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

# API Keys

> Connect your own AI provider API keys to use the writing assistant

LetterBucket's writing assistant can use your own AI provider API keys instead of the built-in AI. This gives you full control over which model you use and how costs are handled.

Go to **Settings → Profile → API Keys** to manage your keys.

## Supported providers

| Provider       | Key format                      |
| -------------- | ------------------------------- |
| **OpenAI**     | Starts with `sk-` or `sk-proj-` |
| **DeepSeek**   | Starts with `sk-`               |
| **OpenRouter** | Starts with `sk-or-v1-`         |

<Tip>
  OpenRouter is a good choice if you want access to many different models (including Claude, Gemini, Llama, and others) through a single API key.
</Tip>

## Adding an API key

1. Go to **Settings → Profile → API Keys**.
2. Select your provider.
3. Paste your API key. LetterBucket validates the key format before saving.
4. Save.

Once saved, the writing assistant in the editor will use your key for AI-powered features.

## Using the writing assistant

With a key connected, you can access AI assistance directly in the post editor:

* Select any text and use the AI actions in the formatting toolbar.
* Use the `/` insert menu to trigger AI-powered content generation.
* The assistant can help you rewrite, expand, summarize, or improve your writing.

## Removing a key

Click **Delete** next to any key to remove it. The writing assistant will fall back to LetterBucket's built-in AI if it's available on your plan.

<Warning>
  Your API keys are stored securely but treat them like passwords — don't share them. If a key is compromised, revoke it in your provider's dashboard and add a new one here.
</Warning>