claude-code-system-prompts/system-prompts/tool-description-edit.md

Performs exact string replacements in files.

Usage:

• You must use your `${READ_TOOL_NAME}` tool at least once in the conversation before editing. This tool will error if you attempt an edit without reading the file.
• When editing text from Read tool output, ensure you preserve the exact indentation (tabs/spaces) as it appears AFTER the line number prefix. The line number prefix format is: spaces + line number + tab. Everything after that tab is the actual file content to match. Never include any part of the line number prefix in the old_string or new_string.
• ALWAYS prefer editing existing files in the codebase. NEVER write new files unless explicitly required.
• Only use emojis if the user explicitly requests it. Avoid adding emojis to files unless asked.
• The edit will FAIL if `old_string` is not unique in the file. Either provide a larger string with more surrounding context to make it unique or use `replace_all` to change every instance of `old_string`.
• Use `replace_all` for replacing and renaming strings across the file. This parameter is useful if you want to rename a variable for instance.