from pathlib import Path

def test_v15_runner_exists():
    p=Path('scripts/run_v15_external_diagnostics.py')
    assert p.exists() and 'def diag' in p.read_text()  # executable source present

def test_v15_doc_has_stop_rule():
    s=Path('V15_EXTERNAL_DYNAMICS_DIAGNOSTIC.md').read_text()
    assert 'final diagnostic' in s and 'stop iterating' in s