In short
- Meta launched Muse Code (beta), a terminal coding agent powered by Muse Spark 1.2, its up to date coding mannequin. It is out there now through the Meta Mannequin API and a curl set up script.
- The agent coordinates persistent background subagents and retains a replay-exact occasion log, so a crash resumes precisely the place it stopped.
- On Meta’s personal charts, Muse Spark 1.2 trails Anthropic’s Opus 5 on each coding benchmark proven, whereas beating OpenAI’s Codex and Google’s Antigravity on most.
Meta is the most recent tech big to ship a coding agent, racing to compete with main AI behemoths Anthropic and OpenAI.
“We’re excited to launch Muse Code (beta), a terminal coding agent powered by Muse Spark 1.2, our latest mannequin,” the corporate wrote in an official announcement. “This marks our subsequent step towards the frontier, with bigger and far more succesful fashions on the best way.”
As an agentic coding device, Muse Code is constructed for software program engineering throughout massive repositories. Per Meta, it “takes on complicated software program engineering duties throughout massive repositories: planning adjustments, writing code, and validating the outcomes. It will possibly coordinate a number of persistent subagents for every process, fixing tough issues sooner, extra precisely, and with much less intervention.”
The element that stands out is the runtime. Muse Code logs each mannequin name, device run, approval, and edit to an area occasion log that acts as a single supply of reality. “This single supply of reality makes the runtime replay-exact and restart-safe: after a crash, the agent can resume exactly the place it stopped,” Meta mentioned. For long-running jobs, that is the characteristic that issues greater than uncooked pace—and it is the half rivals have not made a promoting level.
It additionally ships with default abilities. The “/plan” command turns a process into an approval-gated plan, whereas “/grill” stress-tests that plan till it holds up and “/purpose” works towards profitable completion of the target much like what Hermes does. Meta mentioned it co-trained Muse Spark 1.2 with Muse Code so the core LLM and the agent work collectively in synergy.
The benchmarks, and the catch
Muse Spark 1.2 is a coding-focused replace to Muse Spark 1.1. Meta mentioned it “considerably scaled up coaching compute on coding duties whereas increasing coaching surroundings range, delivering enhancements in code era, complicated debugging, and end-to-end developer workflows.” The charts inform a transparent story.
On Terminal-Bench 2.1, Muse Spark 1.2 with Muse Code scored 82.9%, behind Claude Code on Opus 5 at 86.7% however forward of GPT-5.6 Terra on Codex (81.8%) and Grok Construct (81.6%).

DeepSWE 1.1, which measures agentic coding capabilities, was nearer: 59.3% for Muse versus 65.0% for Opus 5 and 64.8% for Codex. On Meta’s inside coding bench, Muse hit 70.6% to Opus 5’s 79.4%.
The speedup charts flip the order. Over 1,000-plus device calls, Opus 5 posted the largest acquire versus baseline (about 74–75%), with Muse Spark 1.2 mid-pack at roughly 61–69% relying on the run. Meta’s level is that the agent retains enhancing as device calls accumulate, the habits you need from a long-horizon coder.

Probably the most attention-grabbing demos are long-horizon and multimodal. In stress testing, Meta mentioned Muse Code “iteratively optimized GPU kernels over 1,000+ device calls (as much as 24 hours) on Nvidia Hopper GPUs.” Meaning it was capable of enhance over time.
There’s additionally a visual-coding angle. In a single demo, a person drops a fly-through video of a home into the terminal as an mp4, and Muse Code “interprets the video and produces a visually wealthy web site with reserving capabilities.” Studying uncooked video right into a working internet app is the multimodal pitch Meta has been making throughout the Muse line.
See the launch thread:
Right here’s an instance of Muse Code’s multimodal visible coding capabilities. On this demo, the person inputs a fly-through video of a house into the terminal as an mp4 file. Muse Code interprets the video and produces a visually wealthy web site with reserving capabilities. pic.twitter.com/3CAfIMYmAB
— AI at Meta (@AIatMeta) August 5, 2026
The sector is already crowded
That mentioned, Meta is late to the battle. OpenAI’s Codex already runs parallel cloud brokers; DeepSeek has constructed its personal rival to Claude Code and agentic instruments like Hermes or OpenClaw are already good substitutes with extra capabilities. Muse Code’s edge is the crash-safe runtime and the subagent design, not benchmark supremacy.
The danger is the standard one for agentic coding: an agent that resumes after a crash and retains calling instruments for twenty-four hours is highly effective and unpredictable. Meta is betting builders need that autonomy, and it is transport now.
Muse Code is out there for testing upon set up coming into this command:
curl -fsSL https://dev.meta.ai/set up.sh | bash
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