With regard to the advantages and disadvantages associated with the use of coaching-specific AI agents and non-coaching-specific chatbots for and in coaching, the following presents a concept that seeks to combine the respective advantages while avoiding the respective disadvantages. This is the concept of triadic AI coaching with coaching-diagnostic knowledge and an external AI prompt script, which provides coaches with prompts that help them, together with their coachees, to develop prompts that they then submit to a ready-to-use AI agent for processing. The key feature of this concept is to largely dispense with internal AI prompt scripts and to place process control entirely in the hands of the coaches and their coachees. They are supported, on the one hand, by an external AI prompt script that links coach prompts with AI prompts, and on the other hand, by an AI agent that has access to coaching-diagnostic knowledge and uses this to provide suggestions for analyzing the present coaching issue and developing suitable solution proposals.