To add a custom file source, for example a database, pass a custom FileProvider.

return docs({
  // other options
  fileProvider: (/*options*/) => {
    // implementation
  },
});

export type SourceFileType =
  | { type: SOURCE_FILE_TYPE.LOCAL; name: string }
  | {
      type: SOURCE_FILE_TYPE.REMOTE;
      name: string;
      value: string;
    };

export type FileProvider<
  TFrontmatter extends Record<keyof TFields, string>,
  TOptions extends
    MDXBundlerServiceBaseOptions<TFrontmatter> = MDXBundlerServiceBaseOptions<TFrontmatter>,
  TFields extends FieldDefinitions<TFrontmatter, TOptions> = FieldDefinitions<
    TFrontmatter,
    TOptions
  >,
> = (
  options: MDXBundlerServiceOptions<TFrontmatter, TOptions, TFields>
) => Promise<SourceFileType[]>;