Gemini Q&A

Use Google’s Gemini CLI to answer questions about the codebase.

Prerequisites

Gemini CLI must be installed:

npm install -g @anthropic-ai/gemini-cli
# or follow installation at https://github.com/google-gemini/gemini-cli

Authentication must be configured (Google API key or Application Default Credentials).

Usage

Spawn the gemini-qa subagent to handle the question:

Use the Task tool to spawn the gemini-qa agent with the user's question.

The subagent will:

1. Formulate a clear prompt for Gemini
2. Run gemini -p "question" in headless mode
3. Return Gemini’s response

Direct Usage (without subagent)

If you prefer to run Gemini directly:

gemini -p "your question here"
# or
gemini "your question here"

Command Options

• Basic query: gemini -p "question"
• Positional: gemini "question"
• Pipe input: cat file.txt | gemini -p "summarize this"
• JSON output: gemini -p "question" --output-format json
• File reference: gemini -p "@src/file.ts explain this"

File References with @

Gemini supports @ syntax to include file context:

# Reference a specific file
gemini -p "@src/auth.ts Explain this module"

# Reference a directory
gemini -p "@src/ Summarize all code here"

Common Use Cases

• Code explanation: “What does this function do?”
• Architecture questions: “How is the database layer structured?”
• Finding patterns: “Where is error handling implemented?”
• Code review: “Review this file for potential issues”
• Comparison: Get a second opinion on a code question

Notes

• Use -p flag for headless (non-interactive) mode
• Gemini is git-aware and respects .gitignore for directory references
• For complex questions, use the subagent for better context isolation