[BUG] When the yellow text "Approaching Opus usage limit · /model to use best available model" is displayed, running "/model opus" and entering a prompt will automatically revert to Sonnet

Environment

• Platform (select one):
• [x] Anthropic API
• [ ] AWS Bedrock
• [ ] Google Vertex AI
• [ ] Other: <!-- specify -->
• Claude CLI version: 1.0.56 (Claude Code)
• Operating System: WSL Ubuntu 22.04
• Terminal: Bash

Bug Description

<!-- A clear and concise description of the bug -->

Steps to Reproduce

1. With /model selection in its default state, use the Opus model until the message "Approaching Opus usage limit · /model to use best available model" appears.
2. Execute the "/model opus" command to force the use of Opus.

Expected Behavior

<!-- What you expected to happen -->
The Opus model should be enforced to be used until the Usage Limit is reached.

Actual Behavior

<!-- What actually happened -->

> /model opus
  ⎿  Set model to opus (claude-opus-4-20250514)

> /model
  ⎿  Set model to opus (claude-opus-4-20250514)

> /init is analyzing your codebase…

● I'll analyze the codebase and create a comprehensive CLAUDE.md file for this Discord Event
  Notifier project.

● Read(README.md)
  ⎿  Read 134 lines (ctrl+r to expand)

Claude Opus 4 limit reached, now using Sonnet 4

● Read(CLAUDE.md)
  ⎿  Error: File does not exist.

● List(.)
  ⎿  Listed 184 paths (ctrl+r to expand)

Additional Context

There may be additional conditions required for situational reproduction, such as auto-compact occurring.