Allow the agent runner to take ChatInput

@Marcus can you suggest a good test to see if this interferes with anything? Code looks fine but I can't see what would use it when you approach through the UI.

Set to "needs work" at Marcus' request so a test can be identified and built into the testing suite.

Since this will not affect the current way of doing it and since we want to benchmark this for Drupal CMS - I will merge this for now.