to them their customary binary values.
    - The third parameter is not named, but 0 is its default value.
    - All other parameters are neither named nor defaulted.