/**
 * codex-runner.ts — OpenAI Codex CLI process management
 *
 * Mirrors `claude-runner.ts`. Spawns the `codex` CLI binary with the user
 * prompt, streams output, captures token usage when reported by the CLI.
 *
 * Codex CLI: https://github.com/openai/codex
 * Default invocation pattern: `codex exec --json -m <model> -- <prompt>`
 *   - `exec`: run a one-shot prompt and exit (non-interactive)
 *   - `--json`: emit JSON-line events on stdout for streaming integrations
 *   - `-m, --model`: override the model
 *   - `--`: separator before raw prompt (when not using --stdin)
 *
 * Auth: Codex CLI handles its own authentication via `codex login` (OAuth
 * with ChatGPT account) or environment variables it reads itself. We don't
 * inject anything into the spawn env — we just inherit the parent process env
 * so the user's local Codex login is used as-is.
 */
import type { ChainStep } from "./types.js";
import type { ClaudeResult, ProcessTracker } from "./claude-runner.js";
export declare function validateCodexBinary(): void;
export declare function isCodexAvailable(): boolean;
/**
 * Spawns `codex exec` with the given prompt and step config. Streams output
 * via `onChunk` and resolves with the full result + token counts.
 *
 * Authentication is handled by the Codex CLI itself (codex login / OAuth /
 * env vars). The spawn inherits the parent process env so the user's local
 * Codex authentication is used as-is.
 */
export declare function runCodex(prompt: string, step: ChainStep, onChunk: (chunk: string) => void, executionId?: string, timeoutMs?: number, processTracker?: ProcessTracker): Promise<ClaudeResult>;