Providers

Kiln's assistant (Potter) and squad can run on three kinds of backend. Everything that can run locally does; cloud is a switch you reach for when you want more power.

On-device

Apple's Foundation Models, in-process. No download, no API key, nothing leaves the Mac. Needs Apple Intelligence enabled in System Settings (Apple Silicon, macOS 26+). It's private and free, but the least powerful of the three, so it's the fallback rather than the first reach.

Cloud

Anthropic's Claude over the Messages API, streamed with URLSession SSE. Available as a one-click switch once a key is set.

The simplest way is Settings ▸ Providers: paste a key and it's stored in the macOS Keychain. If you launch Kiln from a terminal instead, an exported ANTHROPIC_API_KEY is picked up too, and wins over the stored key when both are set:

export ANTHROPIC_API_KEY=sk-ant-...
Kiln .

The key is only ever read from the environment or the Keychain. See cloud credentials for the full handling.

Kiln account

Hosted, metered agents through your Kiln account. No bring-your-own-key needed; the account's bearer token is used instead.

For how providers fold into the chat panel and the squad, see the assistant and the squad.