The service "plugin.manager.ai_agents" has a dependency on a non-existent service "plugin.manager.ai.function_calls

Please update the steps to reproduce once identified.

I believe you might need to update the AI core version. I was having a similar issue on drupal/ai:1.0.3. I've updated it to 1.1.3 and now it works as expected.

This one should not be possible at all anymore unless you fetch directly from Git - we require 1.1.x in the composer. Will close.