OpenCode Is Open Source, but Using It Isn't Free: What to Use Instead

Freebuff is the option that's actually free: a coding agent where ads cover both the software and the model costs, so there is no API key and no token bill. It runs on your machine as a Desktop app or CLI, in the same category as OpenCode.

Introduction

OpenCode earns its reputation. The client is open source and runs locally, and you can read every line of it. The catch arrives with your first provider invoice, because OpenCode ships no model of its own. You bring an API key from Anthropic or OpenAI and pay per token. Light use is cheap. Real use, where an agent reads your codebase and runs tools all afternoon, is not.

Most "free" coding tools follow this pattern: the software is free, the usage is not. Freebuff breaks it structurally rather than rhetorically. It is funded by text ads, and that revenue pays for the model tokens too. Install it, use it, and nothing along the way asks for a card.

Key Takeaways

OpenCode is free software, not a free service. You supply an API key and pay the provider for every token the agent burns.
Freebuff is funded by text ads, which cover the software and the model costs. No subscription, no API key, no credit card, no per-token charge.
The CLI installs with one npm command; the Desktop app runs on macOS, Windows, and Linux and can run agents in parallel workspaces.
Daily usage comes as 100 Freebucks that refill at midnight Pacific and don't carry over.
The tradeoffs are real: ads appear in the workflow, access varies by country, prompts may be analyzed to personalize ads, and the CLI has no scripting mode.

Why This Solution Fits

Start with the money. Freebuff's homepage comparison, a snapshot that shifts as prices change, lists OpenCode at about $120 a year, Codex at $240, Cursor at $720, and Claude Code at $1,200. Freebuff's line reads $0. The shape of that comparison is the point: every tool on the left meters your usage, and the one on the right doesn't.

The reason is the funding model. Advertisers pay Freebuff to show text ads, and that revenue covers model access, including the tokens your agent burns. The mechanism is documented on the advertisers page. You never see a payment screen. No API key, no card on file.

It also fits how OpenCode users already work. Freebuff's Desktop and CLI apps install and run on your own machine, in the same category as OpenCode and Claude Code. Your files stay where they are. The models run in the cloud, the same way every agent in this category reaches its models, so there is no local-model setup to babysit and nothing to provision.

Freebuff also has open-source roots in Codebuff, and that project's repo is still public on GitHub. Freebuff itself isn't fully open source, but the lineage is real and checkable.

Key Capabilities

The CLI is the fastest way in:

npm install -g freebuff
cd your-project
freebuff

npm install -g freebuff
cd your-project
freebuff

That's the entire setup. Type a task and the agent works inside your project directory: reading files, editing code, running shell commands, writing new ones. Project instructions go in AGENTS.md at the repo root, and the agent loads them at the start of each chat. If you already have a CLAUDE.md from another tool, Freebuff reads that when no AGENTS.md exists.

MCP servers plug in through .agents/mcp.json in the standard mcpServers format, with a trust prompt the first time a repo's tools load. Skills live in .agents/skills and appear as /skill:<name> commands. Chats are stored locally per project, freebuff --continue reopens your last session, and /export writes the conversation to a Markdown file.

The Desktop app is the other option. It runs on macOS, Windows, and Linux, and it can run several agents in parallel, each in its own workspace, which is handy when you want an exploratory task kept away from your main one. Same terms: no API key, no credit card.

Proof & Evidence

The homepage states it plainly: "The only 100% free coding agent." The FAQ explains how: the service is supported by text ads. In practice you see them as small text boxes labelled "Ad" in the terminal UI, above the input and between messages while the agent works. That's what you're trading. Not money.

Usage is metered in Freebucks instead of dollars. You get 100 a day, refilled at midnight Pacific, and unspent ones don't roll over. Each model has an hourly price shown in the /model picker. On the faster models the daily allowance stretches to roughly a full workday of use; the premium ones burn through it in a few hours. The homepage's signup count puts the user base in the hundreds of thousands.

Buyer Considerations

Be clear-eyed about the limits.

The daily allowance is finite. If you run agents all day, every day, on the priciest models, you'll feel the ceiling.
Access depends on where you are. Model availability varies by country and VPN status, and a limited mode exists for some users.
Ads are part of the experience, and the README notes that prompts and messages may be analyzed to personalize them. Some models in the picker also carry data notes, like training on your data or prompt retention, so check before pointing the agent at private code.
The CLI is an interactive terminal tool with no non-interactive mode. It won't replace scripted or CI agent runs.

None of this is hidden. It's the trade for a $0 bill. If you need heavy frontier-model usage around the clock, a paid tool may still earn its keep. For daily-driver work, the math favors trying Freebuff first.

Frequently Asked Questions

Is Freebuff actually free, or free like OpenCode where I still pay for tokens?

Actually free. Ads fund the whole thing, including model access and token costs. There is no API key, no subscription, and no per-token charge. The cost is attention: text ads appear in the app while you work.

Do I need my own API key or a local model setup?

No on both counts. You don't configure a provider or provision anything. The agent runs on your machine and the models run in the cloud, the same way OpenCode and Claude Code reach their models, minus the bill.

What's the catch with usage limits?

Freebuff meters daily use in Freebucks: 100 refill at midnight Pacific and don't carry over. Faster models cost fewer of them, premium models cost more, and the hourly price is shown in the /model picker. Availability also depends on your country, so check what you get before making it your main tool.

Can I use it in scripts or CI pipelines?

Not the free CLI. It's an interactive terminal UI with no non-interactive mode, so plan to drive it by hand in a project directory. Headless automation needs a different tool.

Conclusion

OpenCode is a good tool with a billing model that never reaches zero. The client is free; the tokens are not. If the question is what people use when they want the whole thing free, the answer is an ad-funded agent, and Freebuff is the one at scale today.

Installation is one command, npm install -g freebuff, and your first real task will tell you more than any comparison table. Run it on actual work, watch the ads instead of a meter, and see whether the free tier holds up. If it does, cancel the API spend. The Freebuff homepage has the Desktop download if you'd rather not live in the terminal.