Gemini Cli

gemini-cli

Status: ✅ Production-Ready | v2.0.0 | Last Updated: 2025-11-13

Use the official Google Gemini CLI directly from Claude Code for second opinions, architectural advice, debugging help, and comprehensive code reviews using Gemini's 1M+ context window.

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Auto-Trigger Keywords

This skill should activate when Claude Code encounters these scenarios:

Commands

• gemini (official CLI tool)
• gemini-cli (installation package)
• gemini-2.5-flash, gemini-2.5-pro (model names)

Use Cases

• "second opinion"
• "consult Gemini"
• "peer review"
• "architectural decision"
• "stuck debugging" (after 2+ attempts)
• "security audit"
• "compare implementations"
• "model comparison"
• "Flash vs Pro"
• "1M context window"
• "large codebase analysis"

Technologies

• Google Gemini
• Gemini CLI
• @google/gemini-cli
• AI pair programming
• AI-to-AI prompting

Scenarios (Proactive)

• Major architectural decisions (D1 vs KV, Durable Objects vs Workflows, etc.)
• Security-sensitive code (auth, payments, data handling)
• Large refactors (5+ files, core architecture changes)
• Context approaching 70%+ full
• Unfamiliar technology stack
• Debugging failures (2+ attempts on same bug)

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When to Use

✅ Use This Skill When:

• User asks major architectural question ("Should I use D1 or KV for sessions?")
• Writing security-sensitive code (auth, payments, PII)
• Planning large refactor (5+ files or core architecture)
• Stuck debugging after 2+ failed attempts
• Context approaching 70%+ capacity, need full codebase analysis
• Unfamiliar with technology stack or library
• Need to compare two implementations (old vs new, alternative approaches)
• User explicitly requests Gemini consultation
• Want complementary perspective on critical decision
• Need 1M+ context window for comprehensive analysis

❌ Don't Use This Skill When:

• Simple questions answerable with Claude's knowledge
• Trivial code reviews (small, non-critical changes)
• Every single decision (reserve for critical scenarios)
• API rate limits exceeded
• No internet connection available

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Quick Example

Scenario: User asks "Should I use D1 or KV for session storage?"

Claude's Workflow:

# 1. Detect architectural decision
# 2. Inform user: "Consulting Gemini for second opinion..."

# 3. Get Gemini's perspective (Pro model)
gemini -m gemini-2.5-pro -p "I'm building a Cloudflare Worker with 1000-5000 DAU. Should I use D1 or KV for session storage? Consider: 1) Session reads on every request, 2) TTL-based expiration after 30 days, 3) Remember me functionality, 4) Multi-device tracking, 5) Cost under $50/month."

# 4. Synthesize both perspectives
# 5. Present unified recommendation

User sees:

Based on consultation with Gemini:

**My Perspective**: Both viable, depends on priorities
- KV excels at read performance (sub-millisecond)
- D1 provides better querying for multi-device tracking

**Gemini's Perspective** (2.5-Pro): D1 recommended
- Strong consistency is critical for sessions
- Query flexibility for "remember me" across devices
- Cost effective at this scale

**Recommendation**: Start with D1

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Installation

Via Marketplace (Recommended)

# Add marketplace
/plugin marketplace add https://github.com/jezweb/claude-skills

# Install skill
/plugin install gemini-cli@claude-skills

Manual Installation

# Clone repository
git clone https://github.com/jezweb/claude-skills.git
cd claude-skills

# Symlink skill
ln -s $(pwd)/skills/gemini-cli ~/.claude/skills/gemini-cli

Install Gemini CLI

# Install official Gemini CLI
npm install -g @google/gemini-cli

# Authenticate
gemini

# Test
gemini --version
gemini -p "What is 2+2?"

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Features

Core Capabilities

• ✅ Direct CLI Integration: Use official gemini command (no wrapper needed)
• ✅ Model Selection: Flash (fast) vs Pro (thorough)
• ✅ 1M+ Context Window: Analyze large code files
• ✅ Non-Interactive Mode: Perfect for Claude Code automation (-p flag)
• ✅ File Context: Pipe files or use --all-files
• ✅ AI-to-AI Prompting: Optimized prompts for Gemini from Claude

Use Cases Covered

1. Architecture Decisions: Technology selection, pattern choices
2. Security Audits: Authentication, payments, sensitive data handling
3. Debugging Assistance: Root cause analysis after failed attempts
4. Code Reviews: Before commits, pull requests
5. Refactoring Plans: Large-scale changes (5+ files)
6. Performance Optimization: Bottleneck identification

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Usage Patterns

Pattern 1: Quick Consultation

gemini -p "Should I use Drizzle ORM or raw SQL for Cloudflare D1?"

Pattern 2: Security Review

cat src/auth/middleware.ts | gemini -m gemini-2.5-pro -p "Security audit this auth middleware"

Pattern 3: Code Review

git diff HEAD | gemini --all-files -p "Review these changes for edge cases and security"

Pattern 4: Architecture Advice

gemini -m gemini-2.5-pro -p "Best way to handle WebSocket state in Cloudflare Durable Objects? Consider: 1) 100+ concurrent connections, 2) Persistence requirements, 3) Failover"

Pattern 5: Debugging

echo "[error message]" | gemini -p "Help debug this error. What's the likely root cause?"

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Comparison: gemini-cli vs google-gemini-api

Feature	gemini-cli (this skill)	google-gemini-api
Purpose	Second opinions, peer review	Direct API integration
Context	Full codebase (1M+ tokens)	Request-specific
Integration	Command-line tool	SDK (@google/genai)
Use Case	AI-to-AI consultation	Building Gemini-powered apps
Best For	Architecture, security audits	Chat, embeddings, function calling

Use both: gemini-cli for consulting Gemini, google-gemini-api for building with Gemini.

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Related Skills

• google-gemini-api - Gemini API integration via SDK
• google-gemini-embeddings - Gemini embeddings for RAG
• google-gemini-file-search - Managed RAG with Gemini
• openai-api - Alternative for second opinions

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Known Issues

1. Model Deprecation: gemini-2.5-flash-lite removed (use flash or pro)
2. Rate Limits: Space out requests if hitting limits
3. Large Files: Use --all-files carefully (can exceed context)

See SKILL.md for complete troubleshooting guide.

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Version History

2.0.0 (2025-11-13):

• ✨ Complete rewrite for official Gemini CLI (removed gemini-coach wrapper)
• ✨ Direct CLI integration patterns
• ✨ Simplified to core use cases
• ✨ Updated for gemini CLI v0.13.0+

1.0.0 (2025-11-08):

• Initial release with gemini-coach wrapper
• Production testing and experimentation

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Contributing

Issues and improvements welcome:

• Issues: https://github.com/jezweb/claude-skills/issues
• Email: jeremy@jezweb.net

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License

MIT - See LICENSE

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Maintained by: Jeremy Dawes | Jezweb