5.4 — Codebase Exploration & Context Degradation

CCAR-F Domain 5 · Task 5.4

What You Need to Know

Context degradation = model loses grip on earlier specific findings (refers to "typical patterns" instead of class names). It is an attention quality problem, not a token-limit problem. Larger context windows do not fix it.

Primary Mitigations

1. Scratchpad files — write key findings outside conversation context; refer back later
2. Subagent delegation — isolate verbose exploration in separate contexts; coordinator keeps only summaries
3. Summary injection between phases — inject Phase 1 summary into Phase 2 subagent prompts (prevents cold start)
4. /compact — use proactively during extended sessions to protect context quality
5. Structured state manifests — for crash recovery; load on resume and inject into agent prompts

Key Concept: Context degradation is lost grip on specific findings, not a token limit problem. Scratchpad files keep findings outside the context. Subagents isolate verbose exploration. Manifests prevent lost progress.

Exam Traps

• Increasing the context window to solve degradation
• Expecting next-phase subagents to inherit phase-one history
• Restarting a session without saving state
• Using /compact only when hitting limits