Computer Use: auto-compact or image size management needed for sustained GUI testing

Problem

When using Claude Code CLI's built-in Computer Use for GUI testing, the session quickly becomes blocked by the error:

"An image in the conversation exceeds the dimension limit for many-image requests (2000px). Run /compact to remove old images from context, or start a new session."

Every Computer Use action captures a screenshot, and after several steps the accumulated images trigger the multi-image dimension limit (2000px per image when 2+ images exist in context).

Why This Is a Problem

• No self-recovery: The agent cannot invoke /compact programmatically — it's a user-input-only CLI command. Once the limit is hit, the session is stuck.
• No setting to control screenshot resolution: Claude Code's built-in Computer Use doesn't expose a configuration option to reduce capture resolution below 2000px.
• Breaks autonomous workflows: If you delegate a Computer Use GUI test to a sub-agent (e.g., haiku), it cannot recover on its own and the task fails silently.

Expected Behavior

Computer Use sessions should be able to run for extended periods without manual intervention. Possible solutions:

1. Auto-compact old screenshots: Automatically remove or compress older screenshots from context when approaching the image limit.
2. Configurable screenshot resolution: Allow users to set a max resolution for Computer Use screenshots (e.g., --computer-use-resolution 1500).
3. Allow programmatic /compact: Let agents or hooks trigger /compact so automated sessions can self-manage.
4. Smarter image retention: Keep only the N most recent screenshots in context, discarding older ones automatically.

Steps to Reproduce

1. Start a Claude Code session
2. Request a Computer Use GUI test task (e.g., "test this Flutter app on the emulator using Computer Use")
3. After ~5-10 screenshot captures, the session is blocked with the dimension limit error
4. No way to recover without manual /compact or starting a new session

Environment

• Claude Code CLI (latest)
• macOS Darwin 25.3.0 (ARM64)
• Computer Use beta feature