> ## Documentation Index > Fetch the complete documentation index at: https://aithing.dev/llms.txt > Use this file to discover all available pages before exploring further. # F*ck > FAQ *pronounced as* F*ck Frequently asked questions about [AI Thing](https://aithing.dev) AI Thing is now fully [open source](https://github.com/aithing-lab/aithing-mac) — give the project a star to support! ### 0. Why is this page named F\*ck? Because when you're looking for answers, you just want the **f\*cking answers** — fast, clear, no bullshit. So here they are. ### 1. Is this free? Yes — [AI Thing](https://aithing.dev) does **not** charge for usage. All features, including agents and automations, are completely free. We use BYOK — you buy credits from model providers for full control over costs. ### 2. Which models do you offer? We support all frontier models like **Anthropic Claude**, **OpenAI GPT-5**, and **Google Gemini 2.5 / 3**. You can **use multiple of them in the same conversation**. See the full list here: [BYOK Models](/features/byok-models) The open-source version lets you add your own models. ### 3. How do I get API keys? Each provider gives you an API key directly. Here are the links: * [**Anthropic Claude**](https://console.anthropic.com/settings/keys) * [**OpenAI GPT-5**](https://platform.openai.com/settings/organization/api-keys) * [**Google Gemini**](https://ai.google.dev/gemini-api/docs/api-key) Paste your key into **Settings → Models**, and you're ready to go. ### 4. Which agents do you have? Are they free? Yes — **all agents are free**. We offer many one-click [agents](/features/multiple-agents), including a complete Google Workspace agent *(Gmail, Docs, Sheets, Slides, Calendar, Drive, and more)*, GitHub, Notion, Asana, Linear, and many others. If you need an agent we don’t have yet, email us at **[help@aithing.dev](mailto:help@aithing.dev)**. ### 5. Can I add my own agent (MCP server)? Yes. You can add your own MCP server — remote (HTTP/SSE) or local (STDIO) — in seconds. Learn more: [Multiple Agents](/features/multiple-agents) ### 6. Do you sell data? Absolutely not. Read our [Privacy Policy](/privacy). We only collect minimal account information (name and email), and you can **avoid sharing** even that by using the open-source version. Nothing you send to the AI — conversations, files, context, or API keys — is ever stored on our servers. *** Have questions? Email us at **[help@aithing.dev](mailto:help@aithing.dev)**.