/**
 * The structural facts extracted from one throwable on a cause chain.
 * Rules match on these fields only — never on live objects — so the
 * same rule works for real Errors and for plain-object shapes that
 * crossed a workflow step boundary (structured clone strips prototypes
 * but keeps own fields).
 */
export interface ErrorLink {
    readonly name?: string;
    readonly message: string;
    /** Node/undici style error code (`ECONNREFUSED`, `EADDRINUSE`, …). */
    readonly code?: string;
    readonly statusCode?: number;
    /** Gateway error body discriminator (`rate_limit_exceeded`, …). */
    readonly type?: string;
    /**
     * Structured remediation authored at the throw site (eve's own error
     * classes carry it as an own property, so it survives structured
     * clone). Pass-through rules surface it as the summary hint.
     */
    readonly hint?: string;
}
/** The full cause chain of a throwable, outermost first. */
export interface ErrorSignals {
    readonly chain: readonly ErrorLink[];
}
/** Projects a throwable into the flat signals the rule engine matches on. */
export declare function extractErrorSignals(error: unknown): ErrorSignals;