import type { RouterDecision } from "./types.js";
export interface RouterConfig {
    /** Master switch. When false, every call returns `{route: "ALL"}`. */
    enabled: boolean;
    /** Which engine fills the gap when heuristics are ambiguous. */
    mode: "heuristic" | "jina-classifier";
    /** Jina API key — required when mode === "jina-classifier". */
    jinaApiKey?: string;
    /**
     * Optional few-shot classifier ID. When provided, the router calls
     * `/v1/classify` with this ID instead of running zero-shot.
     */
    classifierId?: string;
    /**
     * Number of zero-shot classes to discriminate. Ignored when `labels`
     * or `classifierId` are provided. Default: 2 (NONE / ALL).
     */
    routes?: 2 | 4;
    /** Labels for zero-shot classification. Overrides `routes`. */
    labels?: readonly string[];
    /**
     * Minimum classifier confidence (cosine similarity in `[0, 1]`) required
     * to trust a classifier prediction. When `outcome.score` is below this
     * threshold, the router fails open to `ALL` with reason
     * `"classifier_low_confidence"` rather than acting on a noisy decision.
     *
     * Rationale: Jina v3 zero-shot scores cluster around 0.25 when none of
     * the labels actually match the query. Trusting only confident scores
     * keeps the gate fail-safe.
     */
    minConfidence?: number;
}
/**
 * Default applied by {@link decideRoute} when a caller omits
 * `minConfidence`. Matches the production default in the plugin schema.
 */
export declare const DEFAULT_MIN_CONFIDENCE = 0.35;
export interface RouterRuntimeContext {
    query: string;
    trigger?: string;
    /** Whether the messageProvider is the local CLI test harness. */
    isCli?: boolean;
    /** Optional AbortSignal propagated to the classifier HTTP call. */
    signal?: AbortSignal;
}
/**
 * Decide the route for one user turn.
 *
 * Returns a {@link RouterDecision}. The plugin caller logs `reason` and
 * uses `route` to gate the recall call.
 */
export declare function decideRoute(cfg: RouterConfig, ctx: RouterRuntimeContext): Promise<RouterDecision>;