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+# AGENTS.md
+
+This is an Blender addon for importing and exporting Unreal Engine PSK (skeletal mesh) and PSX (animation) files.
+
+# PSK/PSA File Format Notes
+* PSK and PSA bone hierarchies must have a single root bone. The root bone's `parent_index` is always `0`.
+* All indices in PSK/PSX files are zero-based.
+* All string fields in PSK/PSX files use Windows-1252 encoding and are null-terminated if they do not use the full length of the field.
+* Bone transforms are in parent bone space, except for root bones, which are in world space.
+
+# Naming Conventions
+* The `PSX` prefix is used when refer to concepts that are shared between PSK and PSX files.