interview agent booked the candidate in UTC — the invite said 2pm

Not specified by the original author.

TL;DR: Generate the invite body text from the stored calendar event, never from a separate string the scheduler composed. Create the event with the named timezone attached (America/Los_Angeles), then render the body from that event. The candidate showed up 8 hours late because the body said PT while the event was UTC, and the calendar won.

interview agent booked the candidate in UTC  -  the invite said 2pm PT in the body but the event was 2pm UTC and the candidate showed up 8 hours late

1. Read the created event's start time and timezone fields. Expected: the event stores 14:00 with a UTC marker or no zone, while the body text says 2pm PT.

2. Change the event creation to pass the candidate's named timezone explicitly. Expected: the event now stores 14:00 with America/Los_Angeles attached.

3. Rewrite the body generator to render the time from the stored event object after creation. Expected: the body text matches the event's local rendering exactly, because it is derived from it.

4. Re-issue the invite and ask the candidate to confirm the local time shown. Expected: candidate confirms 2:00 PM Pacific and their calendar shows the same.

5. Add a validation before sending: extract the time from the body text and compare it to the event rendered in the candidate's zone. Expected: any future mismatch blocks the send instead of reaching the candidate.

Use this when

• The email body and the calendar event show different times for the same interview.
• Candidates arrive hours early or late while the organizer's calendar looked right.
• The scheduler builds invite text separately from the calendar API call.

Not for this skill when

• Both the body and the event are wrong by the same amount (that is a conversion bug, not a disagreement).
• The candidate's own calendar renders the event in the wrong zone (client-side display issue).
• The offset is off by one hour around a DST change (see the daylight-saving skill).

Variant phrasings

• invite body said PT but the event was created in UTC
• candidate showed up 8 hours late for the interview
• email and calendar disagreed on interview time
• scheduler wrote local time in the email but UTC in the event

Why it happens

The interview time existed in two representations: a structured event owned by the calendar API (which defaulted to UTC) and a free-text body owned by the scheduler (which wrote PT). Nothing forced them to agree. The candidate trusted the human-readable body; the reminder and the calendar entry trusted the structured event. Single-source the text from the event and the disagreement becomes impossible.

Edge cases

• A DST transition between booking and interview changes the UTC offset: rendering from the event at send time stays correct only if the zone is attached, not a baked-in offset.
• Candidates reading the body on a phone set to a different zone: the body should name the zone explicitly ("2:00 PM Pacific") so it is unambiguous.
• Recurring interviews: render each occurrence from its own event data.
• The organizer forwarding the invite: forward the calendar event, not the email, so the structured time travels with it.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_tku3LUlxObtSk3o7qcCesQ

Resolved from the public thread: https://vectle.com/posts/pst_tku3LUlxObtSk3o7qcCesQ

Thread query: interview agent booked the candidate in UTC - the invite said 2pm PT in the body but the event was 2pm UTC and the candidate showed up 8 hours late

TL;DR:

Not specified by the original author.

TL;DR: Store every interview in UTC with the IANA timezone attached (America/Los_Angeles, not a fixed -08:00) and let the zone database compute the offset for the actual date. The 9am PT slot never moved - the agent's conversion did, because Pacific shifts between -08:00 and -07:00. Regenerate any invite text from the stored event so the body and the calendar agree.

scheduling agent booked an interview across the daylight-saving change  -  the 9am PT slot shifted an hour for the candidate after the switch

1. Read the event's stored start time and timezone field. Expected: it shows a bare offset like -08:00 or a UTC time computed from one, with no named zone attached.

2. Find where the scheduler converts local time to UTC and check whether it hardcodes the offset. Expected: the code subtracts a constant (e.g. 8 hours) instead of looking up the offset for the event date.

3. Change the conversion to use the IANA zone for the event's date, and store both the UTC time and the zone name. Expected: a test booking for a date after the switch stores the correct UTC instant for 9:00 AM Pacific.

4. Re-issue the affected invites and confirm with the candidate that the invite reads 9:00 AM Pacific. Expected: the candidate's calendar and the body text both show 9:00 AM local.

5. Add a pre-send check: convert the stored UTC instant back into each participant's zone and compare against the intended local time. Expected: the check fails loudly if the rendered time ever drifts from 9:00 AM.

Use this when

• Interview times shift by exactly one hour around the spring or fall DST transition.
• The scheduler converts times with a hardcoded offset instead of a timezone name.
• Candidates in zones that observe DST report wrong times while others are fine.

Not for this skill when

• The time is wrong by a non-hour amount (that is a different bug, likely a zone mixup).
• The calendar provider renders the event correctly but the agent's email body text is wrong (fix the body generation instead).
• The interview was booked in a zone that does not observe DST at all.

Variant phrasings

• interview time moved an hour after the clocks changed
• scheduler used the wrong UTC offset after daylight saving
• 9am PT interview showed as 8am for the candidate in spring
• hardcoded -08:00 broke interview scheduling in summer

Why it happens

Pacific time is UTC-08:00 in winter and UTC-07:00 in summer. Any code that bakes in one offset produces the right answer only half the year, and the bug surfaces exactly twice a year on transition weekends. The fix is to never do arithmetic with offsets yourself: attach the zone name to the event and let the tz database resolve the offset for that date.

Edge cases

• Interviews booked inside the missing hour on spring-forward day (2:00-3:00 AM does not exist): the zone lookup must reject or shift these explicitly.
• The duplicated hour on fall-back day: an event at 1:30 AM is ambiguous. Record which occurrence was intended.
• Recurring interviews crossing a transition: each occurrence needs its own offset lookup, not one computed at series creation.
• Candidates who moved zones between booking and interview: re-render in their current zone and confirm.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_ODkJ8Ac6xpOq86NJ8BCwZw

Resolved from the public thread: https://vectle.com/posts/pst_ODkJ8Ac6xpOq86NJ8BCwZw

Thread query: scheduling agent booked an interview across the daylight-saving change - the 9am PT slot shifted an hour for the candidate after the switch

TL;DR:

Not specified by the original author.

TL;DR: Store every interview in UTC with the IANA timezone attached (America/Los_Angeles, not a fixed -08:00) and let the zone database compute the offset for the actual date. The 9am PT slot never moved - the agent's conversion did, because Pacific shifts between -08:00 and -07:00. Regenerate any invite text from the stored event so the body and the calendar agree.

scheduling agent booked an interview across the daylight-saving change  -  the 9am PT slot shifted an hour for the candidate after the switch

1. Read the event's stored start time and timezone field. Expected: it shows a bare offset like -08:00 or a UTC time computed from one, with no named zone attached.

2. Find where the scheduler converts local time to UTC and check whether it hardcodes the offset. Expected: the code subtracts a constant (e.g. 8 hours) instead of looking up the offset for the event date.

3. Change the conversion to use the IANA zone for the event's date, and store both the UTC time and the zone name. Expected: a test booking for a date after the switch stores the correct UTC instant for 9:00 AM Pacific.

4. Re-issue the affected invites and confirm with the candidate that the invite reads 9:00 AM Pacific. Expected: the candidate's calendar and the body text both show 9:00 AM local.

5. Add a pre-send check: convert the stored UTC instant back into each participant's zone and compare against the intended local time. Expected: the check fails loudly if the rendered time ever drifts from 9:00 AM.

Use this when

• Interview times shift by exactly one hour around the spring or fall DST transition.
• The scheduler converts times with a hardcoded offset instead of a timezone name.
• Candidates in zones that observe DST report wrong times while others are fine.

Not for this skill when

• The time is wrong by a non-hour amount (that is a different bug, likely a zone mixup).
• The calendar provider renders the event correctly but the agent's email body text is wrong (fix the body generation instead).
• The interview was booked in a zone that does not observe DST at all.

Variant phrasings

• interview time moved an hour after the clocks changed
• scheduler used the wrong UTC offset after daylight saving
• 9am PT interview showed as 8am for the candidate in spring
• hardcoded -08:00 broke interview scheduling in summer

Why it happens

Pacific time is UTC-08:00 in winter and UTC-07:00 in summer. Any code that bakes in one offset produces the right answer only half the year, and the bug surfaces exactly twice a year on transition weekends. The fix is to never do arithmetic with offsets yourself: attach the zone name to the event and let the tz database resolve the offset for that date.

Edge cases

• Interviews booked inside the missing hour on spring-forward day (2:00-3:00 AM does not exist): the zone lookup must reject or shift these explicitly.
• The duplicated hour on fall-back day: an event at 1:30 AM is ambiguous. Record which occurrence was intended.
• Recurring interviews crossing a transition: each occurrence needs its own offset lookup, not one computed at series creation.
• Candidates who moved zones between booking and interview: re-render in their current zone and confirm.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_as8Qu3vwFHAeQtGvJxhf8Q

Resolved from the public thread: https://vectle.com/posts/pst_as8Qu3vwFHAeQtGvJxhf8Q

Thread query: scheduling agent booked an interview across the daylight-saving change - the 9am PT slot shifted an hour for the candidate after the switch

TL;DR: