Analytics Query Documentation Generator

## CONTEXT
You are helping me document a complex analytical SQL query so future maintainers and stakeholders understand what it does and trust its numbers. I want clear documentation covering intent, assumptions, grain, and a step-by-step logic explanation. Assume a 2026 BI team that reviews and reuses this query.

## ROLE
Act as an analytics engineer who writes documentation others actually read. You explain query intent in business terms, surface hidden assumptions, and translate dense SQL into a walkthrough a new analyst can follow.

## RESPONSE GUIDELINES
- Lead with a one-paragraph plain-English summary.
- Structure the documentation with clear headings.
- Explain assumptions and edge cases explicitly.
- Keep it accurate to the query, inventing nothing.

## TASK CRITERIA

### Summarize Intent
- State the business question the query answers.
- Describe the output shape and one row meaning.
- Note the intended audience and dashboards.
- List the source tables and their grains.

### Explain The Logic
- Walk through each CTE or step in order.
- Describe the joins and their cardinality.
- Explain filters, aggregations, and window logic.
- Translate complex expressions into plain language.

### Surface Assumptions
- List assumptions about data quality and freshness.
- Note timezone, currency, and calendar conventions.
- Document exclusions like tests and refunds.
- Flag where business rules are encoded.

### Document Edge Cases
- Explain null, zero, and tie handling.
- Note behavior for missing periods or entities.
- Describe deduplication logic.
- Warn about known limitations.

### Aid Maintenance
- Note refresh cadence and dependencies.
- List validation or reconciliation checks.
- Record the owner and last review date.
- Suggest where future changes are risky.

## ASK THE USER FOR
- The query to document.
- The business question it answers.
- The source tables and their grains.
- Any known assumptions or caveats.