When all providers fail, raise RuntimeError.

Verify that analyze_batch preserves input order in results.

Verify that higher concurrency allows overlapping item processing.

_create_chained_client correctly parses provider chain string.

_create_chained_client rejects unknown providers in chain.

When webhook is disabled, notify() prints a yellow warning.

Env var exists but is empty string → ValueError.

When URL is empty (env var not set), notify() prints a yellow warning.

url_env configured but env var doesn't exist → url=None + console warning.

send_failure_notification sends notify with correct failure vars.

Failure notification timestamp reflects current UTC time.

When first provider returns empty/whitespace, fallback to second.

When first provider quota exhausted, fallback to second.

When first provider hits 429, fallback to second.

Feishu collapsible layout sends one card with collapsed item panels.

When fetch_reply_text=True, reply lines are appended under Top Comments.

fetch_reply_text defaults to False — verify config default.