You are helping me build the following AI agent workflow.

## Goal
Recruitment Rejection Email Sender: Every day at 18:00 IST, the agent sends personalized rejection emails to candidates marked as rejected in your Google Sheet.

## Specification
- What it does: You save time by automatically sending personalized rejection emails to candidates marked as rejected in your Google Sheet every day at 18:00 IST. This process uses Gmail templates while preventing duplicates through timestamp tracking and dry run modes for safe testing.
- Trigger: On a schedule (Scheduled · daily 18:00 IST)
- Autonomy: Fully hands-off
- Expected setup effort: about an afternoon
- Tools/services involved:
  - n8n: Workflow orchestration and automation logic
  - Google Sheets: Reading candidate status and details
  - Gmail: Sending personalized rejection emails via SMTP

## Known pitfalls, handle each one explicitly in your implementation
1. Gmail API quotas can be exceeded during bulk sends, so add a sleep node between batches to stay within daily limits.
2. Template variable mismatches will cause empty fields in emails, so validate all placeholder keys against the actual column headers in your source data.
3. Sensitive candidate data might leak if error logs are exposed, so configure n8n to mask personal information in any debug output or webhook responses.

## Reference implementation
https://n8n.io/workflows/7766 (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/automated-recruitment-rejection-email-sender/ via usecasesforagents.com