Where can one find the AR Schema Developer Documentation?

I am manually using the USD sdk to create a .usdz file that displays a sequence of meshes, by using the timeSample attribute. I am able to view the .usdz file in usdview, and it shows the textured mesh sequence displayed correctly. However, when I attempt to open the same .usdz file on an iphone, it only displays the first mesh in the sequence (and the texture also doesn't appear). Does anyone know if Quick Look supports .usdz files with timeSamples, or what else may be causing this issue?Edit: to clarify, it is clear that the timeSample attribute is supported in some situations, as they are used in some of the Quick Look Gallery examples. I'm specifically trying to use timeSamples within a Mesh prim. Like in this example file: TimeSampleCratePyramid.usdzexample usda code:```#usda 1.0( endTimeCode = 48 startTimeCode = 0)def Mesh "MeshSequence" { float3[] extent.timeSamples = { 0: [(-50, 0, -50), (50, 100, 50)], 24: [(-50, 0, -50), (50, 100, 50)], } int[] faceVertexCounts.timeSamples = { 0: [4, 4, 4, 4, 4, 4], 24: [3, 3, 3, 3, 3, 3], } int[] faceVertexIndices.timeSamples = { 0: [0, 3, 2, 1, 0, 4, 7, 3, 3, 7, 6, 2, 2, 6, 5, 1, 1, 5, 4, 0, 4, 5, 6, 7], 24: [0, 2, 1, 0, 3, 2, 0, 4, 3, 0, 1, 4, 1, 3, 4, 1, 2, 3], } point3f[] points.timeSamples = { 0: [(-50, 100, -50), (50, 100, -50), (50, 100, 50), (-50, 100, 50), (-50, 0, -50), (50, 0, -50), (50, 0, 50), (-50, 0, 50)], 24: [(0, 100, 0), (-50, 0, -50), (50, 0, -50), (50, 0, 50), (-50, 0, 50)], } }```