[Bug] Effort level change via /effort command affects all active sessions globally

[brentguistwite]

Summary

/effort level changes in one Claude Code session unexpectedly propagate to all other active sessions when using Opus 4.7. Effort appears to be stored/read globally rather than per-session.

Environment

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.119
• Feedback ID: fce0a0ea-346a-437b-8e7f-b28c6274c359
• Model: Opus 4.7 (claude-opus-4-7)
• Multiple concurrent Claude Code sessions in separate terminal windows

Steps to Reproduce

1. Open Terminal A, start new Claude Code session with Opus 4.7
2. Run /effort xhigh in Terminal A
3. Begin working on a prompt in Terminal A (long-running task)
4. Open Terminal B with a separate Claude Code session (also Opus 4.7)
5. Observe: Terminal B's ongoing task is now running at xhigh effort
6. In Terminal B, run /effort high
7. Switch back to Terminal A

Expected Behavior

Each session maintains its own independent effort level. Changing /effort in one session should not affect any other session.

Actual Behavior

Terminal A's effort level has changed to high, matching the value set in Terminal B. Effort level is shared across all active sessions instead of being session-scoped.

Impact

• Cannot run concurrent sessions at different effort levels
• A background long-running task can have its effort silently changed mid-run by activity in another window
• No warning or indication that the change is global

[github-actions]

Found 3 possible duplicate issues:

1. [BUG] /effort is global across concurrent sessions instead of session-scoped #49166
2. [BUG] Per-session isolation for effort level and model selection #51383
3. [FEATURE] /effort should be per-session, not global — breaks parallel workflows #42673

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🤖 Generated with Claude Code

[github-actions]

This issue has been automatically closed as a duplicate of #49166.

If this is incorrect, please re-open this issue or create a new one.

🤖 Generated with Claude Code

[github-actions]

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.