export declare function isImageMimeType(mimeType: string): boolean;
export declare function isVideoMimeType(mimeType: string): boolean;
export declare function isAudioMimeType(mimeType: string): boolean;
export declare function isPdfMimeType(mimeType: string): boolean;
export declare function isExcelMimeType(mimeType: string): boolean;
export declare function isCsvMimeType(mimeType: string): boolean;
export declare function isDocxMimeType(mimeType: string): boolean;
/** PDF, Excel (.xlsx + legacy .xls), Word (.docx), or CSV — types FilePreview renders inline. */
export declare function isPreviewableMimeType(mimeType: string): boolean;
/**
 * The type to TREAT content as, given what its sender declared and what it is
 * called. An honestly-declared type is never second-guessed — only an
 * uninformative one is resolved, and only from the filename, falling back to
 * the declaration when the extension is unrecognized too.
 *
 * Mirrors `resolveMimeType` in `@lotics/shared/file_type`, which is what the
 * server stores. The kit cannot import it (`primitives_purity.test.ts` keeps
 * `src/` free of `@lotics/shared`), so `mime_parity.test.ts` asserts the two
 * agree instead of trusting that they will.
 */
export declare function resolveMimeType(declaredMimeType: string, filename: string): string;