OS3 runs on an API key you bring from a supported model provider. You choose the provider and the model, and you pay that provider directly for what you use. This is what "BYOK" — bring your own key — means.
OS3 asks for a key during setup, in conversation. You can add more keys, or change which one OS3 uses, later in settings → api keys.
supported providers
| Provider | How models are chosen |
|---|---|
| Anthropic (Claude) | OS3 knows this provider's models and offers a list |
| OpenAI | OS3 knows this provider's models and offers a list |
| Google Gemini | Models are read from your account after the key is saved |
| OpenRouter | Models are read from your account after the key is saved |
| Vercel AI Gateway | Models are read from your account after the key is saved |
| Ollama Cloud | Models are read from your account after the key is saved |
| Z.ai, Z.ai Coding Plan | Models are read from your account after the key is saved |
| Moonshot (Kimi) | Models are read from your account after the key is saved |
| MiniMax | Models are read from your account after the key is saved |
| xAI (Grok) | Models are read from your account after the key is saved |
| OpenCode Go | Models are read from your subscription after the key is saved |
| Local model | A model served from one of your own connected computers |
| Custom provider | Any OpenAI-compatible endpoint you give OS3 the address of |
The list can change as models and providers change. What is in OS3 at the time is the list that counts.
how to add a key
- Create an API key with your chosen provider. If you create a restricted key, it needs to be able to list models and to call the models you intend to use.
- In OS3, open settings → api keys. If you already have a key saved, choose add provider.
- Pick your provider and paste the key. OS3 shows where to create a key for the provider you picked.
- Choose register key.
OS3 checks the key with the provider before saving it. A key the provider rejects — including one on an account with no credit left — is refused, with the reason.
Your key is write-only: after it is saved, OS3 only ever shows you a masked version of it.
choosing a model
OS3 sorts its work into two tiers, small and standard, so lighter work can run on a cheaper or faster model. Under models, each tier has three choices:
- key — which of your saved keys this tier uses,
- model — which of that provider's models it runs, and
- effort — how much reasoning the model does, for models that offer a choice. Leave it on default and OS3 picks one for the work.
Changes save as you make them.
For Anthropic and OpenAI, OS3 offers a list of models it already knows about. For every other provider, OS3 reads the list from your account after you save the key, and you have to choose a model before OS3 can run anything on it. Until you do, requests are refused with a message telling you to choose one.
using more than one provider
You can save keys from several providers at once. Each tier can use a different key, so you could run the standard tier on one provider and the small tier on another. A new key starts serving any tier that does not already have one; tiers that already have a key keep it until you change them.
using a local model
The Local model option runs a model on a computer you have already connected with rabbit agent, rather than on a provider's servers — for example with Ollama, LM Studio, vLLM or llama.cpp. It needs:
- a connected computer that is online,
- the local address the model is served at (OS3 offers the common ones), and
- the model's id.
An API key is only needed if your model server asks for one. You can also set a context window under advanced if the detected one is not right for your model. OS3 tests the connection before saving it.
images
OS3 can also use a model to understand, generate or edit images. Set one up under images on the api keys page:
- Choose add image model.
- Under type, pick what it is for: understand images, generate images or edit images.
- Under key, reuse one of your saved keys or choose new key, pick a provider and paste the key.
- Choose or type the model, then verify and save. OS3 checks it works before saving it.
Removing an image model also deletes the key saved for it.
changing or removing a key
A saved key cannot be edited: the provider and the key itself stay as they were registered. To rotate to a new key, add the new one, point your tiers at it, then delete the old one.
When you delete a key, any tier that used it moves to another saved key. If it was your only key, you need to add one before OS3 can run anything.
common questions
how much does OS3 cost?
OS3 is free. You pay your model provider according to its own pricing. See do I need to pay for an API key for free options.
can I use more than one provider at a time?
Yes. Save a key for each, then choose which key each tier uses.
what happened to dlam's own key screen?
Standalone DLAM is being retired. DLAM is now a capability inside OS3, and it uses the same keys you register here. See how to use DLAM in OS3.