Universal Claude.md – cut Claude output tokens by 63%
One file. Drop it in your project. Cuts Claude output verbosity by ~63%. No code changes required. Note: most Claude costs come from input tokens, not output. This file targets output behavior - sycophancy, verbosity, formatting noise. It won't fix your biggest bill but it will fix your most annoying responses. Model support: benchmarks were run on Claude only. The rules are model-agnostic and should work on any model that reads context - but results on local models like llama.cpp, Mistral, or others are untested. Community results welcome.
When you use Claude Code, every word Claude generates costs tokens. Most people never control how Claude responds - they just get whatever the model decides to output.
All of this wastes tokens. None of it adds value.
Drop CLAUDE.md into your project root. Claude Code reads it automatically. Behavior changes immediately.
The honest trade-off: The CLAUDE.md file itself consumes input tokens on every message. The savings come from reduced output tokens. The net is only positive when output volume is high enough to offset the persistent input cost. At low usage it costs more than it saves.
Same 5 prompts. Run without CLAUDE.md (baseline) then with CLAUDE.md (optimized).