[FEATURE] Cowork: give users a manual /compact (user-initiated compaction)

Environment

• Claude Desktop 1.10628.0 (Windows 11 x64, MSIX)
• Bundled Claude Code 2.1.160
• Cowork mode

Problem

In Cowork, context compaction is automatic only. The user has no way to trigger it deliberately — no /compact command, no button. Auto-compact fires at times the user cannot predict or control, including mid-task, and the user can only watch it happen.

Why user-initiated compaction matters

My intended workflow, which is impossible today:

1. At a natural breakpoint, ask the agent to write a handoff document summarizing state, decisions and next steps.
2. Manually trigger compaction at that exact moment, while the handoff doc safely exists as a file.
3. Feed the handoff doc back in — same conversation, no information lost, no need to start a new conversation.

This is exactly how experienced users manage long sessions in the Claude Code CLI with /compact. In Cowork the same user has zero agency: compaction lands wherever the auto-trigger decides, sometimes in the middle of a multi-step task, and the agent comes back confused about what it was doing.

Expected behavior

A user-facing way to trigger compaction on demand — a /compact command, a button next to the context meter, either is fine. Ideally accepting optional focus instructions like the CLI's /compact <instructions>.

Related issues

• #24677 (compaction death spiral in Cowork) — user-initiated compaction at a clean breakpoint would also be a practical mitigation for pathological auto-compact behavior.
• #57773 (user-configurable autocompact threshold) — same underlying theme: users want agency over when compaction happens.