Meta Muse connectors: what to build, how to submit

Meta opened Muse to outside connectors on 18 September 2026 and counted over 2,000 submissions within days. For a merchant the question is not whether to file but what a connector should carry that Shopify Catalog already does not. Here is what Meta has published, what is only reported, and where MCP stands.

Last updated: 26 September 2026.

Muse connectors are the apps and services Muse can act through. Meta runs two classes: directory connectors, which Meta reviews and lists, and custom connectors Muse writes itself from a service's API or CLI. Directory submissions are open at muse.ai/platform.

Two connector classes, in Meta's words

Muse is the agent Meta launched on 8 September 2026; Muse Spark is the model underneath it. Both connector classes belong to the agent.

Directory connectors. Meta's Help Center: "You can choose to connect Muse to apps and services provided by Meta or third parties. We call these Connectors." Muse is designed "to exchange with Connectors only the data that's needed for them to work for you" (Meta Help Center, read 26 September 2026).

Custom connectors. The same page: "you can ask Muse to create a Custom Connector", a process "which can involve retrieving API information from the service", with credentials in the "Secure Credentials Store". The caveat is Meta's: "Meta doesn't review custom connectors or how they use your information, so grant access with caution." Tarek Sheasha, VP at Meta Superintelligence Labs, gave the technical version on 8 September 2026: "Muse can also write its own custom connectors for other services you care about if they have their own APIs or CLIs."

Both run under one gate. Sentinel is "the sole permission authority" for connector actions and network egress, and purchases get "human in the loop approval with the exact details of the purchase every time" (Meta AI Research, 8 September 2026). How that approval meets the payment rail is in how AI agent payments work.

The submission page and its three steps

Submissions opened at muse.ai/platform on 18 September 2026 (Zuckerberg's post, 7:03 PM ET; CellCog, 19 September 2026). The page lists three steps:

Two more lines matter. "Editors will review connectors for featured placement", so listing and featuring are separate decisions. And the page carries no SDK, no fee, no timeline and no mention of MCP (Meta, read 26 September 2026). Meta's follow-up is reported, not published: a developer portal to "track status and manage your submission" is coming, and onboarding runs "in waves over the coming weeks" (Meta email, 24 September 2026, via Stacktree and PostFast).

What the form asks for is second-hand, from a company that filed on 19 September 2026 (Stacktree): name, company, website, example prompts, icon, whether the connector accepts payments, support contact, privacy and terms URLs. Connection type is "Existing MCP" (hosted endpoint plus docs) or "Raw API" (URL, optional OpenAPI spec). Auth is "API keys, OAuth with PKCE, or other." Have those ready before opening the form; the wider checklist is in Meta Muse for merchants.

How many have applied

Meta has given two figures and no live count. At Connect, Alexandr Wang, Meta's Chief AI Officer, cited "more than 1,500 applications in less than week" (TechCrunch, 23 September 2026). A day later Meta's email said "over 2,000 submissions in just the first few days" (Meta email, 24 September 2026, via Stacktree and PostFast). Trackers publish their own live-connector counts; they disagree and Meta has confirmed none, so we do not use them. Meta's Connect recap names ten retailers plus Shop Pay, PayPal, Expedia and Instacart (Meta, 23 September 2026); how each got there is in brands on Meta Muse.

Five doors into an agent, compared

A merchant now has five ways to be reachable by an agent. Only one is the Muse directory.

Sources: Meta, Shopify Help Center, OpenAI Developers, Google Merchant Center Help, all read 26 September 2026. The third column decides most merchant plans: an eligible Shopify store is in Muse without filing anything.

What a merchant connector should expose beyond Catalog

Shopify Catalog carries "title, description, options, images, price, availability, and other key attributes" (Shopify Help Center, read 26 September 2026). That is discovery data, which is why optimising the product catalog for AI comes before any connector work.

What Catalog does not carry is everything after the order. "You remain the merchant of record, and you continue to manage fulfillment, returns, and customer service." Direct checkout also excludes "Subscriptions, Product bundles, Customizable products, B2B-only products" and "Local delivery, pickup in store, and pickup points" (Shopify Help Center). Those are the gaps a directory connector can fill:

• Order status. The most common post-purchase question; Catalog has no answer to it.
• Returns and exchanges. They stay with the merchant; a connector lets the agent start one under the merchant's policy.
• Loyalty and account linking. OAuth with PKCE, per the Stacktree reading of the form, is what linking needs.
• Store-level inventory and pickup. The one published commerce example is Instacart's scope: cart building, real-time store inventory, checkout and account linking (Instacart, 22 September 2026).
• Subscriptions and bundles. Excluded from direct checkout, so a connector is the only route.

Meta has published nothing on what the ten retailers' connectors expose; any description of their returns or loyalty handling inside Muse is vendor inference.

A connector does not fix attribution. On Meta-surface direct checkouts "Google Analytics and custom pixels won't fire"; orders arrive in Shopify admin attributed to Meta (Shopify Help Center). That is dark agentic commerce traffic, and the MyMuse case study shows what the GA4 gap looks like in a real account.

The MCP question, stated exactly

The record, in publication order:

1. Muse Spark 1.1 "zero-shot generalizes to new native tools, MCP servers, and custom skills" (Meta AI Research, 9 July 2026). A model statement.
2. The agent's launch documentation says custom connectors come from services with "their own APIs or CLIs" (Meta AI Research, 8 September 2026). MCP is not named.
3. muse.ai/platform does not mention MCP (read 26 September 2026).
4. Muse Code, the developer product, documents an mcp_servers block; the consumer app documents no MCP setting (read 26 September 2026).
5. A submitter reports "Existing MCP" as a form option (Stacktree, 19 September 2026). Reported.
6. Parallel.ai, a vendor, reports Muse "wrote a client using the official MCP SDK, connected over streamable HTTP" when handed an MCP URL (Parallel.ai, undated). Vendor test.

Our result sits at the level of item 6. Muse has no settings screen for MCP servers; we asked it to create a custom connector for our remote MCP server over streamable HTTP, it opened our sign-in page in its own browser, and the tools worked. The prompt and the domain check are in connect Tru Commerce from Muse. We connected. Meta has not said it supports MCP, and we do not say it for them.

One more source of confusion: Meta AI Connectors, in developer preview at dev.meta.ai, offers "guided UI or MCP onboarding" (Meta, read 26 September 2026). That is Meta AI, the assistant inside WhatsApp, not Muse; its page lists "Build with Muse Connectors" as a separate offering.

India: nothing to file yet

Muse runs in the United States and Canada; Meta has named no India date (Medianama, 9 September 2026), and no Indian merchant or payment name appears in the Connect list. For an Indian developer the nearer surface is the Meta AI Connectors preview, since Meta AI already runs inside WhatsApp. The UPI question is in Meta Muse in India; the surface across both products is on Meta AI and Muse for brands.

Where Tru Commerce fits

We have run this on Gray Porter and a group of US DTC brands: we made the product pages and checkout readable and finishable by an agent, then placed a real Muse order on the store. Gray Porter was also submitted to Meta's Muse connector directory on 22 September 2026 and is awaiting Meta's review. We have also submitted a directory connector for a group of our US merchants through muse.ai/platform; Meta has published no approval data yet, and neither have we. To have your catalog, checkout and agentic checkout path checked the same way before you file a connector, book a demo.