You are helping me build the following AI agent workflow.

## Goal
Daily Product Newsletter Automation: Daily at 08:00, it pulls today's products from Google Sheets and sends a personalized HTML newsletter to each subscriber via Gmail.

## Specification
- What it does: Receive a personalized HTML newsletter every morning at 08:00 featuring today's products from your Google Sheets list. This automation filters the latest items, builds the email content, and delivers it directly to each subscriber via Gmail.
- Trigger: On a schedule (Scheduled · daily 08:00)
- Autonomy: Fully hands-off
- Expected setup effort: about an afternoon
- Tools/services involved:
  - Google Sheets: Store product data and subscriber lists
  - Gmail: Send individual newsletter emails to subscribers
  - Code: Filter products by date and generate HTML email content

## Known pitfalls, handle each one explicitly in your implementation
1. Gmail API has a daily sending limit of 100 emails for free accounts so you must chunk requests or upgrade if needed.
2. HTML email clients strip external stylesheets so you need to inline all CSS properties directly into the HTML tags.
3. Invalid email addresses will cause the script to throw an exception so validate the recipient column before calling sendEmail.

## Reference implementation
https://n8n.io/workflows/16364 (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/daily-product-newsletter-automation/ via usecasesforagents.com