Gemini Guide

Look up Gemini API documentation and SDK patterns when building with Google Gemini. This skill brings Gemini docs TO Claude — it does not call Gemini.

Skill	Direction	Tool
gemini-guide (this)	Gemini docs -> Claude	WebFetch, local docs
gemini-peer-review	Code -> Gemini	Direct Gemini API

Documentation Sources

Check in this priority order:

Priority	Source	Best For
1	GitHub codegen_instructions	Always-current SDK patterns — fetch https://raw.githubusercontent.com/googleapis/js-genai/refs/heads/main/codegen_instructions.md
2	Google AI docs via WebFetch	Official docs — https://ai.google.dev/gemini-api/docs/{topic} (append .md.txt for markdown)
3	Local cached docs (if available at ~/Documents/google-gemini-context/)	Pre-fetched topics — 24 JS, 24 Python, 7 common

Lookup Workflow

When the user asks about a Gemini topic:

1. Check corrections first: Read references/deprecated-patterns.md — know what NOT to suggest before writing any code
2. Fetch latest SDK patterns: Get the GitHub codegen_instructions.md for always-current patterns
3. Map the query to a topic: Read references/topic-index.md — if local docs exist at ~/Documents/google-gemini-context/, read the matching file; otherwise use WebFetch on https://ai.google.dev/gemini-api/docs/{topic}.md.txt
4. Synthesise: Combine the documentation into a clear answer with working code examples. Always use the CORRECT patterns from step 1.

Quick Corrections

These are the most common mistakes. Apply these even without reading the full references:

Claude Might Suggest	Correct
@google/generative-ai	@google/genai
google-generativeai (Python)	google-genai
GoogleGenerativeAI	GoogleGenAI
genAI.getGenerativeModel()	ai.models.generateContent()
model.startChat() / chat.sendMessage()	ai.chats.create() / chat.send()
generationConfig	config
stream=True (method param)	config={"stream": True}
gemini-pro	gemini-2.5-flash
gemini-pro-vision	gemini-2.5-flash (unified multimodal)
4 safety categories	5 categories (include HARM_CATEGORY_CIVIC_INTEGRITY)
HARM_CATEGORY_DANGEROUS_CONTENT	HARM_CATEGORY_DANGEROUS (no _CONTENT)
X-Goog-Api-Key (capitalised)	x-goog-api-key (lowercase)
Daily rate limits	No daily limits — only per-minute (RPM, TPM)

Correct Initialisation (JS)

import { GoogleGenAI } from "@google/genai";
const ai = new GoogleGenAI({});  // auto-reads GEMINI_API_KEY env var
const response = await ai.models.generateContent({
  model: "gemini-2.5-flash",
  contents: "Your prompt"
});

Correct Initialisation (Python)

from google import genai
client = genai.Client()  # auto-reads GEMINI_API_KEY env var
response = client.models.generate_content(
    model="gemini-2.5-flash",
    contents="Your prompt"
)

Local Docs (Optional)

If you have a local cache at ~/Documents/google-gemini-context/, it contains:

Directory	Contents
javascript/	24 topic files — quickstart, function-calling, streaming, structured-output, etc.
python/	24 topic files — same topics as JavaScript
common/	7 cross-language files — safety, pricing, rate-limits, errors, auth, regions, openai-compat
rest-api/	REST endpoint docs
MODELS.md	Current model IDs, capabilities, token limits, rate limits
googlegenai-gemini-api.md	Comprehensive SDK guide (608 lines, JS + Python)

If not available, fall back to WebFetch on Google AI docs (append .md.txt for markdown format).

Current Models

Model	ID	Best For
Gemini 2.5 Pro	gemini-2.5-pro	Complex reasoning, advanced coding
Gemini 2.5 Flash	gemini-2.5-flash	Most tasks (recommended default)
Gemini 2.5 Flash-Lite	gemini-2.5-flash-lite-preview-06-17	Budget, low latency
Gemini 2.0 Flash	gemini-2.0-flash	Fast inference
Text Embedding	text-embedding-004	Semantic search, RAG (768 dims)

For full model details, check ~/Documents/google-gemini-context/MODELS.md (if available) or https://ai.google.dev/gemini-api/docs/models.

Maintenance

When information seems wrong or outdated:

1. Check the GitHub codegen_instructions.md (always current)
2. Verify model IDs against https://ai.google.dev/gemini-api/docs/models
3. Flag stale docs to the user

Reference Files

When	Read
Mapping a query to a documentation file	references/topic-index.md
Checking for deprecated patterns before writing code	references/deprecated-patterns.md