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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Commands
+- **Run Bot**: `python bot.py`
+- **Lint**: `ruff check --fix .` or `ruff format .`
+- **Run Tests**: `python -m unittest discover -v`
+- **Run Single Test**: `python -m unittest src/plugins/message/test.py`
+
+## Code Style
+- **Formatting**: Line length 120 chars, use double quotes for strings
+- **Imports**: Group standard library, external packages, then internal imports
+- **Naming**: snake_case for functions/variables, PascalCase for classes
+- **Error Handling**: Use try/except blocks with specific exceptions
+- **Types**: Use type hints where possible
+- **Docstrings**: Document classes and complex functions
+- **Linting**: Follow ruff rules (E, F, B) with ignores E711, E501
+
+When making changes, run `ruff check --fix .` to ensure code follows style guidelines. The codebase uses Ruff for linting and formatting.
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