ProvelyProve that the guests the person named are on the invitation. The stored attendee list holds the addresses that the person named. It does not prove that Google mailed a guest, or that a guest accepted.
| Fact | Value |
|---|---|
| Contract id | google_calendar.event.guests_invited |
| Version | 1.0.0 |
| Hash | c196fc8c385fd780 |
| Completion level | guests_invited |
| Publisher | Built and signed by Provely. |
| Certification | Provisional |
| Skill | Google Calendar API 0.1.0 |
| Valid for provider API versions | v3.20260826 |
What is the intent?
Put the meeting on the calendar and invite the named people.
What is the subject and the action?
| Member | Value |
|---|---|
| Subject type | google_calendar.event |
| Subject identity | event_id = $action.result.id |
| Canonical effect | calendar.event_create |
| Provider operation | POST /calendar/v3/calendars/{calendarId}/events |
| Idempotency | none, retry is not safe |
How does the evidence correlate with this operation?
| Strategy | Assurance | Keys | Required |
|---|---|---|---|
resource_id | strong | event_id from $action.result.id | no |
resource_id | weak | calendar_id from $input.calendar_id | no |
fingerprint | weak | calendar_id from $input.calendar_id; summary from $input.summary | no |
Which evidence does the contract require?
Minimum evidence level E2. An independent channel is required. Minimum channels: 1.
| Channel | Level | Independence | Verifier | Description |
|---|---|---|---|---|
event_readback | E2 | provider readback | http | Read the new event from the provider. A condition path is $observed.event_readback.start.dateTime. Google returns the instant in the time zone of the calendar, so a condition compares instants and never two strings. |
calendar_change_events | E3 | provider event | webhook | The notifications of a channel that watches the events collection of the calendar, since the operation started. The webhook verifier returns {events, count, latest, earliest, types, duplicates_dropped}. The body is empty, so a count names no event. |
Which conditions must all hold for VERIFIED?
| Condition | Meaning | Path | Operator | Expected | Evidence |
|---|---|---|---|---|---|
event_present | The provider holds the event with the identifier of the insert answer. | $observed.event_readback.id | eq | $action.result.id | event_readback |
event_title_matches | The title of the event equals the title that the person named. | $observed.event_readback.summary | eq | $input.summary | event_readback |
event_status_confirmed | The status of the event is confirmed. The published description names that value the default status. | $observed.event_readback.status | eq | confirmed | event_readback |
event_starts_at_the_requested_instant | The stored start names the instant that the person named. | — | all_of | The rows below state the members. | event_readback |
event_starts_at_the_requested_instant_not_before | The stored instant is not before the instant that the person named. | $observed.event_readback.start.dateTime | time_after | $input.start_time | event_readback |
event_starts_at_the_requested_instant_not_after | The stored instant is not after the instant that the person named. | $observed.event_readback.start.dateTime | time_before | $input.start_time | event_readback |
event_ends_at_the_requested_instant | The stored end names the instant that the person named. | — | all_of | The rows below state the members. | event_readback |
event_ends_at_the_requested_instant_not_before | The stored instant is not before the instant that the person named. | $observed.event_readback.end.dateTime | time_after | $input.end_time | event_readback |
event_ends_at_the_requested_instant_not_after | The stored instant is not after the instant that the person named. | $observed.event_readback.end.dateTime | time_before | $input.end_time | event_readback |
event_created_in_window | The provider created the event after the operation started. | $observed.event_readback.created | time_after | $operation.created_at | event_readback |
calendar_changed | At least one notification says that the events collection of the calendar changed since the operation started. The published page states that a small percentage of messages drop, so a lost message leaves this level unproven and never verified. | $observed.calendar_change_events.count | gte | 1 | calendar_change_events |
every_requested_guest_is_an_attendee | The stored attendee list holds the addresses that the person named. No published sentence states the order of the list, so a reorder leaves this level unproven and never verified. | $observed.event_readback | jsonpath | $input.guest_emails | event_readback |
attendee_count_matches | The stored attendee list holds exactly as many entries as the person named. A stranger on the list therefore fails this condition. | $observed.event_readback.attendees | array_length | $input.guest_count | event_readback |
Which conditions give CONTRADICTED?
| Condition | Class | Reason | Path | Operator | Expected |
|---|---|---|---|---|---|
event_title_differs | wrong subject | The event carries a different title than the person named. | $observed.event_readback.summary | ne | $input.summary |
event_starts_too_early | wrong subject | The event starts before the instant that the person named. | $observed.event_readback.start.dateTime | time_before | $input.start_time |
event_starts_too_late | wrong subject | The event starts after the instant that the person named. | $observed.event_readback.start.dateTime | time_after | $input.start_time |
event_ends_too_early | wrong subject | The event ends before the instant that the person named. | $observed.event_readback.end.dateTime | time_before | $input.end_time |
event_ends_too_late | wrong subject | The event ends after the instant that the person named. | $observed.event_readback.end.dateTime | time_after | $input.end_time |
event_predates_operation | pre existing state | The event is older than the operation. It proves nothing about this operation. | $observed.event_readback.created | time_before | $operation.created_at |
duplicate_calendar_change | duplicate side effect | The calendar changed more than once since the operation started. A second insert mails every guest a second time. Do not retry. | $observed.calendar_change_events.count | gt | 1 |
attendee_list_truncated | partial completion | The read returned a short attendee list. The verifier cannot see every guest. Ask a person. | $observed.event_readback.attendeesOmitted | eq | true |
Which observed states map to a verdict before completion?
| Rule | Match | Verdict | Reason |
|---|---|---|---|
event_is_cancelled | $observed.event_readback.status eq "cancelled" | CONTRADICTED | The event is cancelled. The published description states that a cancelled event is a deleted event. The API reports no failure for this end. |
event_is_a_locked_copy | $observed.event_readback.locked eq true | CONTRADICTED | The event is a locked copy. The published description states that nobody can change its title, its start or its end. Ask a person. |
event_is_all_day | $observed.event_readback.start.date exists undefined | CONTRADICTED | The agent created an all-day event. This level promises a timed event, and an all-day event carries no dateTime, so no later read can prove the instant. |
the_wrong_people_are_on_the_invitation | ($observed.event_readback.attendees exists undefined) and (not ($observed.event_readback jsonpath "$input.guest_emails")) | CONTRADICTED | The invitation names other people than the person asked for. A guest who should not see the meeting can see it, or a guest who should see it cannot. Ask a person. |
How long does the runtime observe?
| Timing member | Value |
|---|---|
| Initial delay | 1000 ms |
| Poll interval | 5000 ms |
| Backoff | exponential factor 2, max 60000 ms |
| Maximum attempts | 40 |
| Timeout | 900000 ms |
| Stale read window | 20000 ms |
| On timeout | UNVERIFIABLE (evidence_unavailable_before_timeout), escalated to a person |
Where do these rules come from?
google_calendar.openapi#/components/schemas/Event/properties/attendees: google_calendar.openapi, retrieved 2026-09-09google_calendar.openapi#/components/schemas/EventAttendee/properties/email: google_calendar.openapi, retrieved 2026-09-09google_calendar.docs.events#create-an-event-and-invite-guests/a-created-event-reaches-the-calendar-of-every-attendee: google_calendar.docs.events, retrieved 2026-09-09google_calendar.docs.events#create-an-event-and-invite-guests/the-mail-is-a-separate-promise-and-sendupdates-decides-it: google_calendar.docs.events, retrieved 2026-09-09google_calendar.openapi#/components/schemas/Event/properties/id: google_calendar.openapi, retrieved 2026-09-09google_calendar.openapi#/paths/~1calendar~1v3~1calendars~1{calendarId}~1events~1{eventId}/get/responses/200: google_calendar.openapi, retrieved 2026-09-09google_calendar.openapi#/components/schemas/Event/properties/summary: google_calendar.openapi, retrieved 2026-09-09google_calendar.openapi#/paths/~1calendar~1v3~1calendars~1{calendarId}~1events/post/requestBody: google_calendar.openapi, retrieved 2026-09-09google_calendar.openapi#/components/schemas/Event/properties/status: google_calendar.openapi, retrieved 2026-09-09google_calendar.docs.times#events-times-and-the-change-of-a-time/the-status-of-an-event: google_calendar.docs.times, retrieved 2026-09-09google_calendar.openapi#/components/schemas/Event/properties/created: google_calendar.openapi, retrieved 2026-09-09google_calendar.docs.times#events-times-and-the-change-of-a-time/the-two-times-that-calendar-publishes-about-an-event: google_calendar.docs.times, retrieved 2026-09-09google_calendar.events#/events/calendar.events.exists: google_calendar.events, retrieved 2026-09-09google_calendar.docs.push#push-notifications/one-resource-state-covers-three-different-changes: google_calendar.docs.push, retrieved 2026-09-09google_calendar.openapi#/paths/~1calendar~1v3~1calendars~1{calendarId}~1events~1watch/post: google_calendar.openapi, retrieved 2026-09-09google_calendar.docs.push#push-notifications/what-the-page-refuses-to-promise: google_calendar.docs.push, retrieved 2026-09-09google_calendar.docs.events#create-an-event-and-invite-guests/an-attendee-needs-an-address: google_calendar.docs.events, retrieved 2026-09-09google_calendar.openapi#/components/schemas/EventAttendee: google_calendar.openapi, retrieved 2026-09-09
Can google_calendar.event.guests_invited return VERIFIED from the action response alone?
No. The minimum evidence level is E2. The action response is E1. The completion conditions read event_readback and calendar_change_events.
What happens after the timeout?
The verdict is UNVERIFIABLE with the reason evidence_unavailable_before_timeout. The operation goes to a person for review.