Question 1

Do I need an OpenAI API key?

Accepted Answer

No. Sign in with your existing ChatGPT account and Halv uses the plan you already pay for. If you'd rather use an API key, that works too.

Question 2

How can it use fewer tokens and still give the same answer?

Accepted Answer

Halv strips what the model was going to ignore — duplicated file context, stale history, boilerplate instructions — and keeps everything that changes the answer. When a request can't be compressed safely, it passes through untouched.

Question 3

Is my code safe?

Accepted Answer

Everything runs locally. Halv reads your repo on your machine, and nothing leaves except the model call itself — the same call your client already makes. Shell commands run in an OS sandbox behind approvals you control.

Question 4

Which platforms are supported?

Accepted Answer

macOS on Apple silicon today, free while in beta. Windows and Linux are next — leave your email and you'll hear the moment they're ready.

Question 5

How is this different from the ChatGPT app or Codex?

Accepted Answer

Same models underneath. Halv adds the compression layer, the project sandbox, and a live savings meter — you keep your workflow and your plan, and spend about half as much of it.

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