Modifying system prompts changedagent-sdk/modifying-system-prompts
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109109An output style is a markdown file with [frontmatter](/docs/en/output-styles#frontmatter) for metadata, followed by the prompt content. Save it to `~/.claude/output-styles/` for a user-level style available in every project, or `.claude/output-styles/` in your repository for a project-level style you can commit and share with your team.
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111By default, a custom output style replaces the `claude_code` preset's software engineering instructions with your own. To keep them and layer your instructions on top, set `keep-coding-instructions: true` in the frontmatter. Keep them when your agent is still doing software engineering work. Leave them out when you're replacing the role entirely.
111A custom output style leaves the `claude_code` preset's software engineering instructions out and uses your own. To keep them and layer your instructions on top, set `keep-coding-instructions: true` in the frontmatter. Those instructions are only in Claude Code's full system prompt, so the setting has no effect in a session on the shorter system prompt, which you pin on or off with [`CLAUDE_CODE_SIMPLE_SYSTEM_PROMPT`](/docs/en/env-vars#variables). Keep them when your agent is still doing software engineering work. Leave them out when you're replacing the role entirely.
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113113The example below defines a code-review persona that keeps the coding instructions, since reviewing code still benefits from Claude Code's security and code-quality guidance. Save it as `~/.claude/output-styles/code-reviewer.md` to make it available across projects:
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