On October 12, 2026, Meta launched two models that share a name and almost nothing else. Muse Wonder is a product you can call: it sits on the Meta Model API at $4.00 input, $0.20 cached input, and $20.00 output per million tokens, and inside Muse Code. Muse Wonder Full is a model you can only sit in front of: it exists exclusively inside a Muse Code subscription, on the Power Usage and Maximum Usage plans. The decision an operator makes before pointing either one at a real repository is not which model is smarter. It is which promise they are buying — and the seat’s default promise is not the one most buyers think they made.
The frontier model is a seat, not a SKU
Meta’s own availability table is the whole story in four cells. Muse Wonder (muse-wonder-1.0): available on the Model API, standard mode only, and in Muse Code on pay-as-you-go and every plan. Muse Wonder Full: not available on the API at all — Power Usage and Maximum Usage subscriptions only.
There is no back door. Setting reasoning effort to “max” on muse-wonder-1.0 does not select Wonder Full; Meta’s models page says so in plain words. Meta publishes no API model ID for Full. A team that wants Full behind its own product has, in the words of one launch-week review, no path at any price — businesses can test it inside Meta’s coding environment and cannot deploy it through the standard API.
The seat prices are printed on the Muse Code product page: Everyday Usage $5 a month, High Usage $15 at 5× the Everyday allowance, Power Usage $50 at 20×, Maximum Usage $200 at 80×. Power is the cheapest chair that includes Wonder Full. The allowances run on five-hour and weekly resets, and per the Terms, a subscription’s per-period allowance expires at the end of each period and does not roll over. On Maximum, when the allowance is gone, Meta’s documented way forward is to wait for the refresh.
The credential is a leash
The subscription applies to the API key Meta automatically connects during Muse Code CLI onboarding, and the subscriptions doc is explicit about the boundary: “This credential is for use with Muse Code only.” The Terms give the arrangement its legal name — a Coding Harness Subscription — and the same restriction: the connected key “may not be used to access the Services outside the coding harness or to circumvent your subscription’s usage limits or billing.”
Any additional API keys you create under the same account are billed pay-as-you-go, per token. So one Meta account holds two different commercial relationships at once: a flat seat that works only inside one CLI, and metered keys that work anywhere except that they can never call the frontier model. Budget them as two products, because Meta does.
The default is the decision
Here is the trap, and it is set by a default. “Muse Code subscriptions default to Contributor mode. In Contributor mode, you get more usage from your plan in exchange for letting Meta use your content — the prompts, code, files, and context you send, plus the model responses you get back — to train future Meta models.”
A careful buyer can still walk into it. Meta’s Model Designation Policy lists Muse Wonder and Muse Wonder Full as Standard Models — the tier whose use constitutes Standard Services, where content is not used for training. The same policy then overrides the list: “If you access the Services through a Coding Harness Subscription, you are considered to be using the Contributor Services by default regardless of which Meta Model you select.” Terms section 3.3 says the same. In Muse Code, Contributor mode is not a model name. It is a subscription setting, and it is on.
Turning it off is one toggle: open /settings in Muse Code. The help page states what the toggle does and does not do: “Turning Contributor mode off changes how much usage you get from your plan. It doesn’t change which plan you’re on.” How much usage changes, Meta does not publish — no ratio, no prompt count, no price difference appears in the documents. The honest line for a budget is that the size of the privacy discount is undocumented.
Meta’s own warning belongs in every seat-setup checklist, quoted exactly: “You must not submit sensitive, confidential, or personal information to the Discounted Services. If your use case involves processing personal information, please use Standard Services.” Accounts with Zero Data Retention cannot use Contributor mode at all — and ZDR itself is an organization-level enablement Meta’s sales team turns on for Model API accounts, not a toggle in the CLI, and it does not cover requests made with a personal account.
The switch does not reach backward
The off-switch is prospective. Terms section 3.3: a change to Standard applies “prospectively only; it would not apply to Content previously submitted to the Contributor Services, and Meta’s rights with respect to that Content under Section 6 will survive the change.” Everything a seat sent while the default was on stays under the training grant after you flip the setting.
Section 6.1 adds the subtler pull: “Content previously submitted to the Standard Services becomes Content submitted to the Contributor Services if it is included in any request to the Contributor Services, whether directly or as context or background for your prompts or instructions.” One later Contributor-mode session that pulls an earlier, clean conversation in as context reclassifies that content.
The commitments page softens the arrangement with a safeguard and then qualifies it: before using Discounted Services content to train models, Meta “takes steps designed to disassociate that Content from your Accounts” — but Meta may use the same content for “evaluation, safety, abuse, quality, and policy review” without first applying those steps. And section 6.1 acknowledges the output side: models trained on your content may produce outputs “similar or identical to your Content,” including for third parties.
The API shelf is labeled honestly
On the API, the same choice exists — as a separate model name, printed on the pricing page where a buyer can see it. Contributor mode “isn’t available for Muse Wonder on Model API.” For Spark it is a different SKU: muse-spark-1.3-contributor and muse-spark-1.2-contributor at $0.10 input, $0.002 cached, $0.20 output per million tokens, against standard Spark at $1.25 / $0.15 / $4.25 — capped at 150 requests per minute against 3,000 for the standard IDs. The Muse Code product page labels the two rows without euphemism: the Contributor row is “Used to improve our products”; the standard row is “Not used to improve our products.”
That is the contrast the seat hides. On the API, training is a priced, named, rate-limited variant a buyer selects on purpose. In the subscription, it is the factory setting of the harness — and the model table’s “Standard Model” label will tell a skimming buyer exactly the wrong story about which arrangement they are in.
The operator’s checklist
Decide the data arrangement before the repository, not after the first session. A public demo and a confidential codebase can run through the same agent on the same afternoon; they require different settings, and the setting is per-subscription, not per-conversation.
Turn Contributor mode off in /settings before any client code, customer data, or contract-confidential material enters the seat — remembering that the flip protects only what is sent afterward, and that earlier standard content follows it if it is ever pulled back in as context.
Buy the seat for the seat’s work. Wonder Full is a genuinely frontier tool for a person at a keyboard, and it is not a component. Anything your own product must call belongs on the API, in Standard mode, on keys you budget per token.
This desk tracks Meta’s platform as it changes; the full rate card and the contributor tier’s arithmetic are in Meta Model API Pricing & Limits, and every Meta piece hangs off the Meta AI desk hub. The short version to tape above the desk: the model in the seat is not the model on the shelf, and the seat’s most consequential setting is the one nobody remembers choosing.
