/gemini_cli_skill

name: gemini-cli
description: Wield Google's Gemini CLI as a powerful auxiliary tool for code generation, review, analysis, and web research. Use when tasks benefit from a second AI perspective, current web information via Google Search, codebase architecture analysis, or parallel code generation. Also use when user explicitly requests Gemini operations.
allowed-tools:
  - Bash
  - Read
  - Write
  - Grep
  - Glob

Gemini CLI Integration Skill

This skill enables Claude Code to effectively orchestrate Gemini CLI (v0.16.0+) with Gemini 3 Pro for code generation, review, analysis, and specialized tasks.

When to Use This Skill

Ideal Use Cases

1. **Second Opinion / Cross-Validation**

• Code review after writing code (different AI perspective)
• Security audit with alternative analysis
• Finding bugs Claude might have missed

2. **Google Search Grounding**

• Questions requiring current internet information
• Latest library versions, API changes, documentation updates
• Current events or recent releases

3. **Codebase Architecture Analysis**

• Use Gemini's `codebase_investigator` tool
• Understanding unfamiliar codebases
• Mapping cross-file dependencies

4. **Parallel Processing**

• Offload tasks while continuing other work
• Run multiple code generations simultaneously
• Background documentation generation

5. **Specialized Generation**

• Test suite generation
• JSDoc/documentation generation
• Code translation between languages

When NOT to Use

• Simple, quick tasks (overhead not worth it)
• Tasks requiring immediate response (rate limits cause delays)
• When context is already loaded and understood
• Interactive refinement requiring conversation

Core Instructions

1. Verify Installation

command -v gemini || which gemini

2. Basic Command Pattern

gemini "[prompt]" --yolo -o text 2>&1

Key flags:

• `--yolo` or `-y`: Auto-approve all tool calls
• `-o text`: Human-readable output
• `-o json`: Structured output with stats
• `-m gemini-2.5-flash`: Use faster model for simple tasks

3. Critical Behavioral Notes

**YOLO Mode Behavior**: Auto-approves tool calls but does NOT prevent planning prompts. Gemini may still present plans and ask "Does this plan look good?" Use forceful language:

• "Apply now"
• "Start immediately"
• "Do this without asking for confirmation"

**Rate Limits**: Free tier has 60 requests/min, 1000/day. CLI auto-retries with backoff. Expect messages like "quota will reset after Xs".

4. Output Processing

For JSON output (`-o json`), parse:

{
  "response": "actual content",
  "stats": {
    "models": { "tokens": {...} },
    "tools": { "byName": {...} }
  }
}

Quick Reference Commands

Code Generation

gemini "Create [description] with [features]. Output complete file content." --yolo -o text

Code Review

gemini "Review [file] for: 1) features, 2) bugs/security issues, 3) improvements" -o text

Bug Fixing

gemini "Fix these bugs in [file]: [list]. Apply fixes now." --yolo -o text

Test Generation

gemini "Generate [Jest/pytest] tests for [file]. Focus on [areas]." --yolo -o text

Documentation

gemini "Generate JSDoc for all functions in [file]. Output as markdown." --yolo -o text

Architecture Analysis

gemini "Use codebase_investigator to analyze this project" -o text

Web Research

gemini "What are the latest [topic]? Use Google Search." -o text

Faster Model (Simple Tasks)

gemini "[prompt]" -m gemini-2.5-flash -o text

Error Handling

Rate Limit Exceeded

• CLI auto-retries with backoff
• Use `-m gemini-2.5-flash` for lower priority tasks
• Run in background for long operations

Command Failures

• Check JSON output for detailed error stats
• Verify Gemini is authenticated: `gemini --version`
• Check `~/.gemini/settings.json` for config issues

Validation After Generation

Always verify Gemini's output:

• Check for security vulnerabilities (XSS, injection)
• Test functionality matches requirements
• Review code style consistency
• Verify dependencies are appropriate

Integration Workflow

Standard Generate-Review-Fix Cycle

# 1. Generate
gemini "Create [code]" --yolo -o text

# 2. Review (Gemini reviews its own work)
gemini "Review [file] for bugs and security issues" -o text

# 3. Fix identified issues
gemini "Fix [issues] in [file]. Apply now." --yolo -o text

Background Execution

For long tasks, run in background and monitor:

gemini "[long task]" --yolo -o text 2>&1 &
# Monitor with BashOutput tool

Gemini's Unique Capabilities

These tools are available only through Gemini:

1. **google_web_search** - Real-time internet search via Google 2. **codebase_investigator** - Deep architectural analysis 3. **save_memory** - Cross-session persistent memory

Configuration

Project Context (Optional)

Create `.gemini/GEMINI.md` in project root for persistent context that Gemini will automatically read.

Session Management

List sessions: `gemini --list-sessions` Resume session: `echo "follow-up" | gemini -r [index] -o text`

See Also

• `reference.md` - Complete command and flag reference
• `templates.md` - Prompt templates for common operations
• `patterns.md` - Advanced integration patterns
• `tools.md` - Gemini's built-in tools documentation