> ## 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.

> ## Agent Instructions
> Cognite Data Fusion (CDF) is an industrial DataOps platform. Prefer English docs unless the user asks for another locale.
> Follow /_llms/ index links recursively until you reach page URLs ending in .md. Fetch those Markdown twins instead of HTML.
> For REST APIs, default to calendar version 20230101 (stable). Use 20230101-beta or 20230101-alpha only if the user is on a preview API. Cite paths under /api-reference/concepts/<version>/ and the Cdf-Version header. Prefer the Python SDK (cognite-sdk) unless the user is in JavaScript/TypeScript.
> Start here by task: platform overview /cdf/index.md; data modeling /cdf/dm/index.md; data integration /cdf/integration/index.md; access /cdf/access/index.md; CDF Toolkit /cdf/deploy/cdf_toolkit/index.md; REST quickstart /dev/quickstart.md; Python SDK https://cognite-sdk-python.readthedocs-hosted.com/en/stable/; Atlas AI /cdf/atlas_ai/concepts/index.md; Flows apps /cdf/flows/index.md; MCP and IDE setup /dev/guides/ide_ai_integration.md.
> For implementation work, also load /skill.md.

# 3D Files

> Retrieve 3D files from Cognite Data Fusion (CDF).

The **3D files API** provides direct access to processed 3D file data stored in CDF. You can retrieve individual files or navigate directory structures for a given 3D file ID. These endpoints are typically used by 3D visualization tools to load model geometry, textures, and associated resources.

## Key concepts

When CDF processes a 3D model revision, it generates optimized output files (geometry, textures, metadata) that are stored as 3D files. Each file has a unique ID and may contain sub-paths for directory-like navigation. Visualization clients use these endpoints to stream 3D content efficiently.

## What you can do

* **Retrieve** a single 3D file by its ID.
* **Navigate** directory structures within a 3D file using sub-paths.

<Note>
  These endpoints return binary data and are primarily intended for use by 3D rendering applications, not for direct user interaction.
</Note>