# Prune Context > Selectively prune redundant lines from .agent/FULL_CONTEXT.md via AI (Gemini/Codex). Use when FULL_CONTEXT.md has grown large (500+ lines). Distinct from /compact (Claude Code built-in, which summarizes the live conversation). Use when this capability is needed. - Skill: `tomevault-io/prune-context` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/prune-context` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/prune-context/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/prune-context --- # Prune FULL_CONTEXT.md (selective line removal) > **Not to be confused with `/compact`.** `/compact` is Claude Code's built-in conversation summarizer. `/prune-context` removes redundant lines from the durable `.agent/FULL_CONTEXT.md` log. See the "Which compaction do I need?" table in `CLAUDE.md`. Use Gemini (or the standard fallback chain) to surgically remove redundant lines from `.agent/FULL_CONTEXT.md` while preserving all important context. ## Prerequisites - At least one backend must be available. Try in order: Gemini MCP → `$GEMINI_API_KEY` curl → Codex MCP → Claude subagent (last resort) - FULL_CONTEXT.md should be large enough to warrant compaction (500+ lines) - The Claude subagent has a 200K token window — for very large logs, it may need to process in chunks ## Steps 1. **Check size.** Read `.agent/FULL_CONTEXT.md` and count lines. If under 500 lines, tell the user it's not worth compacting yet and stop. 2. **Archive the original.** Copy the current file: ``` cp .agent/FULL_CONTEXT.md .agent/LOGS/FULL_CONTEXT.pre-compact.md ``` 3. **Send to the backend** (using the standard fallback chain) with this prompt: > Read this entire context log. Identify lines that are redundant, superseded by later entries, or no longer relevant. > > Output ONLY the line numbers to remove, grouped by reason. > > **Preserve:** all decisions, all open task references, all lessons learned, all architectural context. > **Remove:** duplicate status updates, resolved issue descriptions, stale progress notes. 4. **Remove only the identified lines.** Use the Edit tool to remove each group of lines the backend identified. Work in reverse order (highest line numbers first) to avoid offset drift. 5. **Append a compaction note** at the end of FULL_CONTEXT.md: ``` --- Compacted on YYYY-MM-DD: removed N lines (Gemini-selected) --- ``` 6. **Report results** to the user: how many lines before, how many removed, how many remain. ## Rules - This is a **rare operation**. Most projects will never need it. - NEVER compact without an AI backend — human judgment is too lossy. Use the standard fallback chain. - NEVER delete the archive until the user confirms the compaction looks good. - If in doubt about whether to remove a line, keep it. --- > Source: [poma-ai/megavibe](https://github.com/poma-ai/megavibe) — distributed by [TomeVault](https://tomevault.io).