Anthropic API
The Anthropic API provider connects Coeus directly to Claude using an API key. Good if you want to use Claude without installing the Claude Code CLI.
What you need
An API key from console.anthropic.com. You'll need to add a credit card and buy some credits (or sign up for a usage plan).
Setup
- Open Settings → AI Providers
- Find Anthropic API and click Configure
- Paste your API key
- Pick a model from the dropdown (Claude Sonnet is a good default)
- Click Save
That's it. Switch to the Anthropic API provider in the chat bar and start asking questions.
Choosing a model
| Model | Good for |
|---|---|
| Claude Opus 4 | Complex reasoning, long documents |
| Claude Sonnet 4 | Fast, handles most questions well |
| Claude Haiku | Fast, cheap, good for simple questions |
You can change the model at any time without losing your setup.
Cost
You pay per token (roughly per word). For reading and summarizing notes, the cost is low. Longer conversations and large documents cost more. Check anthropic.com/pricing for current rates.
Attachments and vision
The Anthropic API supports image attachments. Drop an image or PDF into your message and the model can read it.