skill-registry-system-reminders-burn-20k-tokens-per-tool-call
When the skill registry grows large (~170 skills), each tool call injects the full skill list as a system reminder consuming approximately 20k context tokens per return. This creates compounding context explosion in long multi-stage sessions and forced premature session stops. Mitigation: batch operations via scripts rather than iterative tool calls; use parallel subagents for large-volume work when write permissions allow; plan stage boundaries to fit within one session before token pressure builds.