Universal CLAUDE.md reduces Claude output tokens by 63% in benchmarks

A developer has released a universal CLAUDE.md file that significantly reduces token usage in Claude responses while maintaining technical accuracy. The tool was built entirely with Claude's assistance during a single session where Claude researched Reddit threads, GitHub issues, and prompt engineering research.

What it fixes

• "You're absolutely right!" and "Great question!" on every response
• "I hope this helps! Let me know if you need anything!" closings
• Em dashes, smart quotes, Unicode chars that silently break parsers
• Restating your question before answering it
• Unsolicited suggestions and over-engineered code
• "As an AI..." framing
• Hallucination guard - if you correct Claude on something, it treats that as ground truth for the rest of the session and never re-asserts the wrong answer

Benchmark results

The developer tested the same 5 prompts with and without the file:

• Explain async/await: 180 words → 65 words (64% reduction)
• Code review: 120 words → 30 words (75% reduction)
• What is REST API: 110 words → 55 words (50% reduction)
• Hallucination test: 55 words → 20 words (64% reduction)
• Total: 465 words → 170 words (63% reduction)

The developer notes that answers maintain the same technical accuracy - just without the fluff.

Implementation and profiles

The solution requires just one file dropped in your project root with no code changes. It includes three profiles for different use cases:

• CLAUDE.coding.md - for dev projects and code review
• CLAUDE.agents.md - for automation pipelines and bots
• CLAUDE.analysis.md - for data and research work

The tool is built on real GitHub issues (including #3382 with 350+ upvotes) and community research. The repository is open to PRs and profile contributions, with the developer encouraging users to open issues for any annoying behaviors they want fixed.