Your Agent's Tool Descriptions Are Costing You 66% Accuracy

Project Toolmetry showed that rewriting MCP server tool descriptions via LLM improves agent success: SQLite from 34% to 100%, Memory from 61.8% to 96.4%, Git from 75% to 96.7%. The model and code were unchanged; the entire experiment cost $4 in API expenses.

• SQLite: success rate rose from 34% to 100% after description edits
• Memory: growth from 61.8% to 96.4%, Git from 75% to 96.7%
• All changes were only text descriptions; model unchanged
• Entire experiment cost $4 in API expenses