I am working on a domain specific agent that includes the concept of skills. I only allow one to be active at a time to reduce the chances for conflicting instructions. I use a small sub-agent to select/maintain/change the active skill at the start of each turn. It uses a small fast model to match the recent conversation to a skill (or none). I tried other approaches, but for my use case this was worked well.

My model for skills is similar to this, but I extended it to have explicit use when and don’t use when examples and counter examples. This helped the small model which tended to not get the nuances of a free form text description.

You should consider calling these "behaviors" to mimic behavior trees in game / robot AI. They follow the same notion of a single behavior being active at once: https://en.wikipedia.org/wiki/Behavior_tree_(artificial_inte...