Muse Wonder

Runs MCP tools

Meta’s first frontier model, released 12 October 2026 by Meta Superintelligence Labs. It is larger than Muse Spark and built for long agent tasks, and it is the only Wonder model you can call through an API.

Vendor
Meta
Released
12 October 2026
Context
1.05M tokens
Input
Text, image, video, audio, PDF

Paste a server URL, pick a model, and watch it call your tools in a real conversation. No install.

No server of your own? Leave it blank and use one of the public mock servers.

MCP Evals

Can Muse Wonder actually complete tasks with your server?

One chat shows the tool calls work. An eval writes real tasks from your tool schemas, has Muse Wonder drive each one, and reports where it got the wrong answer even though every call succeeded. Pick Muse Wonder as the driver.

What Muse Wonder is

Muse Wonder sits above Muse Spark in Meta’s closed Muse line. It takes text, image, video, audio and PDF input, returns text, and has a 1M-token window. It launched alongside Muse Wonder Full, a stronger version that Meta keeps for Muse Code subscribers and does not serve through the API. Artificial Analysis scores Wonder 52 on its Intelligence Index, against 56 for Wonder Full and 58 for Claude Opus 5.5. Meta pitches two agent features: Active Memory, which carries context across conversations, and Active Focus, which keeps an agent working on its goal after it hits an obstacle.

What Meta says

  • DeepSWE 1.1: 78.8%, against 79.0% for Wonder Full and 74.2% for Claude Opus 5.5.
  • AutomationBench-AA (business workflows): 39.1, against 45.4 for Wonder Full.
  • Terminal-Bench 4.0-AA: 52.0, against 57.1 for Wonder Full.
  • JobBench (professional tasks): 70.5. SWE-Marathon (long-running coding): 53.1.

These are the vendor’s own claims, not measurements of ours. Run the model against your own server to find out whether they hold for your tools.

How it reaches MCP

  • MCP Playground’s Agent Studio: paste your server URL above and run Muse Wonder against it in the browser, with no Meta account
  • Meta’s Model API as muse-wonder-1.0, which is compatible with OpenAI and Anthropic tooling, behind any MCP client that accepts a custom endpoint

What to watch for

  • Most of the Wonder headlines are Wonder Full’s. The API model is the smaller one, and on Meta’s own table it is six points behind Full on AutomationBench and five on Terminal-Bench. Compare against the Wonder column, not the Full one.
  • Meta measured its scores at maximum reasoning effort. A run at the default effort is not the model on the benchmark table, so set reasoning_effort before you judge it.
  • OpenRouter lists tools, tool_choice and structured_outputs, but not seed, stop or parallel_tool_calls. You cannot pin a seed, so run a prompt more than once before you call a result a regression.

Run the same four-step task on Muse Wonder and Muse Spark 1.2 against the complex-schema mock: create_user_profile, process_order, analyze_data, then configure_workflow. Spark 1.1 led MCP-Atlas, and Wonder has no MCP-Atlas score yet, so this is how you find out whether the bigger model calls your tools any better. All the mock servers →

Available here

ModelModel ID
Muse Wondermeta/muse-wonder

Go deeper

Frequently asked questions

What is the difference between Muse Wonder and Muse Wonder Full?
Wonder Full is the stronger model, scoring 56 on Artificial Analysis’s index to Wonder’s 52. Meta keeps Full for Muse Code subscribers and serves only Wonder through its API and on OpenRouter.
Is Muse Wonder open source?
No. Both Wonder models are closed, with no downloadable weights. Meta’s open model in the Muse line is Muse Glimmer 30B.
Does Muse Wonder support tool calling?
Yes. OpenRouter lists tools, tool_choice and structured_outputs, and Meta’s API is compatible with OpenAI and Anthropic tooling. MCP servers work through any client that turns MCP tools into function calls.
Muse Wonder or Muse Spark 1.2 for MCP?
Wonder is the larger, newer model and scores higher on Meta’s coding and agent benchmarks. The Muse line’s MCP-Atlas lead belongs to Spark 1.1, and Wonder has no published MCP-Atlas score. Run both against your server here and compare.

Sources

Muse Wonder for MCP: Specs & Tool Calling — Test Free | MCP Playground