r/ClaudeAI: Bad MCP Tool Design Shown to Cost Agents 5× More Tokens — Identical Functionality, Vastly Different Efficiency

A developer on r/ClaudeAI published a comparative test on June 3 showing that two MCPs implementing identical functionality produced up to a 5× difference in token consumption and context window usage. The analysis pinpoints schema verbosity, excessive tool descriptions, and poor response chunking as the primary culprits. The post documents specific before/after patterns and is drawing significant traction among developers tuning agent costs.