> ## Documentation Index
> Fetch the complete documentation index at: https://radiusbrowser.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Claude

> Choose CLI or API-key authentication for Claude in Radius.

| Method      | Use it for                                                | How it works                                                   |
| ----------- | --------------------------------------------------------- | -------------------------------------------------------------- |
| **CLI**     | Claude subscription login, Bedrock, Vertex AI, or Foundry | Claude uses your normal home, settings, and shell environment. |
| **API Key** | An Anthropic key managed by Radius                        | Radius supplies the key to an isolated Claude home.            |

## What belongs where

| Part                  | Behavior                                                                                             |
| --------------------- | ---------------------------------------------------------------------------------------------------- |
| Claude runtime        | Radius bundles and versions it. You don't need to install Claude.                                    |
| User configuration    | Claude reads your normal `CLAUDE_CONFIG_DIR`, usually `~/.claude`.                                   |
| Authentication        | **CLI** uses the native Claude account or cloud environment. **API Key** uses Radius's secure store. |
| Project configuration | Claude loads applicable project and local settings.                                                  |
| Model selection       | Claude reports availability; Radius applies the selection for the conversation.                      |

Both methods use Radius's bundled Claude runtime. Radius asks the Claude SDK
for available models and displays the returned names and capabilities.

Claude's native default supplies the initial model. A model that you select in
Radius overrides it for the conversation.