Work out why a meeting was missed and set up a tested email-to-calendar check with ChatGPT and Codex

Posted

Oct 15, 2026 by Dave W Plummer (@davepl1968)

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Last checked

Oct 19, 2026

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Method:

How we verify

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

Outcome

Dave W Plummer missed an important appearance and asked the ChatGPT desktop app, which has access to their Gmail, to work out how it happened. It found Plummer had noon in mind, the time of an earlier prep call, while the event started at 7:50 a.m. Pacific, with emails also mentioning 8:50 a.m. Mountain. When Codex then reconstructed the email trail, it found the organiser had cancelled the calendar invite sent to Plummer's regular address while sorting out a Teams login mismatch, and the later confirmation email had no new invite. With Codex, Plummer then set up a recurring agent that reads email threads, including changes and cancellations, adds missing calendar entries with the source email and link, and flags contradictions. Test alerts at first didn't notify on the iPhone; after checking alarms, sync and Focus settings, a test finally rang. It now checks every ten minutes while the Mac is awake; its first historical review was still running.

Agent

ChatGPT, Codex

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: Find out why an appointment never made it into my calendar, then help me set up a regular check that catches commitments in my email.

What I can give you (ask for whatever's missing):
- The event I missed and roughly when it was arranged: [DETAILS]
- Which email account and calendar I use: [DETAILS]
- My time zone and how I get reminders (phone, computer): [DETAILS]

Rules:
- Read the whole email thread, including later changes and cancellations, and give me a short timeline of what happened.
- Point out time-zone mix-ups and any invites that were cancelled or never sent.
- For the ongoing check, only add events I've actually confirmed, with the date, time zone, link and source email in the notes.
- Don't RSVP, invite anyone or send messages.
- Help me test that a reminder really notifies me on my phone before calling it done.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.

Output: A short explanation of what went wrong and a working, tested check with a note on how to pause or edit it.

You'll know it worked when: every confirmed commitment in my email shows up in my calendar with a reminder that actually goes off.

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: Find out why an appointment never made it into my calendar, then help me set up a regular check that catches commitments in my email.

What I can give you (ask for whatever's missing):
- The event I missed and roughly when it was arranged: [DETAILS]
- Which email account and calendar I use: [DETAILS]
- My time zone and how I get reminders (phone, computer): [DETAILS]

Rules:
- Read the whole email thread, including later changes and cancellations, and give me a short timeline of what happened.
- Point out time-zone mix-ups and any invites that were cancelled or never sent.
- For the ongoing check, only add events I've actually confirmed, with the date, time zone, link and source email in the notes.
- Don't RSVP, invite anyone or send messages.
- Help me test that a reminder really notifies me on my phone before calling it done.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.

Output: A short explanation of what went wrong and a working, tested check with a note on how to pause or edit it.

You'll know it worked when: every confirmed commitment in my email shows up in my calendar with a reminder that actually goes off.

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: Find out why an appointment never made it into my calendar, then help me set up a regular check that catches commitments in my email.

What I can give you (ask for whatever's missing):
- The event I missed and roughly when it was arranged: [DETAILS]
- Which email account and calendar I use: [DETAILS]
- My time zone and how I get reminders (phone, computer): [DETAILS]

Rules:
- Read the whole email thread, including later changes and cancellations, and give me a short timeline of what happened.
- Point out time-zone mix-ups and any invites that were cancelled or never sent.
- For the ongoing check, only add events I've actually confirmed, with the date, time zone, link and source email in the notes.
- Don't RSVP, invite anyone or send messages.
- Help me test that a reminder really notifies me on my phone before calling it done.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.
- Each morning, cross-check the next seven days of commitments against the calendar and tell me only if something's missing.

Output: A short explanation of what went wrong and a working, tested check with a note on how to pause or edit it.

You'll know it worked when: every confirmed commitment in my email shows up in my calendar with a reminder that actually goes off.

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://x.com/davepl1968/status/2110796715179876531