/** Returns a trimmed URL safe for an `<img>`/`<video>` `src`, or `null`.
* Relative URLs and `http:`, `https:`, `blob:`, and `data:` are allowed. The
* platform parser performs the same control-character normalization as DOM
* URL sinks, preventing obfuscated schemes such as `java\tscript:`. */
export declare function safeMediaSrc(url:unknown,URLCtor?:typeof URL):string|null;
/** Returns a trimmed URL safe to pass to `fetch()`, or `null`. This shares the
* resource allowlist with media sources so text/image `data:` URLs remain
* usable, while navigation-only and executable schemes are rejected. */
export declare function safeFetchUrl(url:unknown,URLCtor?:typeof URL):string|null;
/** Returns a trimmed URL safe for a *navigation* `<a href>`, or `null`.
* `http:`, `https:`, `blob:`, `mailto:`, and relative URLs are allowed.
* `data:` is intentionally excluded because following it can open an active
* document; `mailto:` is allowed because it hands off to the mail client
* rather than navigating a document. Use `safeDownloadHref()` instead for an
* anchor that retrieves a resource (one carrying a `download` attribute). */
export declare function safeLinkHref(url:unknown,URLCtor?:typeof URL):string|null;
/** Returns a trimmed URL safe for a *download/open* `<a href>` pointing at a
* resource, or `null`. `http:`, `https:`, `blob:`, and relative URLs are
* allowed. This is `safeLinkHref()` minus `mailto:`: a mail handoff names no
* retrievable bytes, so pairing it with a `download` attribute is meaningless.
* The allowlist is a strict subset of `safeMediaSrc()`'s, so a URL that fails
* the media-src check necessarily fails this one too. */
export declare function safeDownloadHref(url:unknown,URLCtor?:typeof URL):string|null;
/** Returns a trimmed URL safe to navigate an active document to -- an `<iframe src>` or a full
* page navigation -- or `null`. Only `http:`, `https:`, and relative URLs are allowed; this is
* the narrowest allowlist in this module; see the scheme-set comment above for why `data:`,
* `blob:`, and `mailto:` are each excluded here even though one or more of the other sinks in
* this module allow them. */
export declare function safeDocumentNavigationUrl(url:unknown,URLCtor?:typeof URL):string|null;
/** Returns a trimmed URL safe for an `<iframe src>`, or `null`. An alias of
* `safeDocumentNavigationUrl()` named for its most common caller (`<lr-mcp-app>`'s sandboxed
* frame); the two names share one implementation because the underlying question -- "may this
* become an actively-navigated document?" -- is identical for both callers. */
export declare function safeFrameSrc(url:unknown,URLCtor?:typeof URL):string|null;