Meta launches Muse Code terminal coding agent powered by Muse Spark 1.2
On 2026-08-05 Meta Superintelligence Labs launched Muse Code (beta), a terminal coding agent for long-horizon software engineering, powered by a new code-focused model, Muse Spark 1.2 - Meta's answer to Claude Code, Codex CLI and Grok Build. Zuckerberg later said Muse Spark 1.2's weights would be open-sourced (no date given).
Key facts
- Muse Code (beta) and Muse Spark 1.2 announced 2026-08-05
- Plans, implements and validates multi-file changes across large repos using persistent async sub-agents
- Local append-only event log of every model call, tool run, approval and edit - replay-exact and restart-safe
- Muse Spark 1.2 also available in the Meta Model API with expanded global access
- Meta demo: Muse Spark 1.2 optimized KDA and MLA kernels for NVIDIA Hopper GPUs over 1,000+ tool calls
- Reported pricing: $1.25/$4.25 per 1M tokens, or $0.10/$0.20 if Meta may train on your code (MindStudio/secondary)
- Reported: on 2026-08-10 Zuckerberg said Muse Spark 1.2 weights will be open-sourced, date TBD
What happened
MSL released Muse Code, a CLI coding agent built around a simple agent loop plus asynchronous background agents, with crash recovery via a local event log. It runs on Muse Spark 1.2, a coding-specialized model evaluated on Terminal-Bench 2.1, DeepSWE 1.1 and an internal Meta coding bench (charts only, no numbers in the post).
Why it matters
Every frontier lab now ships its own terminal coding agent; Muse Code is Meta's entry into the most commercially valuable agent category of 2026.
Pricing and the open-sourcing pledge come from secondary sources and were not confirmed on the official post.
Changelog
- 2026-09-29: created
Related events
- Meta releases Muse Spark 1.1 and opens the Meta Model API public preview ★★★
- Meta returns to open weights with Muse Glimmer, a 30B Apache-2.0 agentic model ★★★★
Sources (4)
- officialMeta AI Research - Introducing Muse Code and Muse Spark 1.2
- officialMeta AI Developers - Meet Muse Spark 1.2 and Muse Code
- pressThe Register - Meta wants to get inside your terminal with its new coding agent
- pressMarkTechPost - Meta releases Muse Code (beta)
id: 2026-08-05-meta-muse-code-spark-1-2 · updated 2026-09-29 · open in the interactive timeline