The suggested ones are terrible, and it's guidance is terrible.
Last weekend I ran head to head tests of agents against each other with a variety of ideas, and selected the best one, and did it again. It has caused me to have a very specific subagent system, and I have an agent who creates those.
Did you use the one suggested here https://docs.anthropic.com/en/docs/claude-code/sub-agents or have you created custom ones?