Meta Ships Muse Spark 1.2 and Its First Coding Agent

Meta shipped Muse Spark 1.2 on August 5, 2026, alongside Muse Code, described as Meta's first terminal coding agent. It continues the closed, proprietary Muse line Meta started earlier this year as a break from the open-weight Llama models the company had previously built its reputation on - Llama 4 Scout remains the newest open-weight Llama, with no open Llama 5.

Muse Spark 1.2 is a reasoning model tuned for multi-agent workflows, with a 1M token context window and native text, image, video, audio, and PDF input. It priced at $1.25 input / $4.25 output per 1M tokens. On LMArena's text leaderboard it has 1492 Elo (rank 13, xhigh effort).

On the Artificial Analysis Intelligence Index v4.1.1, it scores 57 - close to GLM-5.3 and just behind Kimi K3.

Read Meta's announcement: research.meta.ai