Changelog / release
0.12.9 — Muse Glimmer, natively
Released 2026-08-10 · full changelog · GitHub releases
Meta released Muse Glimmer 30B and rapid-mlx serves it the same week — through its own vendored implementation of the architecture, with no external runtime dependency. The desktop app learns to hear and speak, and MCP tools arrive in desktop chat.
- Muse Glimmer 30B is served natively.
rapid-mlx serve muse-glimmer-30b-4bitruns Meta’s 29.6B dense reasoner on the standard text lane — sliding-window attention, 131K context — through a vendored backbone verified against the reference implementation to a 1.4e-5 max deviation on identical weights (#1802). The model thinks on a private channel and answers on another; rapid-mlx demultiplexes that wire intoreasoning_contentandcontent, and parses its ATEM tool-call envelope natively — streaming and non-streaming, including multi-turn tool results (#1791). Muse joins the release gate as the sixth agent-verified family (#1808), and the 4-bit weights (19.4 GB) are mirrored on the model CDN. The checkpoint’s vision tower ships in the weights but image input stays off until the multimodal path lands upstream. - The desktop app can hear and speak. A new Audio tab turns recordings into text and text into speech, in a voice you pick — all on your Mac (#1786).
- MCP tools reach desktop chat. The engine’s MCP support is wired through to the desktop app, so chat can call your configured MCP servers (#1787).
- Chat and Images keep more than one model warm. Budgeted multi-model residency lets the desktop hold a chat model and an image model at once instead of evicting on every tab switch (#1788).
- Models you already downloaded elsewhere are found. Weights another MLX runtime pulled are discovered and reused instead of downloaded again (#1785).
- Hybrid vision models stop crashing the batching engine. They are served through a serialized lane instead (#1798), and MLLM serves now expose their status metrics (#1781).
- Desktop paper cuts. An isolated first run uses cached models instead of re-downloading (#1801); overlapping memory confirmations no longer stack (#1800); math renders correctly in the shipped app (#1797); closing the main window behaves (#1795); the updater and image cache state were repaired (#1794); and a grounded answer that denies real-time access re-synthesizes once instead of shipping the refusal (#1784).