/** Injected stylesheet id. */
export declare const TOOLS_STYLE_ID = "dsh-ws-tools-merge-style";
/** Wiring for the tools placement. */
export interface SidebarToolsMergeOptions {
    /** Read the toggle (default on until resolved). */
    enabled: () => boolean;
}
/** The installed handle: re-evaluate the toggle, or tear the stylesheet down. */
export interface SidebarToolsMergeHandle {
    /**
     * Re-evaluate the toggle now.
     *
     * The production path re-syncs through the `enabled` callback plus the observer;
     * this method is the tests' explicit re-sync entry (see the handle.sync() calls
     * in test/sidebarToolsMerge.test.ts). The signature and behaviour are unchanged.
     */
    sync: () => void;
    /** Remove the stylesheet and stop observing. */
    dispose: () => void;
}
/**
 * Install the tools placement. One installation at a time: a second one takes the
 * stylesheet id over and the first one's writes go to a detached node.
 * @param options - the toggle access.
 * @returns the handle that re-syncs or removes the placement.
 */
export declare function installSidebarToolsMerge(options: SidebarToolsMergeOptions): SidebarToolsMergeHandle;