You are helping me build the following AI agent workflow.

## Goal
Subscription Tracker & Reminders: Daily at 8 AM, it checks your Google Sheet for upcoming subscription renewals and sends timely reminders via Telegram.

## Specification
- What it does: Never miss a subscription renewal because this agent checks your Google Sheet daily at 8 AM and sends timely reminders directly to your Telegram. You can also chat with it in plain English to instantly add new subscriptions, update details, or look up billing dates without lifting a finger.
- Trigger: On a schedule (Scheduled · daily 8:00 AM)
- Autonomy: Fully hands-off
- Expected setup effort: about an afternoon
- Tools/services involved:
  - Google Sheets: Storing subscription data and billing info
  - Telegram: Sending reminders and receiving user commands
  - OpenAI Chat Model: Natural language understanding for subscription management

## Known pitfalls, handle each one explicitly in your implementation
1. Google Sheets API quotas may be exceeded during bulk updates so batch write operations instead of updating row by row.
2. Timezone mismatches can cause missed reminders so explicitly convert all dates to the user's local timezone before comparison.

## Reference implementation
https://n8n.io/workflows/7885 (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/subscription-tracker-reminders/ via usecasesforagents.com