Apfel

Apfel is a free, open source command line tool that unlocks the language model Apple ships with macOS. Recent versions of macOS include an on device model of roughly three billion parameters for Apple Intelligence, and Apfel exposes it through one Homebrew install, with no model downloads, API keys or configuration. Every token is generated locally, and no data leaves the Mac. It is aimed at developers and power users who want scriptable local AI at no token cost. One install provides three tools. The command line tool is pipe friendly and works with stdin, stdout, jq and shell scripts, with JSON output, output validated against a supplied JSON Schema, multi turn input from a messages file, file attachments and a code flag that returns only a shell command. A local server acts as a drop in OpenAI compatible endpoint, supporting the Chat Completions and Responses APIs, streaming, tool calling and structured output, so existing OpenAI SDK clients can point at it. An interactive chat mode manages context with five trimming strategies and supports system prompts. Apfel also speaks the Model Context Protocol, so MCP servers can give the on device model tools. The model has a 4,096 token context window and supports English, German, Spanish, French, Italian, Japanese, Korean, Portuguese and Chinese. Apfel is free and released under the MIT licence, and running it incurs no subscription or per token charges. It requires an Apple Silicon Mac running macOS Tahoe with Apple Intelligence enabled, and its capability is bounded by Apple's small on device model rather than a frontier cloud model.