Muse Code vs. Codex: Meta’s and OpenAI’s coding agents compared
Muse Code edges OpenAI’s Codex on independent coding-agent benchmarks, but Codex comes bundled with ChatGPT and runs in far more places. Plans, prices, scores, speed, open-source status, and where Cursor fits in.
The short answer
On the same independent benchmark, Meta’s Muse Code with Muse Wonder Full scores a little higher than OpenAI’s Codex with its strongest model, and does particularly well at answering questions about a codebase. Codex has the reach: it comes with every ChatGPT plan, runs in a desktop app, an IDE extension, the web, and on your phone, and its CLI is open source. Muse Code is a terminal tool with plans of its own, starting at $5. If you already pay for ChatGPT, start with Codex; if you want the stronger agent for coding in the terminal at a low monthly price, Muse Code is worth the separate subscription.
Side by side
| Muse Code | Codex | |
|---|---|---|
| Maker | Meta | OpenAI |
| Models | Muse Spark 1.3, Muse Wonder, Muse Wonder Full | GPT-6 Astra, GPT-6.1 Sol, GPT-6 Luna |
| How you pay | Its own plans: $5, $15, $50, $200 a month, or per token | Included in ChatGPT: Free, Go, Plus ($20), Pro (from $100), Business |
| Free option | None | Light use on ChatGPT Free and Go |
| Where it runs | Terminal on macOS, Linux, Windows | CLI, IDE extension, desktop app (Mac and Windows), web, iOS |
| Cloud tasks | No — runs on your machine | Codex Cloud on Plus and higher |
| CLI source code | Closed; SDK is public | Open source |
| Training on your code | Plans start in Contributor mode (on) | Controlled by ChatGPT’s data settings; business plans aren’t used for training |
Codex plan details come from OpenAI’s help center and pricing pages as of October 2026; OpenAI has changed its Pro tiers more than once this year, so check the current lineup before you buy.
Benchmarks
Artificial Analysis evaluates both agents with the same tasks. Each row uses the strongest model the agent offers, at maximum reasoning:
| Muse Code + Muse Wonder Full | Codex + GPT-6 Astra | |
|---|---|---|
| Coding Agent Index | 59 | 55 |
| FrontierCode v1.1 | 49% | 49% |
| Terminal-Bench 4.0 | 59% | 56% |
| SWE-Atlas QnA | 69% | 59% |
| Time per task | 34.9 minutes | 24.8 minutes |
| Tokens per task | 14.5M | 3.2M |
Muse Code leads on the index and clearly on SWE-Atlas, which tests how well an agent understands a large codebase. Codex ties on FrontierCode, finishes tasks about ten minutes faster, and uses far fewer tokens and turns to get there: about 39 turns per task against Muse Code’s 195.
The cheaper models change the picture. Codex with GPT-6.1 Sol scores 54 — almost as high as with Astra — at about $1.50 per task. Muse Code with Muse Spark 1.3 scores 46 at about $3.91 per task, and with Muse Wonder 52 at about $8.05. So the top of Muse Code’s range beats Codex’s, but Codex’s mid-priced model is the better deal per point.
Price
The two are sold so differently that the right comparison depends on what you already pay for.
- If you have ChatGPT Plus ($20), Codex costs you nothing extra and includes the CLI, IDE extension, cloud tasks, and code review. Muse Code would be a second subscription, from $5.
- If you pay for neither, Muse Code’s $5 Everyday Usage plan is the cheapest paid way into a frontier-class terminal agent; Codex on ChatGPT Free or Go is limited to light tasks in the desktop app.
- For heavy use, Muse Code’s Power ($50) and Maximum ($200) plans include Muse Wonder Full; ChatGPT Pro starts at $100 and currently has no five-hour limit in Codex, though weekly limits may apply.
- Per token, Muse Spark 1.3 costs $1.25 / $4.25 per 1M input / output tokens, or $0.10 / $0.20 on the Contributor tier. Codex with an API key bills at OpenAI’s API prices and works in the CLI, SDK, and IDE extension, but not in Codex Cloud.
Where they differ in practice
Parallel work. Muse Code’s design centers on persistent background agents, each in its own git worktree, with a worker and a reviewer on every task. That’s why it spends more turns and tokens per task — more agents are checking each other. Codex Cloud takes a different route to parallelism: you hand tasks to cloud sandboxes and review the results as pull requests, without tying up your own machine.
Surfaces. Codex is everywhere: terminal, editor, desktop app on Mac and Windows, web, and iOS. Muse Code has no desktop app or official editor extension; you run it in a terminal, including VS Code’s.
Openness. You can read and fork the Codex CLI’s source. Muse Code’s CLI is closed, though its SDK and session protocol are public, and Meta’s Muse Spark Open model has downloadable weights.
Switching and mixing
You don’t have to choose at the level of the whole setup:
- Muse Code imports Codex skills and settings.
muse skills import --from codexcopies your Codex skills, Muse Code also reads~/.codex/skillsand.codex/skills, and/migratebrings over Codex’s memory and MCP configuration. - Codex can run on Muse models. Meta documents a
~/.codex/config.tomlprovider pointing athttps://api.meta.ai/v1withwire_api = "responses", so Codex can drivemuse-wonder-1.0ormuse-spark-1.3on your Model API key. The full config is in our docs.
What about Cursor?
Cursor is an AI code editor rather than a terminal agent, and it’s one of the places Meta ships Muse Spark 1.3 — you can pick the model inside Cursor and use it under your Cursor subscription. That gets you Meta’s model in an IDE, but not Muse Code’s harness: no persistent background agents, worktree fan-out, or event log. If you want Muse in your editor, Cursor is the official route; if you want Muse Code itself, run it in Cursor’s terminal.
Which should you pick?
- Pick Codex if you already pay for ChatGPT, want cloud tasks and an app on every device, value an open-source CLI, or want the best score per dollar from a mid-priced model.
- Pick Muse Code if you want the higher top-end score in the terminal, especially on large codebases, at a low monthly price, and you like worktree-isolated parallel agents.
- Compare with Claude Code too: see Muse Code vs. Claude Code, and our comparison table for more rivals.