Some commands are manipulating Command as values e.g.: echo-dmr ls -l
The Command echo-dmr would need an API to:

• retrieve a populated command. Today this can (nearly) be done the following way:
  CommandContainer<Command> container = registry.getCommand(opName, originalInput);
  CommandLine line = container.getParser().parse(originalInput, false);
  line.getParser().getCommandPopulator().populateObject(line, commandInvocation.getInvocationProviders(), commandInvocation.getAeshContext(), true);
  Command c = line.getParser().getCommand();

You will notice that commandInvocation.getInvocationProviders() is not today exposed by the AeshConsole,

2 possible API:

• Simply expose the InvocationProviders in the AeshConsole.
• Or expose a new method Command getPopulatedCommand(String commandLine) in the CommandInvocation interface.

I would vote for the method that hides the detail of how the parsing is operated.