[FEATURE]: Collapsible reasoning summaries

[dbpolito]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

Add collapsible UI for reasoning summary parts, matching the existing "Explored" pattern. Shows "Reasoning" with shimmer animation while the model is thinking, then transitions to "Reasoning Summary" as a collapsible section (open by default) when complete.

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• Agent responses need collapsable button #14405: Agent responses need collapsable button (requests collapsible UI for thinking/reasoning content)
• [FEATURE]: Hide thinking blocks with configuration toggle #10470: [FEATURE]: Hide thinking blocks with configuration toggle (related feature for controlling reasoning block visibility)

If your request is distinct, please clarify how it differs from the above.

[epicwhale]

+1 to having collapsed thinking, as currently when showing thinking is enabled, the TUI conversation feels rather noisy, and hard to visually ingest.... compared to Claude Code and Codex in comparison.

[yourjhay]

+1 This is very useful feature if ever. Making opencode TUI more clean.

[skaldebane]

Can affirm the same. I almost always want to see the reasoning as the model does it (particularly for open-weight models which show the actual full reasoning), so sometimes it's easier to stop it and steer if it goes too deep the wrong road or gets fixated on something that's not consequential to my request (e.g. random errors or warning that aren't relevant to the task).

I think the best implementation would be to automatically expand the "current" reasoning block, and automatically collapse it once it moves to the next reasoning block (or finishes the actual final response), with the ability to expand any past reasoning block.