Set up a weekly Gmail clean-up script that protects receipts with Gemini

Posted

Mar 30, 2026 by Andrew Ledet (Ask Andrew, Substack)

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Last checked

Oct 18, 2026

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Method:

How we verify

Evidence: Described by posterThe person describes what happened in words, without screenshots or video.

Context: The prompt the writer shares is a version for readers; Gemini's exact replies aren't shown.

Outcome

Andrew Ledet was tired of repeating a two-hour manual inbox clean-up. Working with Gemini, they built a Google Apps Script 'Janitor' that audits top senders, does a dry run, then clears old promotions, social and update emails while skipping anything from themselves, starred, or that looks like a receipt or order. The first run deleted more than 5,000 emails in a few minutes, and it now runs automatically every Monday at 3 a.m.

Agent

Gemini

The source didn't share its exact prompt, so we wrote this from what it describes.

Before you start, ask me 1–3 short questions about anything important that's missing below. Keep them quick. Then do the task, checking in with me at the key points.

Goal: Help me build a weekly automatic Gmail clean-up that removes old clutter but never touches receipts, starred mail or things I sent.

What I can give you (ask for whatever's missing):
- Which Gmail categories I want cleaned (Promotions, Social, Updates)
- How old emails should be before they go
- Senders I always want cleared and anything I always want kept

Rules:
- Start with a script that only reports my top 20 senders by thread count.
- Then write a dry run that lists what would be deleted and the estimated space saved, and wait for my OK.
- Exclude anything from me, starred, marked important, or that looks like a receipt or order.
- Only then give me the final script and step-by-step instructions for a weekly time-based trigger.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.

Output: Three short scripts (audit, dry run, weekly clean-up) with plain-English setup steps.

You'll know it worked when: the clean-up runs on its own each week and nothing I need goes missing.

Before you start, ask me 1–3 short questions about anything important that's missing below. Keep them quick. Then do the task, checking in with me at the key points.

Goal: Help me build a weekly automatic Gmail clean-up that removes old clutter but never touches receipts, starred mail or things I sent.

What I can give you (ask for whatever's missing):
- Which Gmail categories I want cleaned (Promotions, Social, Updates)
- How old emails should be before they go
- Senders I always want cleared and anything I always want kept

Rules:
- Start with a script that only reports my top 20 senders by thread count.
- Then write a dry run that lists what would be deleted and the estimated space saved, and wait for my OK.
- Exclude anything from me, starred, marked important, or that looks like a receipt or order.
- Only then give me the final script and step-by-step instructions for a weekly time-based trigger.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.
- Explain how to switch the trigger off and where deleted emails go, in case I need to recover one.

Output: Three short scripts (audit, dry run, weekly clean-up) with plain-English setup steps.

You'll know it worked when: the clean-up runs on its own each week and nothing I need goes missing.

Before you finish: re-read my goal and constraints, check your answer against each one, and list anything you assumed or couldn't confirm.

Source

https://askandrew.substack.com/p/taming-the-unruly-inbox