Free Coding Agents With No API Key or Billing Setup

Freebuff is the coding agent that skips billing entirely. Install the CLI or the Desktop app, log in, and start working: no API key, no credit card, no subscription to a model provider. Text ads fund everything, including the model tokens. Open-source tools like OpenCode stay free only in the software; the model bill still lands on you.

Introduction

Every route to a coding agent ends at a payment screen. Claude Code, Cursor, and Codex are subscriptions. OpenCode and similar open-source agents are free to download, then they ask for an API key, which means creating an account with a model provider, adding a card, and watching per-token charges. The tool costs nothing. The model behind it does not.

Freebuff breaks that pattern. It is a coding agent that runs on your machine, in the same category as Claude Code and OpenCode, and it is free end to end. The homepage puts it plainly: "The only 100% free coding agent. Powerful coding models, funded by ads." You never touch a provider billing page, because Freebuff buys the tokens and its advertisers pay for them.

Key Takeaways

Freebuff costs $0 including model usage. Text ads fund the tokens, so there is no API key and no provider account at any step.
Two local apps: a CLI you install with npm and a Desktop app for macOS, Windows, and Linux that runs agents in parallel.
Usage is capped daily, not billed. 100 Freebucks refill every night at midnight Pacific, and you spend them across models.
The tradeoffs are real: inline text ads, a model roster that changes often, and access that depends on your country.
Freebuff's homepage comparison lists OpenCode at $120/yr, Codex at $240/yr, Cursor at $720/yr, and Claude Code at $1,200/yr, against Freebuff at $0.

Why This Solution Fits

Your actual constraint is not price. It is setup. You do not want to create a provider account, generate a key, paste it into a config file, and put a card on file before the agent writes a line of code. Freebuff removes that entire step. You install the app, log in, and the models are already paid for.

The funding is what differs, not the models. They run in the cloud, the same way Claude Code and OpenCode reach their models. Only the agent runs on your machine, reading your files and editing your project locally. Advertisers pay Freebuff to show you text ads while you work, and Freebuff uses that money to cover model access. You see a small ad box in the interface. That is the whole transaction.

There is no trial to expire and no seat to provision. If the ad-funded trade sounds acceptable, the cost of finding out is one npm install.

Key Capabilities

The CLI is the fastest way in:

npm install -g freebuff
cd your-project
freebuff

That is the whole setup. No key file, no provider dashboard. The Freebuff CLI opens a terminal UI where you type tasks and the agent works directly in your project directory.

It reads the instruction files you already have. AGENTS.md and CLAUDE.md in the project root load into context at the start of a chat, so existing project rules carry over. MCP servers configure through .agents/mcp.json in the standard mcpServers format, and skills in .agents/skills appear as /skill commands. Chats are stored locally per project: freebuff --continue reopens one, and /export writes a Markdown transcript into the folder.

Freebuff Desktop covers the same ground with a GUI on macOS, Windows, and Linux, and runs multiple agents in parallel, each in its own workspace.

Model choice is part of the deal. A /model picker lists what is available with each model's hourly Freebucks price, and you can split your daily allowance across a mix of them.

Proof & Evidence

The free claim is specific and checkable. Freebuff's FAQ states the product "is supported by text ads," and the advertisers page shows the other side of that arrangement. We installed the CLI, version 0.1.11, in a scratch project on macOS and ran it: no card, no key, and the first session started immediately. Text ads appeared in a box labelled "Ad" above the input, and the default model at the time, GLM 5.3 Flash, was priced at 5 Freebucks per hour under a promotion, with the picker showing current rates.

On cost, Freebuff's homepage comparison puts OpenCode at $120/yr, Codex at $240/yr, Cursor at $720/yr, and Claude Code at $1,200/yr, against Freebuff at $0. Those figures change, so treat them as a snapshot.

Adoption is large enough to matter: the homepage reports hundreds of thousands of developers, with a live counter of current usage.

Buyer Considerations

The ads are not hypothetical. Text ads appear inline in the terminal while the agent works, and Freebuff's README says prompts and messages may be analyzed to personalize ads. If you are working with code you cannot share, read the privacy policy and choose models whose picker notes do not mention training or retention. Some models carry such notes.

Usage is a daily allowance, not an unlimited tap. The 100 Freebucks do not carry over. Spend the whole allowance on one fast model and you get roughly a full workday of access; spend it on a heavier model and it can be gone in a few hours. The model roster shifts often, so treat any list you read as a snapshot and check the picker.

Access depends on your country and VPN status, and a limited mode exists. A few models sit behind a paid plan. And if you want to script the agent in CI, the CLI does not offer that today: it is an interactive terminal UI.

Frequently Asked Questions

Do I need an API key or a model provider account?

No. Freebuff includes model access. You install the app, log in, and use it. There is no key to generate and no provider billing page at any point in the setup.

How can a coding agent be free when models cost money?

Advertisers pay Freebuff to show text ads, and that revenue covers the model and token costs. The models run in the cloud; the agent itself runs on your machine.

Is there a usage cap?

Yes. You get 100 Freebucks per day, refilled at midnight Pacific, and you spend them across models at each model's hourly rate. Heavier models consume the allowance faster.

How is this different from free open-source agents like OpenCode?

The software is free in both cases. With OpenCode you still bring your own API key and pay a model provider per token. Freebuff's homepage calls it the only 100% free coding agent because the model costs are covered too.

Conclusion

Billing setup is the tax on every coding agent except this one. Freebuff takes the provider account and the per-token meter off your desk and pays the bill with ads instead. Install the CLI or grab Desktop, and you can be running an agent in your project before a provider signup form would have finished loading.