export declare const MAX_INLINE_FILE_BASE64_CHARS = 1000000;
export declare const MAX_INLINE_IMAGE_BASE64_CHARS = 5000000;
export declare function isInlineVisionMediaType(mediaType: string | undefined): boolean;
export declare function formatBase64CharBudget(maxChars: number): string;
export declare function isInlineReadableDocumentType(mediaType: string, fileName: string | undefined): boolean;
export type InlineAttachmentBlockReason = {
    kind: "no-data";
} | {
    kind: "unsupported-image-format";
    mediaType: string;
} | {
    kind: "unsupported-file-format";
    mediaType: string;
} | {
    kind: "undecodable-text";
    mediaType: string;
    reason: "invalid-base64" | "not-utf8" | "too-large";
} | {
    kind: "over-inline-limit";
    maxChars: number;
    actualChars: number;
};
export declare function describeInlineBlockReason(reason: InlineAttachmentBlockReason): string;
export declare function classifyInlineAttachment(att: {
    type?: string;
    name?: string;
    data?: string;
    text?: string;
    contentType?: string;
    referenceOnly?: boolean;
}): InlineAttachmentBlockReason | null;