Are you positive that Copilot is calling that tool at all? Copilot picks what tools it uses based on the tool's description. You can't simply tell copilot that it's there and be guaranteed it's really going to use it. It's more likely to acknowledge the tool's existence in the way you're seeing.

Try describing it like, "Call every time the user says the word 'hello' in order to retrieve the desired response." Or anything else that's going to give Copilot incentive to actually execute the command. You can also look at the descriptions of any of the other tools you have loaded and model yours after them.