#!/usr/bin/env python3
"""System prompt (text blocks + cache_control) with the Python SDK.

STATUS: LIVE_VERIFIED 2026-09-18 with anthropic 1.7.0 (.venv). Run: .venv/bin/python examples/anthropic/messages/system.py
Key comes from .env (loaded by scripts/live.py); never printed.
"""
import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parents[3]))
from scripts import live  # noqa: E402  (loads .env, gives log_request)
from anthropic import Anthropic  # noqa: E402

client = Anthropic()
MODEL = "claude-haiku-4-5-20251001"
msg = client.messages.create(
    model=MODEL, max_tokens=16,
    system=[{"type": "text", "text": "You are terse. Answer in one word.", "cache_control": {"type": "ephemeral"}}],
    messages=[{"role": "user", "content": "Reply with OK."}],
)
print(msg.content[0].text, "| cache_creation:", msg.usage.cache_creation)
live.log_request("anthropic", "POST", "/v1/messages", 200, 0.00004, "example system.py")