"""Prompt material for the model-facing Authoring CDSL contract."""
from __future__ import annotations

from functools import lru_cache
from pathlib import Path


_GUIDANCE = Path(__file__).resolve().parents[4] / "agent" / "skills" / "cad-authoring" / "SKILL.md"


@lru_cache(maxsize=1)
def load_authoring_guidance() -> str:
    try:
        return _GUIDANCE.read_text(encoding="utf-8")[:12_000]
    except OSError:
        return "Use cad.author.v1 only. Never create runtime IDs or selector tokens."