Build a private AI agent
you ship as one file.
Write Python tools, test against a real open model running locally in your browser, and export the whole agent as a single standalone HTML file you can email, embed, or run offline. Your prompts never leave the tab.
A real LLM, running entirely in your browser — no install, no server.
From idea to a shippable agent in minutes.
No backend to deploy. No keys to wire up before you can test. Open a template, edit Python, run it right where you are.
Pick a template
Start from a curated agent — chat, data analysis, code review — with prompts and tools already wired.
Edit & run locally
Write Python that runs in-browser via Pyodide. Test against a local model instantly — no API key required.
Export one file
Download a standalone HTML bundle. It runs offline, embeds anywhere, or publishes to the marketplace.
Describe it. AI builds it for you.
Not sure where to start? Describe your agent in plain English. Your own API key goes straight from your browser to the LLM — AgentOp only sees the finished agent.
Describe your idea
"A research assistant that summarizes academic papers and extracts key findings" is enough to start.
AI writes the code
Bring your OpenAI or Anthropic key. The complete agent — HTML, Python tools, prompts and UI — is generated in seconds, entirely in your browser.
Run it immediately
You land on a working agent, ready to try. Customize, download, or publish it as a reusable template whenever you want.
Real Python tools, running in the tab.
Define tool schemas and handlers in Python and AgentOp executes them in-browser via Pyodide. Grammar-constrained (GBNF) function calling behaves identically whether you're on a local model or a cloud one.
- ✓Pyodide 0.29 runtimeThe full CPython scientific stack, no install
- ✓Unified tool callingSame schema works on every model family
- ✓Test as you typeRun against a local model with one click
Local by default. Frontier models on demand.
Need GPT-4-class output for a hard task? Flip a provider on and bring your own key. Keys are encrypted client-side with AES-256 and never touch our servers — so you stay in control of both your data and your bill.
- ✓OpenAI & Anthropic built inOr add a custom connector
- ✓Bring-your-own-keyEncrypted in your browser, never stored
- ✓Mix local & cloudCheap drafts locally, hard calls in the cloud
A browser tab vs. a hosted chatbot.
| AgentOp (local) | Hosted chatbot | |
|---|---|---|
| Where inference runs | ✓On your device | On someone's server |
| Install / account | ✓None — open a tab | App or sign-up |
| Works offline | ✓Yes, after first load | No |
| Your prompts & data | ✓Never leave the page | Sent to the cloud |
| Cost to run locally | ✓Free | Per-token billing |
| What you walk away with | ✓A file you own — no expiry | A subscription |
Built for people who don't want to hand their data to AI companies.
Developers
Prototype agents in Python without standing up any infra.
Privacy-first teams
Keep sensitive docs on-device — nothing is sent anywhere.
Educators
Hand out a single HTML file that just runs, offline.
Tinkerers
Fork, remix and break things with zero setup cost.
The questions everyone asks first.
Q.Is it really running locally?
Yes. The model downloads once, caches in your browser, and inference runs on your GPU. Open your network tab — it's empty during a chat.
Q.Do I need a GPU?
For local models, yes. They run on your GPU via WebGPU — Chrome or Edge on a machine with a graphics card, or an Apple Silicon Mac. Without a supported GPU, local inference is too slow to be practical, so bring your own OpenAI or Anthropic key instead — those work on any device.
Q.What about my data and prompts?
They never leave the page when you use a local model. There's no server to send them to.
Q.Can I still use GPT-4 or Claude?
Yes — bring your own key. It's encrypted client-side with AES-256 and never stored by us.
Q.What does sharing a file give the recipient?
The whole app. They open one HTML file and it runs on their machine, offline — no install, no account.
Q.How big are the downloads?
From ~0.5GB (Qwen 0.6B) to several GB for larger models. They cache, so it's a one-time cost per model.
Build a private AI agent today.
Free to start. No credit card. Test locally, then export a file you actually own.