CLAUDE.md vs System Prompt: What Actually Controls Claude Behavior
Dev.to AI
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Generative AI
CLAUDE.md vs System Prompt: What Actually Controls Claude Behavior You set up a system prompt. You write a CLAUDE.md file. They say different things. Which one wins? This is the most common confusion I see from developers using Claude Code. The system prompt and CLAUDE.md serve different purposes, operate at different levels, and have different enforcement characteristics. Understanding the difference is the key to getting consistent, predictable behavior from Claude.