Gemini 2.5 + LangGraph + Replit = AI Superpowers in Your Browser.

Thanks to Paul Couvert’s tutorial, you can now deploy a fullstack AI agent—powered by Google’s Gemini 2.5—without ever leaving your browser. Whether you’re a developer or an AI enthusiast, this is one of the easiest ways to get started with conversational agents using LangGraph on Replit.
Let’s walk through the process in just five simple steps.
Step 1: Import the Repo on Replit
- Go to Replit.com
- Click Create Repl → Import from GitHub
- Paste this GitHub repository link:
arduinoCopyEdithttps://github.com/google-gemini/gemini-fullstack-langgraph-quickstart
You’ve now cloned the full Gemini agent project into your own workspace.
Step 2: Install Dependencies and Configure the Backend
Once the import is complete:
Terminal Commands:
Run the following commands in the Replit shell:
bashCopyEditpip install -e ./backend && npm install --prefix frontend
make dev
API Configuration:
- In the
backend
folder, locate the.env.example
file - Rename it to
.env
- Open it, remove the comment symbol (
#
), and paste in your Google API key
Step 3: Update the Frontend Configuration
To ensure the frontend connects properly:
- Open the file:
arduinoCopyEditfrontend/vite.config.ts
- Replace the entire content of the file with the updated version found at this link:
Pastebin – Updated Vite Config
Step 4: Edit and Customize Your Agent
At this point, your agent is functional. To personalize it:
Use the Replit AI Assistant to make changes using plain English. For example:
- “Add a greeting message when the agent starts”
- “Enable the agent to summarize long articles”
- “Connect it to a weather API”
The assistant can automatically generate the necessary code updates.
Bonus: Skip Manual Setup
If you’d prefer to skip all manual steps, Paul Couvert has provided a pre-configured version:
- Visit: Gemini Fullstack Agent on Replit
- Click “Remix this app”
- Add your API key in the
backend/.env
file - Start the app
No command line or config edits needed.
What This Agent Can Do
This setup enables you to run a Gemini 2.5-powered agent that supports:
- Natural language conversations
- Multi-step reasoning
- API-based tool usage
- Custom instructions or task flows
With LangGraph as the underlying orchestration framework, the agent is modular, scalable, and easy to modify.
Final Thoughts
Building and deploying an AI agent used to be a complex process. Now, with the combination of Replit, LangGraph, and Gemini 2.5, you can get started in under 10 minutes. Whether you want to create a smart chatbot, a research assistant, or a task automation tool, this setup is an excellent starting point.
Follow us for more Updates