You are helping me build the following AI agent workflow.

## Goal
Inventory Reorders: Monitors inventory levels on a schedule, calculates reorder quantities, posts pending requests to Slack for approval.

## Specification
- What it does: You get automated inventory reorders that calculate exact quantities based on your sales history and send approval requests directly to Slack. Once you approve a request with a reaction, the system automatically emails the vendor and updates your Google Sheets status without manual follow-up.
- Trigger: Triggered by an event (Scheduled · daily)
- Autonomy: You approve along the way
- Expected setup effort: about an afternoon
- Tools/services involved:
  - Google Sheets: Store inventory and vendor data
  - Slack: Notify team and approve reorders
  - Gmail: Send vendor reorder emails
  - Code: Calculate stock runway and quantities

## Known pitfalls, handle each one explicitly in your implementation
1. Google Sheets webhook payloads may include hidden rows if not filtered correctly, add a check to skip empty or archived products.
2. Email authentication failures can cause orders to bounce, verify SPF and DKIM records are set up for your sending domain before launch.

## Reference implementation
https://n8n.io/workflows/16473 (workflow template)
Fetch and inspect this before building. If it matches my stack, adapt it;
if not, rebuild the pattern with my tools.

## Process requirements
1. Before building: ask me which of the listed tools I actually use and
   what my platform is (n8n / Make / code / other). Do not assume.
2. Adapt the pattern to my answers; do not force the reference stack.
3. Address every pitfall above; tell me how you handled each.
4. Provide a test plan I can run before letting this touch real data.
5. Ask before any step that sends messages, modifies data, or spends money.

Source: https://usecasesforagents.com/use-case/automate-inventory-reorders/ via usecasesforagents.com