> For the complete documentation index, see [llms.txt](https://docs.flatredball.com/flatredball/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flatredball.com/flatredball/glue-reference/files/glue-reference-sourcefile.md). # SourceFile ### Introduction Files in FlatRedBall can support "external" or "source" files. A source file is a file which must be processed before it can be used by FlatRedBall. Source files enable using files created by 3rd-party applications to be used in FlatRedBall. For example, the source file functionality would allow you to use a .psd file (Photoshop file) as a texture file. However, for a source file to be usable, a specific program (which is often referred to as a "builder") must exist to convert the source file to a file format which is understood by FlatRedBall. For example if the source file were a .psd file, then the destination might be a .png, and a PSD to PNG builder would be needed. ### Source files require builders Glue must be told how to convert a source file to the file type that Glue understands. To do this builders must be set up. To set up a builder, see the [File Build Tool](/flatredball/glue-reference/files/file-build-tool.md) page.. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.flatredball.com/flatredball/glue-reference/files/glue-reference-sourcefile.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.