---
title: "Gemini 3.x, Google GenAI, multimodality, and grounding"
chapter: "06"
---

# Gemini 3.x, Google GenAI, multimodality, and grounding

The current stable Gemini family includes `gemini-3.6-flash` for balanced
agentic/multimodal work and `gemini-3.5-flash-lite` for low-cost high-volume
automation. Preview IDs are not stable production dependencies.

## Spring AI integration

Spring AI 2.0 uses the Google GenAI SDK integration:

```xml
<dependency>
  <groupId>org.springframework.ai</groupId>
  <artifactId>spring-ai-starter-model-google-genai</artifactId>
</dependency>
```

Use provider options for thinking, multimodal inputs, native tools, grounding,
and features not represented by common `ChatOptions`.

## Tools and structured output

Gemini can use managed Google Search, Maps, URL context, File Search, and code
execution, plus custom function calls. Function calling requests an
intermediate action; structured output constrains the final answer. Preserve
all required model response parts and tool IDs across a manual loop.

## Embedding 2

`gemini-embedding-2` is a GA multimodal embedding model for text, images,
video, audio, and PDF. It accepts up to 8,192 input tokens and produces 128–3072
dimensions; 768, 1536, and 3072 are recommended. Truncated vectors are
automatically normalized.

## Tuning reality

Gemini API model tuning is not currently supported: the last tuning model was
shut down in May 2025. Use prompts, RAG, tools, or another approved training
path; do not design around a dead endpoint.

## Lifecycle discipline

Read the Gemini changelog and deprecation page automatically in release
management. Model aliases, parameters, and preview capabilities can change.

## Feynman check

Gemini is a multimodal engine with Google tools. Explain why a stable model ID,
an embedding model, and a managed research agent are three different products.