Use when working on complex multi-step tasks, when a session is getting long (40+ tool calls), when the agent starts ignoring rules it followed earlier, when conventions drift, when output quality seems to degrade, or after any context compaction event. Prevents long-session corruption AND context c

Session Guard Overview Long sessions corrupt silently. Context compaction drops instructions unannounced. Hooks don't fix it (confirmed by multiple developers on GitHub issues 19471, 9796, 64171). This skill prevents both through behavioral self enforcement: monitor health, anchor critical rules through compaction, split before damage occurs. No packages, no databases pure behavioral enforcement that works in every harness. When to Use Session exceeds 40 tool calls Agent contradicts earlier decisions Style/naming conventions start drifting After any context compaction event Task scope growing unbounded Health Signals Signal Threshold Action Tool call count 40 YELLOW: checkpoint + recite critical rules Tool call count 60 RED: split or compact with anchor Agent contradicts earlier decision Any VERIFY: re read source of truth Style/naming drift Any RECITE: state the active rules aloud File read returns unexpected content Any RE READ: don't trust cached state Task scope growing unbounded Continuous SPLIT: one task per session Protocol Green Zone (0 40 tool calls) Normal operation. No intervention needed. Yellow Zone (40 60 tool calls) 1. CHECKPOINT summarize progress in one paragraph 2. RECITE state the 3 5 most critical active rules aloud: "Active rules: [naming convention], [file structure], [error handling pattern], [testing requirement]" 3. ASSESS almost done? Push through. Not done? Prepare split. 4. REDUCE no exploratory reads. Only targeted operations. Red Zone (60+ tool calls OR drift signal) 1. STOP do not make more tool calls 2. VERIFY re read project rules (don't trust memory) 3. CHECKPOINT write state to handoff document 4. SPLIT create handoff, suggest fresh session Context Anchoring (anti compaction) When compaction has occurred (sudden loss of earlier context, or after /compact): 1. RE READ the project's rules file immediately 2. RECITE the 3 5 critical rules aloud in your response 3. VERIFY your planned next action matches those rules before executing 4. If uncertain about ANY prior decision, RE READ the source file don't guess What survives compaction: Most recent user messages (high priority) Currently invoked skill body (capped at 5K tokens, oldest dropped first) Git status and project structure File contents read AFTER compaction What gets LOST in compaction: Decisions made early in conversation Architectural rules stated only verbally (not in files) Context from tool outputs (file reads, command outputs) Compaction Safe Pattern Keep critical instructions in FILES (CLAUDE.md, CONTEXT.md), NOT in conversation. If a rule matters, it must live in a file the agent can re read not in something agreed on earlier. Common Mistakes Trusting that you remember the rules after 50+ tool calls (you don't re read) Re reading EVERYTHING to be safe (wastes tool calls be targeted) Feeling fine therefore assuming context is fine (compaction is SILENT) Splitting AFTER noticing problems (split BEFORE prevention, not recovery) Why This Matters Context compaction is the 1 unsolved platform problem in 2026. Hooks don't fix it (confirmed: the agent ignores post compaction injections because the compaction summary creates narrative momentum). This skill is the lightweight behavioral countermeasure: no infrastructure, no packages disciplined self monitoring that works in every harness.

session-guard