The 2026-04-30 staging incident traced back to workspaces booting with
ANTHROPIC_BASE_URL pointing at a non-Anthropic shim (MiniMax / OpenAI
gateway) but no explicit model configured. The adapter silently fell
back to "sonnet" — an Anthropic-native alias the upstream didn't
recognize — and the SDK --print probe hung 30s before timing out.
Platform's phantom-busy sweep then nuked the workspace at 10min,
producing "every workspace dead" with the root cause buried in a
30s subprocess hang.
Pre-validate the combo at adapter boot: when ANTHROPIC_BASE_URL host
is non-Anthropic AND no explicit model is set, raise ValueError with
an actionable message pointing to MODEL_PROVIDER / runtime_config.model.
Also log the resolved model + base_url_host every boot so future
failures explain themselves in the workspace logs without digging
into the SDK subprocess.
Tests live under tests/ with their own pytest.ini that anchors rootdir
there — keeps pytest from importing the package __init__.py (which
does the runtime-discovery relative import that requires
molecule_runtime installed). 7 tests cover: misconfig raises with the
right message, Anthropic-native passes, no-base-url passes, custom-url
+ explicit model passes, dataclass + dict shapes, unparseable URL
no-crash. CI runs them on every push/PR.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
