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System Prompts – Claude API Docs

The page provides release notes and documentation for system prompts used with Claude API, detailing updates, changes, and best practices for effectively configuring system prompts to guide model behavior across different use cases.

Background

- Anthropic is the AI company behind Claude, a large language model (LLM) similar to OpenAI's ChatGPT or Google's Gemini. - A "system prompt" is a set of hidden instructions given to an AI model before a conversation starts, shaping its behavior, tone, and constraints. Unlike user messages, the user may not see it. - This page is part of Anthropic's official developer documentation for the Claude API, meaning it's written for engineers building applications on top of Claude. - Anthropic has published the actual system prompts it uses inside Claude (e.g., for the claude.ai web product), making them transparent. This is noteworthy because most AI companies keep such prompts proprietary. - The release notes track changes over time to these prompts, showing how Anthropic tunes Claude's personality, safety rules, and formatting instructions in production.

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