Plain-English summary
Xero is a desktop app. Your projects, sessions, and journals stay on your machine. The API keys you paste live in the operating system keychain. We never receive them, and they aren't written in plain text on disk.
When an agent calls a model, the request goes from your machine straight to the provider (Anthropic, OpenAI, Cursor, xAI, Google, OpenRouter, GitHub, Azure, Bedrock, Vertex, or local Ollama). We are not in the middle of those calls.