> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.vapi.ai/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.vapi.ai/_mcp/server.

1. **Custom headers for custom LLM models**: You can now add custom `headers` to both [`Custom LLM Models`](https://api.vapi.ai/api#:~:text=CustomLLMModel) and [`Workflow Custom Models`](https://api.vapi.ai/api#:~:text=WorkflowCustomModel) (including in assistants, squads, and workflows). This lets you send custom HTTP headers—such as for authentication or extra metadata—when Vapi calls your custom LLM API. The `headers` property overrides default headers (except `Authorization`, which should be set via your custom-llm credential).