# Structured Output Pitfalls: JSON Mode Token Greed and the Real Cost of Tool-Use Forcing

> Source: https://sukruyusufkaya.com/en/learn/token-ekonomisi/structured-output-json-mode-tool-use-cost
> Updated: 2026-05-14T14:44:13.029Z
> Category: Token Ekonomisi & LLM Cost Optimization
> Module: Module 5: The Cost Dimension of Prompt Engineering
**TLDR:** Using JSON mode doesn't mean 'fewer tokens' — in most cases it uses **more tokens**. Schema complexity, field name length, escape characters — all hidden token costs. This lesson covers cost-aware structured output design.