Tool Use

• Use ast-grep or sg for code structural search, lint or rewriting, cheatsheet: @~/.claude/ast-grep-rule.md
• Only use rg for recursive search, manual or automatic filtering of plain text output
• Use gemini to prompt for more understanding in large documents, images, or directory of files

Guidelines

• Use 4-space indentation, unless project or editor settings is configured otherwise
• Be precise and targeted in examining where changes need to be made
• Avoid inline styles, create separate CSS files
• Avoid creating a large file, split it into reusable modules
• Refactor long functions into smaller, reusable functions
• Follow development guidelines for files written in:
  • python: @~/.claude/python-guidelines.md
  • javascript / typescript: @~/.claude/typescript-guide.md
  • swift: @~/.claude/modern-swift.md

Available Tools

gemini-cli

gemini is available to prompt for more understanding

To prompt a text with gemini

echo "Explain the functions on @path/to/source_file.rs, and what do they achieve" | gemini

gemini -p "Explain the functions on @path/to/source_file.rs, and what do they achieve"

gemini -p "Analyze this document @path/to/document"

ast-grep

ast-grep or sg is available as CLI tool for code structural search, lint, and rewriting

ast-grep has following form

sg --pattern 'var code = $PATTERN' --rewrite 'let code = new $PATTERN' --lang ts

ripgrep

ripgrep is a command line tool that searches your files for patterns that you give it. ripgrep behaves as if reading each file line by line.

How to find all function definitions whose name is write:

$ rg 'fn write\('
src/printer.rs
469:    fn write(&mut self, buf: &[u8]) {

Xcode

• Use xcbeautify to pipe the output of xcodebuild

set -o pipefail && xcodebuild [flags] | xcbeautify

• List available simulators before running xcodebuild on a simulator

xcrun simctl list

• Run build for iOS simulator target, where -destination argument is set to a device such as name=iPhone 16, -scheme argument value is one from the list given by xcodebuild -list, use Debug configuration before building with Release configuration. Use available build configurations from the output. $PROJECT_NAME should be the name of the Xcode project in the current working directory

set -o pipefail && xcodebuild -workspace $PROJECT_NAME.xcodeproj/project.xcworkspace -configuration Debug -scheme $SCHEME -sdk iphonesimulator -destination "platform=iOS Simulator,name=iPhone 16" | xcbeautify

• Run test for iOS simulator target, where -destination argument value must be a concrete device given by name=iPhone 16. A Swift package typically have -Package suffix, resulting in $SCHEME-Package as a -scheme argument value

xcodebuild -configuration Debug -scheme $SCHEME-Package -sdk iphonesimulator -destination "platform=iOS Simulator,name=iPhone 16" test | xcbeautify

• Run test for macOS target, where -destination argument value must be a concrete device given by name=My Mac. A Swift package typically have -Package suffix, resulting in $SCHEME-Package as a -scheme argument value

xcodebuild -configuration Debug -scheme $SCHEME-Package -destination "platform=macOS,name=My Mac" test | xcbeautify