/**
 * ACP-compatible front door for the unified runner.
 *
 * Implements the minimal Agent Client Protocol (ACP) local-agent lifecycle over
 * newline-delimited JSON-RPC on stdio: `initialize`, `authenticate`,
 * `session/new`, and `session/prompt`. A `session/prompt` runs the unified
 * injected runner and streams the final answer back as `session/update`
 * notifications before returning the prompt
 * turn's stop reason.
 *
 * The runner and input/output streams are injectable for deterministic
 * testing.
 */
import type { Readable, Writable } from "node:stream";
export declare const ACP_PROTOCOL_VERSION = 1;
export type AcpRunnerInput = {
    prompt: string;
    sessionId: string;
    requestId: string;
};
export type AcpRunnerResult = {
    finalOutput: string;
    runId: string;
    status: "succeeded" | "failed" | "skipped";
    evidence: string[];
};
export type AcpRunner = (input: AcpRunnerInput) => Promise<AcpRunnerResult>;
export type AcpAgentOptions = {
    runner: AcpRunner;
    input?: Readable;
    output?: Writable;
    protocolVersion?: number;
};
/**
 * Run the ACP agent loop until the input stream ends. Resolves when input
 * closes. Each line is one JSON-RPC message.
 */
export declare function runAcpAgent(options: AcpAgentOptions): Promise<void>;