macOS 27.2 Ships Hidden fm CLI Connecting Apple and Third-Party Models

Apple quietly shipped a lightweight agent harness called 'fm' in macOS 27.2, letting developers call Apple's Foundation Models and third-party providers from the terminal. Tests reveal no default system prompt and a hardcoded /v1 endpoint; the author speculates Apple is paving the way for offering its own models as a service.

2026-09-20 ~ 2026-09-21 · 4 related posts

• Apple ships lightweight agent harness fm CLI in macOS 27.2, works with third-party models — gregbarbosa · 2026-09-20
• fm CLI details: no default system prompt, hardcoded /v1 endpoint blocks GLM testing — gregbarbosa · 2026-09-20
• Why third-party support in Apple's fm CLI? A bet Apple is teasing its own model service — gregbarbosa · 2026-09-20
• macOS 27 ships fm CLI to run Apple's on-device Foundation Models from terminal — rxwei · 2026-09-21