> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cognite.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Contextualize CAD models in data modeling projects

> Use 3D nodes to review CAD node metadata and the CAD contextualization API to contextualize by linking CAD nodes to CogniteAsset instances.

## Contextualize

<Steps>
  <Step title="Review CAD node metadata">
    CAD node metadata is extracted during CAD model processing and stored in the 3D database. You can read this metadata through the 3D nodes endpoints and use it to build your own mapping pipeline.

    Use the 3D nodes endpoints to list and filter nodes for the CAD revision you want to contextualize:

    * [Filter 3D nodes](https://api-docs.cognite.com/20230101-beta/tag/3D-Model-Revisions/operation/filter3DNodes)
    * [List 3D nodes](https://api-docs.cognite.com/20230101-beta/tag/3D-Model-Revisions/operation/get3DNodes)

    <Note>
      Some integrations still need the internal numeric `cog_3d_model_<modelid>` and `cog_3d_revision_<revisionId>` to query nodes. If your workflow starts from a <span translate="no">CogniteCADRevision</span> instance, remap its external ID to the corresponding numeric revision ID before calling the nodes endpoints.
    </Note>
  </Step>

  <Step title="Create contextualization approvals">
    To create approvals that connect CAD nodes to <span translate="no">CogniteAsset</span> instances, use the [Create CAD contextualization](https://api-docs.cognite.com/20230101-beta/tag/3D-Contextualization/paths/~13d~1contextualization~1cad/post/) API endpoint ([*public preview*](/cdf/product_feature_status)).
  </Step>
</Steps>