feat: Add Google Gemini plugin for Flyte

[andreahlert]

Summary

This PR adds a new plugin for integrating Google's Gemini API with Flyte, following the same patterns as the existing OpenAI and Anthropic plugins.

Features

• function_tool decorator: Convert Flyte tasks to Gemini function declarations automatically
• Automatic type conversion: Python type hints to JSON schema for tool input validation
• Agent class: Configure Gemini agents with model, instructions, and tools
• run_agent function: Execute agent loops that handle function calling and responses
• Support for sync and async tasks
• Manual function calling control: Uses AFC (Automatic Function Calling) disabled mode for explicit tool execution management

Usage Example

import flyte
from flyteplugins.gemini import function_tool, run_agent

env = flyte.TaskEnvironment("gemini-agent")

@env.task
async def get_weather(city: str) -> str:
    """Get the current weather for a city."""
    return f"Weather in {city}: sunny, 72F"

@env.task
async def agent_task(prompt: str) -> str:
    tools = [function_tool(get_weather)]
    return await run_agent(
        prompt=prompt,
        tools=tools,
        model="gemini-2.5-flash",
    )

Files Added

• plugins/gemini/ - Plugin package
  • pyproject.toml - Package configuration
  • README.md - Documentation
  • src/flyteplugins/gemini/agents/_function_tools.py - Core implementation
  • tests/test_agents.py - Test suite (19 tests)
• examples/genai/gemini_agent.py - Example workflow

Test Plan

• All 19 unit tests pass
• Type conversion tests (string, int, float, bool, list, dict, Optional)
• Function schema extraction tests
• FunctionTool creation tests (regular functions, Flyte tasks, async)
• Agent configuration tests
• Tool execution tests (sync and async)
• run_agent tests (tool calls, errors, max iterations, finish reasons)

Why Gemini?

Google Gemini is one of the leading LLM providers alongside OpenAI and Anthropic. Having first-class support enables users to:

• Choose the best model for their use case
• Easily switch between providers
• Use Gemini's unique capabilities (multimodal, large context windows, cost efficiency)

This plugin mirrors the Anthropic plugin's API design, making it easy to switch between providers.

[kumare3]

I dont think this is right, i have not looked at the anthropic plugin, but this will result in bugs and instability

[kumare3]

@andreahlert here is the updated anthropic plugin - do you want to update your google gemini plugin using this model - https://github.com/flyteorg/flyte-sdk/tree/main/plugins/anthropic

[andreahlert]

Hi @kumare3! LGTM

I’ve aligned the Gemini plugin with the Anthropic one. Let me know if you’d like any other changes.

[kumare3]

Not async?

[kumare3]

.aio is available on non async tasks too

[kumare3]

We updated the anthropic plugin, sorry for the confusion, can you change like that and we can merge this