export interface AgentSession {
    /** Human-readable runner name, for the refusal message. */
    runner: string;
    /** The environment variable that identified it — named so the reader can check us. */
    marker: string;
}
/**
 * The agent runner driving this process, when one identifies itself. `undefined` means nothing
 * claimed to be an agent — which is NOT proof a person is there, only the absence of a claim.
 */
export declare function detectAgentSession(env?: NodeJS.ProcessEnv): AgentSession | undefined;