/**
 * Recursion guard shared by every hook script.
 *
 * A Claude Code session spawned via @anthropic-ai/claude-agent-sdk inherits
 * the same plugin hooks as the parent CC session. If any hook script in that
 * child session calls back into /agentmemory/* (e.g. Stop → /summarize →
 * provider.summarize() → another child session), we get unbounded recursion
 * that burns tokens and fills .claude/projects/ with ghost sessions
 * (#149 follow-up; see reported loop under v0.9.1).
 *
 * Two signals identify a SDK-child context:
 *   1. AGENTMEMORY_SDK_CHILD=1 env var — set by our agent-sdk provider
 *      before it spawns `query()`. Inherited by child processes.
 *   2. payload.entrypoint === "sdk-ts" — CC writes this into the hook
 *      stdin jsonl when the session was spawned by the Agent SDK.
 *
 * Hook scripts must call isSdkChildContext(payload) EARLY and return
 * silently when it is true.
 */
export function isSdkChildContext(payload: unknown): boolean {
  if (process.env.AGENTMEMORY_SDK_CHILD === "1") return true;
  if (!payload || typeof payload !== "object") return false;
  const p = payload as Record<string, unknown>;
  if (p["entrypoint"] === "sdk-ts") return true;
  return false;
}