Meta’s first AI coding agent, in your terminal.
Muse Code is Meta’s AI terminal coding agent for your most complex coding workstreams. Build, debug, and ship: it plans the work, fans it out to persistent background agents in isolated git worktrees, and logs every decision.
Watch it work.
Six features. One session. Zero collisions.
Muse Code built six game features simultaneously — each agent in its own isolated worktree. Nothing stepped on anything else, and every branch merged clean.
A one-line idea, shipped as a working app.
Describe the product in a sentence. Muse Code plans the build, stands up the stack, wires the pages, and validates the result — end to end, in your terminal.
From a video file to working software.
Drop an mp4 straight into the terminal — a fly-through of a vacation home becomes a finished marketing and booking page. Muse Spark reads video, images, audio, and PDFs, not just code.
From prompt to pull request in three steps.
Install in seconds
One command, then sign in with your Meta Developer account. No IDE, no plugins — just your terminal.
Describe the work
State the outcome in plain language. Muse plans the tasks and hands them to its persistent background agents, working in parallel.
Review and ship
Audit the event log, replay any decision, then merge clean worktrees. You stay in control of every diff.
Accelerate your build.
Muse Code is a fast and accessible coding agent powered by Muse Spark.
Multi-agent by default
Multiple agents coordinate on every task — workers in parallel, reviewers in the background — so you ship faster without sacrificing quality.
Isolated git worktrees
Every agent works in its own worktree — your working copy is never touched. No collisions, no clobbered files; changes merge only after review.
Fully auditable
Every action is transparent and traceable. Review generated code, understand AI decisions, and keep confidence with built-in visibility across your workflows.
Built for Muse Spark
Co-trained for tight integration: better tool use, fewer retries, higher-quality output than a generic wrapper — with a 1M-token context that holds your whole repo.
The model and the harness, trained as one.
Muse Code runs on Meta’s Muse Spark 1.3, which replaced 1.2 as its model on September 2, 2026. The Spark models are co-trained with the Muse Code harness itself — rejection-sampled agent trajectories, goal conditioning, and context compaction — and trained extensively on long-horizon work. Version 1.3 finishes the same coding work with about 20% fewer tool calls and 25% fewer tokens than 1.2, and asks a clarifying question instead of guessing when it’s stuck. Since October 12, `/model` can also switch to Muse Wonder, Meta’s new frontier model, and Power and Maximum plans add Muse Wonder Full.
A monthly plan, or pay per token.
Meta sells it as a monthly plan from $5 or pay-as-you-go on its Model API. We just lay out the options.
Prefer a flat monthly fee?Everyday $5·High $15·Power $50·Maximum $200Compare plans →
Questions, answered.
What is Muse Code?+−
Muse Code is Meta’s AI coding agent for the terminal, built by Meta Superintelligence Labs. It launched in beta in August 2026, left beta on August 31, 2026, and runs on Muse Spark 1.3 by default, with Muse Wonder and Muse Wonder Full available since October 12. It takes on complete software engineering tasks across large repositories — planning changes, writing code, and validating the results with persistent background agents.
Is Muse Code free?+−
Installing it is free; using it is not. You pay with a monthly plan — Everyday Usage at $5, High Usage at $15, Power Usage at $50, or Maximum Usage at $200 — or per token through the Meta Model API. Meta hasn’t announced a free tier. The cheapest option is the Contributor tier at $0.10 per 1M input tokens, which lets Meta use your sessions to improve its products.
Is Muse Code out of beta?+−
Yes. Muse Code left beta on August 31, 2026, adding monthly plans, inter-session messaging, multi-agent Workflows, and an SDK in developer preview. Install it with the one-line command, sign in with your Meta developer account, then choose a plan or bind an API key.
Does Muse Code work on Windows?+−
Yes. Meta now ships a native Windows installer: run irm https://dev.meta.ai/install.ps1 | iex in PowerShell. On Windows the agent runs commands in PowerShell instead of Bash, and voice input and inter-session messaging aren’t available. WSL2 still works if you prefer a Linux shell.
Is there a Muse Code desktop app or VS Code extension?+−
No. Muse Code is a terminal program: Meta publishes no desktop app, IDE, or official VS Code extension. You can run it in VS Code’s integrated terminal. Downloads advertised as a “Muse Code desktop app” or “Muse Code for Windows” are not from Meta.
Is Muse Code the same as Meta Muse?+−
No. Meta Muse, launched on September 8, 2026, is a consumer personal agent that handles errands like email, bookings, and forms, with a free tier plus Power ($20) and Maximum ($100) plans. Muse Code is the developer agent that writes code in your terminal, with its own $5, $15, $50, and $200 plans. Both run on Meta’s Muse models.
How do parallel agents avoid stepping on each other?+−
Each background agent operates in its own isolated git worktree. Changes stay separate until the main agent reviews and merges them, so there are no file collisions or conflicting edits.
Is my code used to train models?+−
It depends on how you pay. Monthly plans start in Contributor mode, which trades your content for more usage; you can turn it off in /settings. On the API, the Contributor models are far cheaper because sessions may be used for training, while the Standard models are never used for training.
How large a codebase can it handle?+−
Muse Spark 1.3 supports a 1M-token context window — enough to plan, refactor, and verify across large monorepos end to end, not just single files.
What is Muse Wonder, and which plans include it?+−
Muse Wonder is Meta’s first frontier model, released October 12, 2026. It’s bigger and stronger than Muse Spark and costs $4 / $20 per 1M input / output tokens on the Model API. Every Muse Code plan includes Muse Wonder; Muse Wonder Full, the strongest version, comes only with Power ($50) and Maximum ($200) and isn’t sold through the API.
Why did my Muse Code usage drain so fast on October 12?+−
On launch day, Muse Wonder and Wonder Full counted against plan limits faster than they should have. Meta’s Chief AI Officer Alexandr Wang confirmed the bug, and Meta said it fixed the problem and reset usage the same day. If your numbers still look wrong, contact Meta support.
Can I run Muse Code locally or offline?+−
Not on a normal laptop. Muse Spark Open, released October 15, 2026, has open weights, and Meta has shown Muse Code running on it on Apple hardware. But the model has 816B parameters and needs about 700 GB of accelerator memory; Meta’s demo used two Mac Studios. Meta hasn’t published a step-by-step local setup.
What’s the difference between Muse Spark Open and Muse Glimmer?+−
Both have downloadable weights. Muse Glimmer (August 2026) is a 30B model under Apache 2.0 that fits a single consumer GPU. Muse Spark Open (October 2026) is an 816B model under Meta’s custom Muse Model License and needs workstation- or cluster-class hardware.
Is there a Muse Code plan above Power?+−
Yes. Maximum Usage, added on October 12, 2026, costs $200 a month and gives 80× the Everyday allowance, against 20× on Power. It includes everything in Power, including Muse Wonder Full. It isn’t the same as Meta Muse’s $100 Maximum plan, which belongs to the consumer agent.
Can I see what an agent did?+−
Yes. Every tool call and decision is written to a full event log. You can watch live, pause or redirect an agent mid-task, and replay any run step by step afterward.
Is Muse Code open source? Is it on GitHub?+−
The CLI isn’t: Meta ships it as a binary through its install scripts and hasn’t published the source. The Muse Code SDK is public at github.com/meta-models/muse-code-sdk (npm install @muse-code/sdk, or pip install muse-code-sdk for Python). For open models, Meta offers Muse Spark Open and Muse Glimmer with downloadable weights.
How do I update or uninstall Muse Code?+−
It updates itself, and rerunning the install command also fetches the latest build; muse --version shows what you have. Meta doesn’t document an uninstall command — on macOS and Linux, delete the muse launcher and its muse-bin-* files from ~/.local/bin, and settings from ~/.config/muse/. Cancel any plan separately in Accounts Center.
Is Muse Code down? Where can I check its status?+−
Meta has no public status page for Muse Code. The Model API does have a status endpoint, https://api.meta.ai/v1/status, that reports overall health and per-model availability without an API key. For account or billing problems, use the Help Center at dev.meta.ai/help.
Can Meta Muse write code?+−
Meta Muse, the consumer agent, is pitched for errands — email, bookings, forms, and shopping — not software projects. For code in your repositories, Meta’s product is Muse Code, a separate subscription from $5 a month. Both run on Meta’s Muse models, and a Muse subscription doesn’t include Muse Code.
Is there a Muse Spark 1.4?+−
Not as of late October 2026. Muse Spark 1.3, released September 2, is still the latest hosted Spark model; Muse Spark Open (October 15) is its open-weight sibling, and Muse Wonder (October 12) sits above both. The “1.4” you may have seen is the Muse Code CLI version (1.4.x), not the model.
Latest posts.
Muse Code API key: how to create one, use it in CI, and what it costs
Muse Code can sign in with a browser or an API key, and the key is also your way into Meta’s Model API. How to create a key, the environment variable each tool expects (META_API_KEY vs. MODEL_API_KEY), base URLs, per-token prices, rate limits, and the mistakes that cause surprise bills.
Read the post →Muse Code CLI cheat sheet: commands, flags, and shortcuts
Every Muse Code command worth knowing on one page: install and sign-in, slash commands, keyboard shortcuts, muse exec for CI, approval modes and --yolo, models and reasoning effort, skills, MCP, and where the config lives.
Read the post →Muse Code vs. Claude Code: price, benchmarks, and which one to use
Claude Code still edges Meta’s agent on most coding benchmarks, but Muse Code starts at $5 a month and its fastest runs finish in half the time. A side-by-side of plans, API prices, independent scores, privacy defaults, and how to switch between them.
Read the post →