# APISchemaAdapter not loading in Houdini **URL:** \ **Category:** Hydra\ **Tags:** cpp\ **Created:** [December 3, 2023, 9:51pm UTC](https://forum.aousd.org/t/apischemaadapter-not-loading-in-houdini/1013 "2023-12-03T21:51:23Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![AbsolutViktor](https://avatars.discourse-cdn.com/v4/letter/a/e9bcb4/32.png) [@AbsolutViktor](https://forum.aousd.org/u/AbsolutViktor)\ **Post date:** [December 3, 2023, 9:51pm UTC](https://forum.aousd.org/t/apischemaadapter-not-loading-in-houdini/1013/1 "2023-12-03T21:51:23Z")
Hey everyone! I’ve built a SceneIndexPlugin with an APISchemaAdapter to a custom API Schema, which works fine in native USD 23.11, confirmed with usdview. However, I can’t get the adapter to work inside Houdini (tested with Karma and HoudiniGL for Houdini 20). Running with `TF_DEBUG=PLUG_*` show the plugin is loaded, and I’ve checked that my SceneIndex is in fact created. It’s just the adapter that doesn’t seem to get called. I’ve confirmed that the adapter is registered with `UsdImagingAdapterRegistry::GetInstance().GetAPISchemaAdapterKeys()`. Any ideas why this wouldn’t work? – I understand this might be Houdini specific, but perhaps someone here has done this successfully and can share some insight. Any input is much appreciated! 🙂 I’m running Houdini with both `USDIMAGINGGL_ENGINE_ENABLE_SCENE_INDEX` and `HD_ENABLE_SCENE_INDEX_EMULATION` using macOS Sonoma 14.1. All the best, Viktor ---
**Author:** ![robp\_sidefx](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.aousd.org/robp_sidefx/32/327_2.png) [@robp\_sidefx](https://forum.aousd.org/u/robp_sidefx)\ **Post date:** [December 5, 2023, 11:16am UTC](https://forum.aousd.org/t/apischemaadapter-not-loading-in-houdini/1013/2 "2023-12-05T11:16:18Z")
Hi Viktor, I saw you also created a post on the Houdini forum ([Usd APISchemaAdapter not loading | Forums | SideFX](https://www.sidefx.com/forum/topic/93379/)) which is where I’ll try to carry on the discussion.