hz-unity-meta-movement-sdk-retargeting

MSDK Retargeting Config

Workflow: always start with the headless API

Don't hand-craft the JSON from scratch — the native side computes initial alignment, mappings, and T-pose data that would be tedious to write by hand. The right flow is:

1. Generate the default config by calling Meta.XR.Movement.Editor.MSDKUtilityEditor.RunDefaultRetargetingSetup(GameObject asset, string customDataSourcePath = null) via Unity MCP. This is the headless equivalent of clicking through the Retargeting Configuration Editor UI with all defaults (Next×3 → Validate → Done) and produces both artifacts:
   • <asset>.json — the retargeting config (this skill targets this file)
   • <asset>-metadata.asset — a small ScriptableObject linking the model to the JSON (rarely needs editing)
2. Inspect the generated JSON to verify joint mappings look right.
3. Hand-edit only if needed — the rest of this skill describes the JSON structure and the common tweaks.

The same RunDefaultRetargetingSetup API also backs the Assets/Movement SDK/Body Tracking/Run Default Retargeting Setup editor menu item, so a user who sees a project asset selected can trigger it from the menu too.

Calling it via Unity MCP

The Unity MCP Unity_RunCommand script runner can't see the Meta.* namespace from the wrapped harness; use reflection to invoke the public static method:

using UnityEngine;
using UnityEditor;

internal class CommandScript : IRunCommand
{
    public void Execute(ExecutionResult result)
    {
        var asset = AssetDatabase.LoadAssetAtPath<GameObject>("Assets/MyChar/MyChar.fbx");
        if (asset == null) { result.LogError("asset not found"); return; }

        System.Type editorType = null;
        foreach (var asm in System.AppDomain.CurrentDomain.GetAssemblies())
        {
            var t = asm.GetType("Meta.XR.Movement.Editor.MSDKUtilityEditor");
            if (t != null) { editorType = t; break; }
        }
        var method = editorType.GetMethod("RunDefaultRetargetingSetup");
        try { method.Invoke(null, new object[] { asset, null }); }
        catch (System.Reflection.TargetInvocationException tie) {
            result.LogError("RunDefaultRetargetingSetup failed: " + tie.InnerException);
            return;
        }
        result.Log("done; config at " + AssetDatabase.GetAssetPath(asset).Replace(System.IO.Path.GetExtension(AssetDatabase.GetAssetPath(asset)), ".json"));
    }
}