Compact Discoveries

Condense old discoveries into concise summaries and manage file size.

Compact old discoveries into a condensed summary and trim the active file.

Use the Task tool to delegate this work to a subagent with model: sonnet and subagent_type: general-purpose. Pass the following prompt to the subagent:

You are working in a cs session. Your task is to summarize old discoveries and trim the active file to stay within its size budget.

Steps

  1. Check if compaction is needed:

    • Read .cs/discoveries.md
    • Measure the file size with wc -c
    • Get the budget: ${CS_DISCOVERIES_MAX_SIZE:-60000} bytes (default 60KB, override via env var)
    • If the file is under the budget, report that there's nothing to compact and stop

  2. Read the full discoveries.md and identify all ## entries

  3. Decide what to keep vs compact:

    • The most recent entries (roughly the last half of the budget) stay in discoveries.md untouched
    • Older entries get summarized into .cs/discoveries.compact.md

  4. Produce a condensed summary of the older entries with these rules:

    • Each original ## entry becomes 1-3 bullet points capturing the key technical finding
    • Merge entries that cover the same topic into a single section
    • Drop entries that were superseded or corrected by later entries
    • Preserve actionable information: file paths, command patterns, configuration values, workarounds
    • Drop exploratory dead-ends unless they contain useful "don't do this" warnings

  5. Update .cs/discoveries.compact.md using this format:

# Compacted Discoveries

> Condensed summary of older findings. See discoveries.md for recent entries.

## [Topic or Finding Title]
- [Key point 1]
- [Key point 2 if needed]

## [Next Topic]
- [Key point]

If discoveries.compact.md already exists, merge the new compacted entries into it (don't duplicate existing sections — update them if the new entries add information).

  1. Trim discoveries.md:

    • Keep the # Discoveries & Notes header
    • Keep only the recent entries (the ones NOT compacted)
    • Write the trimmed file back

  2. Report back:

    • How many entries were compacted vs kept
    • The size reduction (before vs after in characters)

Important

  • Read the ENTIRE discoveries.md before writing — context from later entries may supersede earlier ones
  • Split on ## heading boundaries — never break an entry mid-section
  • Favor precision over brevity: a specific file path or command is more useful than a vague description