[FEATURE] Pre-compaction checkpoint dialog

[cjbrigato]

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

During long agentic sessions, Claude Code's context compaction triggers silently and drops information unpredictably.

I was implementing a Logs tab feature for my embedded toolkit - JSON endpoint, parsing, display, filtering. Mid-task, compaction happened. The agent delivered a working feature - impressive given what it retained - but the filtering functionality got lost.

The problem: I had zero visibility into what was about to be dropped, and no opportunity to say "filtering is the critical part, prioritize that." The agent performed perfectly within its constraints, but I only discovered the gap when the task was "done."

This makes long-context agentic work feel like a gamble rather than a collaboration.

Proposed Solution

Before compaction, show an interactive checkpoint prompt:

⚠️ Context reaching capacity. Compaction needed.

I plan to retain:
- Log tab basic implementation ✓
- JSON endpoint structure ✓

Likely to lose detail on:
- Filtering feature
- Auto-refresh polling

What's critical to preserve? [user input]

This lets the user make an informed tradeoff. If something's missing afterward, it's a decision they made, not a silent loss they discover later.

Alternative Solutions

Current workarounds:

• Overstuffing CLAUDE.md with context (pollutes every session)
• Manually re-explaining lost context after compaction (wastes tokens, breaks flow)
• Keeping sessions artificially short (defeats the purpose of agentic work)
• Accepting the loss and fixing gaps manually (current reality)

None of these address the core issue: lack of user agency in the compaction decision.

Priority

High - Significant impact on productivity

Feature Category

Interactive mode (TUI)

Use Case Example

1. Working on ESP32 embedded project with custom logging system
2. Ask Claude Code to implement a Logs tab in my dev toolkit
3. Task involves: firmware-side JSON endpoint, Go API bridge, frontend tab with display + filtering
4. Context fills up mid-implementation
5. WITH THIS FEATURE: Claude shows me it's about to drop "filtering" details, I say "keep filtering, drop the API bridge details, I can re-explain that part"
6. Compaction happens with my priorities preserved
7. Feature ships complete, no silent gaps

Additional Context

This transforms compaction from "silent information loss" into "tactical retreat you authorized."

The current experience feels like a soldier dying mid-mission - you only find out when objectives aren't fully met. The proposed UX makes it a conscious tradeoff.

-- Cordially compacted