Diagnosing failed data warehouse syncs

Work top-down when a data warehouse source or table is failing, stuck, or producing bad data: source → schema → recovery action. Do not jump straight to "resync from scratch" — that discards synced data and restarts from zero, which is rarely the right first step.

When to use this skill

• The user reports a specific sync is failing (e.g. "my Stripe source is red")
• A table has been in Running state far longer than expected
• Data in a warehouse table is stale, missing rows, or looks corrupt
• Latest rows aren't appearing despite the schema being marked Completed
• The user is choosing between cancel / reload / resync / delete-data and isn't sure which
• Another skill — typically auditing-warehouse-data-health — has surfaced a failing source or schema and the user wants to dig into it

Both entry points (user-reported and audit-handoff) use the same workflow; the audit just means you already know which item to diagnose and can skip Step 1's discovery search.