Muse Code GA vs Claude Code vs Codex: Plans Compared
The Short Answer
Meta took Muse Code out of beta on September 1, 2026, adding three subscription tiers starting at $5/month, an SDK for building custom agents, multi-agent team workflows, and session rewinds.
The three terminal coding agents now sit at genuinely different points:
- Muse Code — cheapest, newest, with a data-for-discount tier attached.
- Claude Code — most mature agent behaviour, priciest subscription ladder.
- Codex — bundled into ChatGPT plans you may already be paying for.
Last verified: September 2, 2026.
Side by Side
| Muse Code | Claude Code | Codex | |
|---|---|---|---|
| Vendor | Meta | Anthropic | OpenAI |
| Status | GA Sep 1, 2026 | GA | GA |
| Entry plan | $5/mo | $20/mo (Pro) | $20/mo (Plus) |
| Underlying model | Muse Spark 1.2 | Claude Opus 5 / Sonnet 5 | GPT-5.6 Sol |
| API input / MTok | $1.25 | $5 (Opus 5) | $4 (Sol) |
| API output / MTok | $4.25 | $25 (Opus 5) | $20 (Sol) |
| Cached input | $0.15 | $0.50 | — |
| Discount tier | $0.10/$0.20 (data used for training) | None | None |
| Agent SDK | New at GA | Yes | Yes |
| Multi-agent | New at GA | Yes (subagents) | Yes |
| Context | 1M | 1M (Opus 5) | Large |
Subscription tiers for Claude and ChatGPT are the standard published plans as of September 2026; both vendors also sell higher Max/Pro tiers with larger usage allowances.
What Actually Changed at GA
The SDK is the significant release. Muse Code shipped as a terminal tool; it now ships as a programmable platform. You can build your own agents on top of its sessions, tools, permissions and persistent state, and coordinate multiple subagents in parallel within a workflow.
This is Meta closing the gap with the Claude Agent SDK rather than inventing something new. But the strategic read is worth noting: the value of a coding agent increasingly sits in the harness — session state, permission model, tool routing, parallelism — not in the model behind it. All three vendors now agree on that, which is why all three ship an SDK.
Session rewinds address the failure mode every terminal agent user knows: the agent goes down a wrong path for fifteen minutes and you want the state from before it started, without losing everything after. Claude Code and Codex both have their own approaches; Muse Code now has one.
The three-tier subscription structure from $5 is a deliberate price attack. Meta is not competing for the developer who has already standardised on Claude Code — it is competing for the one who has not paid for any agent yet.
The Contributor Tier Is the Real Decision
Everything else on this page is normal product comparison. This is the part that requires an actual judgement call.
Contributor pricing is $0.10 input / $0.20 output per MTok against standard $1.25/$4.25 — roughly 20x cheaper. The consideration is that your data is used for training. That arrangement survived the move out of beta unchanged, and it remains contentious.
Where it is defensible: open-source contributions, personal projects, throwaway prototypes, learning. Code that is already public or that you do not care about loses nothing.
Where it is not: client work, proprietary codebases, anything under NDA, regulated environments, and any repository containing credentials or customer data. The discount is irrelevant against the exposure, and there is no partial opt-in — you cannot take the price and withhold the data.
The mistake to avoid is enabling Contributor for a side project, forgetting, and later running it inside a work repository. Configure per-project, not globally.
How to Choose
Pick Muse Code if: you want the lowest possible cost, you work primarily on open-source or personal code, or you are building custom agents and want a cheap token floor under them. The $5 entry tier is the least painful way to test whether a terminal agent fits your workflow at all.
Pick Claude Code if: you are doing sustained work on a large proprietary codebase and want the most mature agent behaviour. On Anthropic’s own September 1 launch benchmarks Fable 5.1 leads Opus 5 on every reported evaluation, including 55.8% versus 52.3% on Terminal-Bench 4.0 — but Opus 5 at $5/$25 remains the sensible default engine for everyday work.
Pick Codex if: you already pay for ChatGPT. The marginal cost of trying it is zero, which beats every argument on this page for evaluation purposes.
The honest answer for most teams: the switching cost between these is now low enough that price should not decide it. Run the same real task — not a toy — through two of them on your own repository and compare completed work, not benchmarks. A 20x cheaper agent that fails twice as often is not cheaper.