How to Leverage Gemini CLI's 1M Token Context Window

# Include entire project
gemini -p "@./ Give me an overview of this entire project"

# Include specific directories
gemini -p "@src/ @lib/ Explain the architecture of this codebase"

# Include specific files
gemini -p "@src/main.js @config/settings.json How does the configuration flow work?"

# Use the --all_files flag for complete inclusion
gemini --all_files -p "Analyze the project structure and dependencies"

# Include additional directories in the workspace
gemini --include-directories ./frontend,./backend,./shared

# Or specify multiple times
gemini --include-directories ./frontend --include-directories ./backend

gemini -p "@src/ @lib/ Explain the architecture of this codebase.
Identify the main components, their responsibilities, and how they interact."

gemini -p "@src/ @middleware/ Has dark mode been implemented?
Show me the relevant files and functions."

gemini -p "@src/ @api/ Is JWT authentication implemented?
List all auth-related endpoints and middleware."

gemini -p "@package.json @src/ Identify all external dependencies
and explain how each is used in the codebase."

# Generate OpenAPI specification
result=$(cat api/routes.js | gemini -p "Generate OpenAPI spec for these routes" --output-format json)
echo "$result" | jq -r '.response' > openapi.json

# Generate README from codebase
gemini -p "@src/ @package.json Generate a comprehensive README.md
with installation instructions, usage examples, and API reference" > README.md

gemini -p "@./ Create an architecture document that includes:
1. System overview diagram (as Mermaid)
2. Component descriptions
3. Data flow explanations
4. Technology stack summary" --output-format json > architecture.json

#!/bin/bash
for dir in src/*/; do
    component=$(basename "$dir")
    gemini -p "@$dir Document this component with:
    - Purpose and responsibilities
    - Public API
    - Dependencies
    - Usage examples" > "docs/${component}.md"
done

Get-ChildItem -Path "src" -Directory | ForEach-Object {
    $component = $_.Name
    gemini -p "@src/$component Document this component" | Out-File "docs\$component.md"
}

# Get high-level understanding
gemini -p "@./ Analyze this legacy codebase:
1. What language(s) and frameworks are used?
2. What is the apparent architecture pattern?
3. What are the main entry points?
4. Are there obvious technical debt indicators?"

gemini -p "@src/ Map the dependencies between modules.
Identify tightly coupled components that may need refactoring.
Present as a dependency graph in Mermaid format."

gemini -p "@src/ @tests/ Identify and explain the core business logic.
Use the tests to understand intended behavior where code comments are lacking."

gemini -p "@src/ This is a legacy Express.js application.
Create a detailed migration plan to convert it to FastAPI, including:
1. File-by-file migration strategy
2. API endpoint mapping
3. Authentication migration approach
4. Database access layer changes"

gemini -p "@src/ Refactor the authentication module to use modern async/await
patterns while maintaining backward compatibility with existing callers."

# Pipe file content
cat README.md | gemini --prompt "Summarize this documentation"

# Pipe command output
git log --oneline -50 | gemini -p "Summarize recent changes and identify major features"

# Pipe multiple files
cat src/*.js | gemini -p "Review this code for security vulnerabilities"

# Save to text file
gemini -p "Explain Docker" > docker-explanation.txt

# Output as JSON for programmatic processing
gemini -p "List all functions in @src/" --output-format json > functions.json

# Append to existing documentation
gemini -p "@src/newfeature.js Document this new feature" >> CHANGELOG.md

# Analyze application logs
tail -10000 /var/log/app.log | gemini -p "Identify error patterns and suggest fixes"

# Process database query logs
cat slow-queries.log | gemini -p "Analyze these slow queries and suggest optimizations"

# Project Context for Gemini CLI

## General Instructions
- Follow existing coding style (2-space indentation, single quotes)
- All new functions must have JSDoc comments
- Prefer functional programming patterns

## Project Structure
- /src contains application code
- /lib contains shared utilities
- /tests contains Jest test files

## Coding Standards
- Use TypeScript strict mode
- Prefix interfaces with `I` (e.g., `IUserService`)
- Use async/await instead of callbacks

/compress

{
  "compressionThreshold": 0.6
}

/memory add "The main database connection is in lib/db.ts and uses connection pooling"

/memory show    # View loaded context
/stats          # View token usage and caching stats

/clear          # Wipe context and start fresh

# Install via npm (recommended)
npm install -g @anthropic-ai/gemini-cli

# Or use Homebrew
brew install gemini-cli

# Shell integration for zsh (default on modern macOS)
echo 'eval "$(gemini --shell-init zsh)"' >> ~/.zshrc

# Grant terminal full disk access for analyzing system directories
# System Preferences > Privacy & Security > Full Disk Access > Terminal

# Install via npm
npm install -g @anthropic-ai/gemini-cli

# PowerShell integration
Add-Content $PROFILE 'Invoke-Expression (gemini --shell-init powershell)'

# For Git Bash
echo 'eval "$(gemini --shell-init bash)"' >> ~/.bashrc

# Path handling - use forward slashes or escape backslashes
gemini -p "@src/utils/ Analyze these utilities"        # Works
gemini -p "@src\\utils\\ Analyze these utilities"       # Also works

# Install via npm
npm install -g @anthropic-ai/gemini-cli

# Shell integration (bash)
echo 'eval "$(gemini --shell-init bash)"' >> ~/.bashrc

# Shell integration (zsh)
echo 'eval "$(gemini --shell-init zsh)"' >> ~/.zshrc

# For restricted environments, ensure /tmp is accessible
# or set a custom temp directory
export TMPDIR=/path/to/writable/temp

# Check caching stats
/stats

# Dependencies
node_modules/
vendor/

# Build output
dist/
build/
.next/

# IDE files
.idea/
.vscode/

# Large binary files
*.zip
*.tar.gz
*.mp4

# Generated files
coverage/
*.log

# Use Gemini for exploration (free tier), Claude for implementation
gemini -p "@src/ Explain the authentication flow"
# Then use Claude Code for actual code changes

# GitHub Actions example
- name: Generate Release Notes
  run: |
    git log --oneline $(git describe --tags --abbrev=0)..HEAD | \
    gemini -p "Generate release notes from these commits" > RELEASE_NOTES.md

# Review a pull request
git diff main...feature-branch | gemini -p "Review this diff for:
1. Potential bugs
2. Security issues
3. Performance concerns
4. Code style violations"