Per-session model switching without restarting

Problem

The /model command changes the model globally, affecting all open Claude Code terminals simultaneously. There's no way to run different models in different terminals without launching each one with --model.

If you're mid-conversation and want to switch one terminal to a different model (e.g., switch to Sonnet for a simpler task while keeping Opus in another terminal), the only workaround is:

1. /exit
2. claude --model claude-sonnet-4-6
3. /resume

This is disruptive and clunky.

Desired behavior

/model should change the model for the current session only, not globally. Each terminal session should maintain its own independent model selection, just like the --model launch flag does — but switchable mid-conversation without restarting.

Current workarounds

• Launch each terminal with --model flag upfront (requires knowing in advance)
• Exit, relaunch with new model, and /resume (loses flow, takes extra steps)