/**
 * `weft tail <workflow-id>` — stream a workflow's token events as they replay
 * from the server's Server-Sent Events endpoint (`GET /v1/workflows/:id/sse`).
 *
 * Each SSE frame is parsed into a structured event and emitted as one line:
 * a compact JSON object under `--json` (valid NDJSON), or a TTY-formatted line
 * otherwise. The stream ends on the server's `done` event, when the connection
 * closes, or when the caller aborts (Ctrl-C) — all of which resolve cleanly
 * with exit code 0 rather than leaving the reader hanging.
 *
 * The consumer is factored as {@link streamWorkflowEvents} so tests drive it
 * with an injected `fetch` and `AbortSignal` instead of a real terminal.
 *
 * @module cli/tail
 */
import type { CommandOutput, TailCommand } from './types.ts';
/** A single parsed SSE frame surfaced to the tail sink. */
export type TailEvent = {
    readonly id?: string;
    readonly event: string;
    readonly data: string;
};
/** Minimal `fetch` shape the tail consumer needs; lets tests inject a stub. */
export type TailFetch = (url: URL, init: RequestInit) => Promise<Response>;
/** Dependencies injected into {@link streamWorkflowEvents} for testing. */
export type TailStreamOptions = {
    readonly url: URL;
    readonly token?: string;
    readonly signal: AbortSignal;
    /** Sink for streamed events (stdout, suppressed under `--quiet`). */
    readonly write: (line: string) => void;
    /** Sink for connection/status errors (stderr, never suppressed). Defaults to `write`. */
    readonly reportError?: (line: string) => void;
    readonly json: boolean;
    readonly fetchImpl?: TailFetch;
};
/**
 * Connect to the workflow SSE endpoint and emit each frame through `write`.
 * Resolves when the stream ends, the server emits `done`, or the signal aborts.
 * Returns the exit code (0 on a clean end/abort, non-zero on a failed connect).
 */
export declare function streamWorkflowEvents(options: TailStreamOptions): Promise<number>;
/**
 * Execute `weft tail`. Wires the process's SIGINT into an `AbortController` so
 * Ctrl-C ends the stream cleanly, and writes events to stdout. A bare
 * `weft tail` with no workflow id is not yet supported (system-wide tail needs
 * a server-side multiplexed SSE route); it returns a usage error pointing at
 * the per-workflow form.
 */
export declare function executeTail(command: TailCommand): Promise<CommandOutput>;