Context Degradation Monitor

Detects context window degradation and prescribes corrective actions before accuracy drops.

Severity Zones

Zone	Token Range	Status	Action
Green	< 32K	Healthy	Normal operation
Yellow	32K - 64K	Caution	Begin selective compression
Orange	64K - 100K	Warning	Compress aggressively; summarize completed phases
Red	100K - 140K	Danger	Spawn fresh subagent for remaining work; pass only essential context
Critical	> 140K	Severe	Halt complex reasoning; compress immediately; do not attempt multi-step tasks

Reference: Models advertise 200K but reliability drops past 32K. "Lost in the middle" effect: middle tokens have 20-40% lower recall past 100K.

Early Warning Indicators

Symptoms that context degradation is affecting output quality (regardless of token count):

1. Repeated tool calls — Agent re-reads files already read in same session
2. Contradictory reasoning — Later steps contradict earlier decisions
3. Missing prior context — Agent "forgets" task scope or constraints stated at session start
4. Over-explanation — Agent re-explains concepts already established
5. Stale references — Agent references file paths or task IDs that were resolved earlier

If 2+ indicators are present, treat as one zone higher than token count suggests.

Corrective Routing by Zone

Yellow (32-64K):

• Invoke Skill({ skill: 'token-saver-context-compression' }) at the current phase boundary
• Remove completed phase content from active context
• Keep: current task spec, key decisions, in-progress file list

Orange (64-100K):

• Invoke Skill({ skill: 'context-compressor' }) — aggressive summarization
• Write phase summary to .claude/context/tmp/phase-summary-{date}.md
• Prune: all resolved task details, intermediate research, superseded plans

Red (100-140K):

• Do NOT continue complex multi-step tasks in current agent
• Spawn a fresh subagent with only the compressed summary as context
• Current agent: write handoff doc → call TaskUpdate(completed) with handoff path in metadata

Critical (>140K):

• Halt immediately
• Write emergency summary: what was done, what remains, key decisions
• Route to session-handoff skill
• Invoke Skill({ skill: 'session-handoff' }) before context window forces truncation

Detection Checklist (Run at Each Phase Boundary)

[ ] Token count below 32K? → Green, no action
[ ] Token count 32-64K? → Yellow, begin compression
[ ] Token count 64-100K? → Orange, compress aggressively
[ ] Token count 100K+? → Red/Critical, spawn fresh agent
[ ] 2+ early warning indicators? → Upgrade one severity zone
[ ] Compression reminder file exists? → Invoke context-compressor immediately

Integration

• Pairs with: context-compressor, token-saver-context-compression, session-handoff
• Called by: planner (at plan start), developer (after each phase), router (before large spawns)
• Trigger: Check at every phase boundary, not just when problems appear

Iron Laws

1. ALWAYS check token count at every phase boundary — not just when problems appear or after completing a large task.
2. NEVER continue complex multi-step tasks past 100K tokens in the same agent context — spawn a fresh subagent with a compressed handoff instead.
3. ALWAYS treat 2+ early warning indicators as one severity zone higher than the raw token count suggests.
4. ALWAYS invoke token-saver-context-compression at Yellow zone (32–64K) before context bloat becomes severe — prevention is cheaper than recovery.
5. NEVER claim a task complete without writing a context summary when operating in Red or Critical zone — if it's not written down, the next agent won't know it happened.

Anti-Patterns

Anti-Pattern	Why It Fails	Correct Approach
Waiting until output quality degrades before checking context	By the time quality drops, the context is already in Red/Critical zone	Run detection checklist at every phase boundary proactively
Continuing multi-step tasks past 100K tokens	"Lost in the middle" effect causes 20–40% recall drop; decisions made early are forgotten	Spawn fresh subagent at 100K with compressed context summary
Ignoring early warning indicators because token count looks fine	Indicators are more reliable than raw token counts; a 30K session with 3 indicators is already Yellow	Treat 2+ indicators as one zone higher regardless of token count
Spawning a subagent without a written handoff document	Subagent starts from scratch, duplicating work or missing constraints	Always write phase summary to .claude/context/tmp/ before spawning
Compressing context by deleting tool call results without summarizing	Compression without summarization loses critical findings from earlier phases	Summarize completed phase outputs before pruning raw tool results

Memory Protocol (MANDATORY)

Before starting: Read .claude/context/memory/learnings.md

After completing:

• New pattern -> .claude/context/memory/learnings.md
• Issue found -> .claude/context/memory/issues.md
• Decision made -> .claude/context/memory/decisions.md

ASSUME INTERRUPTION: If it's not in memory, it didn't happen.