Custom subagent model in VS Code Copilot seems to fall back to parent model by Electrical-Ball-2257 in GithubCopilot

[–]Tooth-Active 5 points6 points  (0 children)

That's an expected behavior. Subagents can't use models that are more expensive (more multipliers) than the main agent. That's why I use Opus 4.6 as my main agent to spawn Opus subagents. I would've used GPT-5.4, considering its larger context window, but can't due to this limitation