Why the First Turn in a Coding Agent Can Use So Many Input Tokens — and Why That Gets Better Over Time

Coding agents such as Cortex Code, Claude Code, Codex, and Cursor rely on large language models (LLMs) behind the scenes. A common question from users is: “Why does my first turn consume so many input tokens when I only typed a short prompt?” This post explains how prompt caching works in these systems, why the first turn often looks expensive, and why cache hit rates usually improve as a session continues. Key point : Coding agents like Cortex Code benefit from the same general prompt-caching p