Change one occurrence of a repeating event

calendar.event.update_occurrence

POST/api/v1/households/{household_id}/commands/calendar.event.update_occurrence

Command
Rigel runs it
Applies offline

Changes the title, notes, place or time of a single occurrence, named by occurrence_start (its original start from calendar.occurrence.list). Giving only starts_at (or start_date) moves it and keeps its length. Changing a cancelled occurrence brings it back. Errors: event_not_found, event_owned_by_app, occurrence_not_found (the event doesn't repeat, or doesn't happen then), invalid_time_range.

Parameters#

Change one occurrence of a repeating event: parameters
Field	Description
`household_id`pathstringrequired	The household's ID.
`Idempotency-Key`headerstringoptional	The command's ID. Reuse it when retrying the same command.

Request body#

JSON, as application/json.

Change one occurrence of a repeating event: request body fields
Field	Description
`event_id`stringrequired	A calendar event ID, such as evt_01JC0000000000000000000000.
`occurrence_start`stringrequired	Which occurrence, by its original start in the event's zone: 2026-11-14T09:00 for a timed event, 2026-11-14 for an all-day one. Use the occurrence_start that `calendar.occurrence.list` gave.
`title`stringoptional	The event's title, as written, 1–200 characters. 1 to 200 characters
`description`stringoptional	Notes about the event, as written, up to 8,000 characters. at most 8,000 characters
`location`stringoptional	Where it is, as written, up to 500 characters. at most 500 characters
`starts_at`stringoptional	When a timed event starts. ISO 8601: with an offset it's that instant, without one it's wall-clock time in time_zone, so 2026-11-11T15:30 means 3:30pm there.
`ends_at`stringoptional	When a timed event ends, in the same form as starts_at.
`start_date`stringoptional	The first day of an all-day event, YYYY-MM-DD.
`end_date`stringoptional	The last day of an all-day event, YYYY-MM-DD, inclusive. The same as start_date for a one-day event.

Response#

200 The command was applied.

Change one occurrence of a repeating event: response fields
Field	Description
`result`objectrequired	What the command returned, such as the IDs it created.
`version`integerrequired	The household version after the command.

Errors#

Every error has the same envelope: error.code, error.message, error.details, error.recovery and error.request_id.

Change one occurrence of a repeating event: errors
Status	Code	When
`400`	`validation_failed`	A field is missing, misspelled or out of range. details.fields lists each problem.
`401`	`unauthenticated`	The request has no valid session.
`404`	`event_not_found`	The event doesn't exist in this household. The event must exist.
`404`	`occurrence_not_found`	The event doesn't repeat, or doesn't happen then. A day the rule doesn't reach isn't an occurrence. An event that doesn't repeat has no separate occurrences. The key must have the event's form.
`404`	`not_found`	The household doesn't exist, or you aren't a member of it.
`409`	`event_owned_by_app`	An event another app owns is refused.
`409`	`invalid_time_range`	An all-day occurrence can't be given a start time. A timed occurrence can't be given dates. An occurrence can't end before it starts.
`409`	`idempotency_key_reused`	The Idempotency-Key was already used for a different command.

Examples#

These are real. Each scenario is one of the command's test cases, run on a household when this site was built, and the response is what the API returned.

Retitling one Saturday adds an exception

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "title": "Swim meet",
  "location": "County pool"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15T09:00:00",
    title: "Swim meet",
    location: "County pool",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "title": "Swim meet",
  "location": "County pool"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01K9D9S2R00CSVYCQ1REVW3JAE

{
  "result": {},
  "version": 1
}

Moving one Saturday's start keeps its length

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00",
  "starts_at": "2025-11-15T11:00"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15T09:00",
    starts_at: "2025-11-15T11:00",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00",
  "starts_at": "2025-11-15T11:00"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0TXNGWWATEZSEFQ62

{
  "result": {},
  "version": 1
}

Giving only ends_at changes that occurrence's length

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "ends_at": "2025-11-15T11:30"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15T09:00:00",
    ends_at: "2025-11-15T11:30",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "ends_at": "2025-11-15T11:30"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01K9D9S2R092SJFSTZJVAK588Z

{
  "result": {},
  "version": 1
}

Changing an occurrence again updates its exception, and brings a cancelled one back

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "description": "Bring goggles"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15T09:00:00",
    description: "Bring goggles",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "description": "Bring goggles"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01K9D9S2R046MT6BDZ4MZYSZPA

{
  "result": {},
  "version": 1
}

An extra date can be changed too

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-12-23T09:00:00",
  "title": "Holiday swim"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-12-23T09:00:00",
    title: "Holiday swim",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-12-23T09:00:00",
  "title": "Holiday swim"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0X95GZC5KDHKYV2PD

{
  "result": {},
  "version": 1
}

An all-day occurrence takes dates

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000C",
  "occurrence_start": "2026-11-14",
  "start_date": "2026-11-21"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000C",
    occurrence_start: "2026-11-14",
    start_date: "2026-11-21",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000C",
  "occurrence_start": "2026-11-14",
  "start_date": "2026-11-21"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01K9D9S2R04PA5KTZ0EP0810Y7

{
  "result": {},
  "version": 1
}

A moved occurrence shows up on a busy-only calendar without its details

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "title": "Secret",
  "starts_at": "2025-11-15T13:00"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15T09:00:00",
    title: "Secret",
    starts_at: "2025-11-15T13:00",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "title": "Secret",
  "starts_at": "2025-11-15T13:00"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0VYR2ED5CYZX3W7ZT

{
  "result": {},
  "version": 1
}

A day the rule doesn't reach isn't an occurrence

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-16T09:00",
  "title": "x"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-16T09:00",
    title: "x",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-16T09:00",
  "title": "x"
}

Response, 404

HTTP/1.1 404 Not Found
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0NG4YSCQHVZ6HDZBF

{
  "error": {
    "code": "occurrence_not_found",
    "message": "The event doesn't happen at 2025-11-16T09:00:00. No changes were applied.",
    "details": {
      "occurrence_start": "2025-11-16T09:00:00"
    },
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R0NG4YSCQHVZ6HDZBF"
  }
}

An event that doesn't repeat has no separate occurrences

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000B",
  "occurrence_start": "2025-11-11T15:30",
  "title": "x"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000B",
    occurrence_start: "2025-11-11T15:30",
    title: "x",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000B",
  "occurrence_start": "2025-11-11T15:30",
  "title": "x"
}

Response, 404

HTTP/1.1 404 Not Found
Content-Type: application/json
X-Request-Id: req_01K9D9S2R02J2BCXW82F3B11JN

{
  "error": {
    "code": "occurrence_not_found",
    "message": "That event doesn't repeat, so it has no separate occurrences. Change the event itself. No changes were applied.",
    "details": {
      "occurrence_start": "2025-11-11T15:30:00"
    },
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R02J2BCXW82F3B11JN"
  }
}

The key must have the event's form

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15",
  "title": "x"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15",
    title: "x",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15",
  "title": "x"
}

Response, 404

HTTP/1.1 404 Not Found
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0WRNV37NES1DQEMJ6

{
  "error": {
    "code": "occurrence_not_found",
    "message": "This event has a start time, so name the occurrence by its date and time, such as 2026-11-14T09:00. No changes were applied.",
    "details": {
      "occurrence_start": "2025-11-15"
    },
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R0WRNV37NES1DQEMJ6"
  }
}

An all-day occurrence can't be given a start time

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000C",
  "occurrence_start": "2026-11-14",
  "starts_at": "2026-11-14T10:00"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000C",
    occurrence_start: "2026-11-14",
    starts_at: "2026-11-14T10:00",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000C",
  "occurrence_start": "2026-11-14",
  "starts_at": "2026-11-14T10:00"
}

Response, 409

HTTP/1.1 409 Conflict
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0745TDBBGZHXFT5Z1

{
  "error": {
    "code": "invalid_time_range",
    "message": "This is an all-day event, so give start_date and end_date. No changes were applied.",
    "details": {},
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R0745TDBBGZHXFT5Z1"
  }
}

A timed occurrence can't be given dates

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "start_date": "2025-11-15"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15T09:00:00",
    start_date: "2025-11-15",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "start_date": "2025-11-15"
}

Response, 409

HTTP/1.1 409 Conflict
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0DWDDJP8J70EP2H0S

{
  "error": {
    "code": "invalid_time_range",
    "message": "This event has a start time, so give starts_at and ends_at. No changes were applied.",
    "details": {},
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R0DWDDJP8J70EP2H0S"
  }
}

An occurrence can't end before it starts

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "starts_at": "2025-11-15T09:00",
  "ends_at": "2025-11-15T08:00"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000A",
    occurrence_start: "2025-11-15T09:00:00",
    starts_at: "2025-11-15T09:00",
    ends_at: "2025-11-15T08:00",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000A",
  "occurrence_start": "2025-11-15T09:00:00",
  "starts_at": "2025-11-15T09:00",
  "ends_at": "2025-11-15T08:00"
}

Response, 409

HTTP/1.1 409 Conflict
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0TNACQ1BVWNP7CYXM

{
  "error": {
    "code": "invalid_time_range",
    "message": "An event can't end before it starts. No changes were applied.",
    "details": {},
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R0TNACQ1BVWNP7CYXM"
  }
}

An event another app owns is refused

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000D",
  "occurrence_start": "2025-11-20T09:00",
  "title": "x"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000D",
    occurrence_start: "2025-11-20T09:00",
    title: "x",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000D",
  "occurrence_start": "2025-11-20T09:00",
  "title": "x"
}

Response, 409

HTTP/1.1 409 Conflict
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0EG3FN4X6K0BP24CE

{
  "error": {
    "code": "event_owned_by_app",
    "message": "Maintenance manages this event. Change it there. No changes were applied.",
    "details": {
      "app": "maintenance"
    },
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R0EG3FN4X6K0BP24CE"
  }
}

The event must exist

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA' \
  -d '{
  "event_id": "evt_01JC000000000000000000000Z",
  "occurrence_start": "2025-11-15T09:00:00",
  "title": "x"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01JC4N0000AAAAAAAAAAAAAAAA",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01JC000000000000000000000Z",
    occurrence_start: "2025-11-15T09:00:00",
    title: "x",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01K9BKKP003AHRZ6DMV29GQY5C/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01JC4N0000AAAAAAAAAAAAAAAA

{
  "event_id": "evt_01JC000000000000000000000Z",
  "occurrence_start": "2025-11-15T09:00:00",
  "title": "x"
}

Response, 404

HTTP/1.1 404 Not Found
Content-Type: application/json
X-Request-Id: req_01K9D9S2R0D5VV94J0AA8V1T6X

{
  "error": {
    "code": "event_not_found",
    "message": "That event isn't on the calendar any more. No changes were applied.",
    "details": {
      "event_id": "evt_01JC000000000000000000000Z"
    },
    "recovery": "Read the current state, then send a command that fits it.",
    "request_id": "req_01K9D9S2R0D5VV94J0AA8V1T6X"
  }
}

Move one occurrence

occurrence_start is the occurrence's original start. Only starts_at moves it and keeps its length.

Request, curl

curl -X POST 'https://rigel.house/api/v1/households/hh_01M6V9CS6GGVFCY7NAS8ZTQV95/commands/calendar.event.update_occurrence' \
  -H "Cookie: rigel_session=$RIGEL_SESSION" \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: cmd_01M6V9CSJVQYDH0EK00FEW6BMJ' \
  -d '{
  "event_id": "evt_01M6V9CSHPG77MMGGKHAEJQ484",
  "occurrence_start": "2026-11-17T17:00",
  "starts_at": "2026-11-17T17:30"
}'

Request, TypeScript

const response = await fetch("https://rigel.house/api/v1/households/hh_01M6V9CS6GGVFCY7NAS8ZTQV95/commands/calendar.event.update_occurrence", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Idempotency-Key": "cmd_01M6V9CSJVQYDH0EK00FEW6BMJ",
    Cookie: `rigel_session=${process.env.RIGEL_SESSION}`,
  },
  body: JSON.stringify({
    event_id: "evt_01M6V9CSHPG77MMGGKHAEJQ484",
    occurrence_start: "2026-11-17T17:00",
    starts_at: "2026-11-17T17:30",
  }),
});
const data = await response.json();

Request, HTTP

POST /api/v1/households/hh_01M6V9CS6GGVFCY7NAS8ZTQV95/commands/calendar.event.update_occurrence HTTP/1.1
Host: rigel.house
Cookie: rigel_session=<your session>
Content-Type: application/json
Idempotency-Key: cmd_01M6V9CSJVQYDH0EK00FEW6BMJ

{
  "event_id": "evt_01M6V9CSHPG77MMGGKHAEJQ484",
  "occurrence_start": "2026-11-17T17:00",
  "starts_at": "2026-11-17T17:30"
}

Response, 200

HTTP/1.1 200 OK
Content-Type: application/json
X-Request-Id: req_01M6V9CSJV8VWMY2RNWCK6FM2Q

{
  "result": {},
  "version": 94
}

For Rigel#

Rigel's tool for this command is calendar_event_update_occurrence. Rigel runs this on its own, then says what it did. The agent guide has the rest.