Plain-text Google Calendar event tool

What it is

This n8n workflow is a tool for an AI agent, and another workflow has to call it. The caller passes a sentence as query, such as lunch with Sam next Tuesday at 1pm. Four nodes run in a line. The first asks gpt-4o for an event name, a start time and an end time. It uses n8n’s own clock to settle words like next Tuesday and adds half an hour when no end is given. A Google Calendar node creates the event. The last node sets response to the word done.

Who it suits

People who give an n8n agent a calendar, so that someone can say a dentist visit on Friday at 9 in a chat or by voice and see the event appear. A scheduled flow that turns a line of text, such as an email subject or a form message, into an event can call it too.

Where to use it

Any n8n that can reach Google Calendar and OpenAI will do, on n8n Cloud or on a server of your own. Nothing happens until something calls it. An agent’s Call n8n Workflow Tool node is the natural caller, behind a chat or a Telegram bot, because the person’s own sentence goes straight in. Any other flow can use an Execute Workflow node.

Setup

Get it saves a zip with workflow.json and Mindket’s setup notes in your downloads folder. Have two things ready: an OpenAI key, and a Google account whose calendar n8n may write to.

1. In n8n, create a workflow, open its menu, choose Import from File and pick workflow.json.
2. Add an OpenAI credential and select it in the OpenAI node.
3. Add a Google Calendar OAuth2 credential and select it in Google Calendar.
4. In the same node, pick the calendar to write to in the Calendar field, which holds YOUR_CALENDAR_ID.
5. Save, then add the node that runs it to the calling workflow. For an agent, give the tool one line saying what it does, because the agent reads that line to decide when to use it.

The caller passes one text field and gets one back. The sentence arrives as query, and the word done leaves as response:

in:  { "query": "Lunch with Sam next Tuesday at 1pm" }
out: { "response": "done" }

How to use it

Say what you want to book, in a sentence with a day and a time. The agent hands it over, the tool creates the event, and the agent confirms. The reply is only the word done, so the agent has no time or link to read back. To change that, put the event’s name and times into response in Edit Fields. To try it without an agent, pin an item with a query field on Execute Workflow Trigger and run it.

Example

On Monday 2 November 2026 the caller passes “Dentist on Friday at 9am”. gpt-4o is asked for three fields, and with no end given it adds half an hour. It might return:

{
  "Event Name": "Dentist",
  "Start Time": "2026-11-06T09:00:00",
  "End Time": "2026-11-06T09:30:00"
}

For newcomers and experts

If you are new. A sub-workflow is an ordinary workflow that starts from Execute Workflow Trigger and waits to be called. Run it on its own first. Then open your Google Calendar and check that the event is there, at the time you meant.

For experts. The model writes the times as text and Google Calendar reads them as they come. A format it cannot read may stop the run with an error, so the agent sees a failed call, not done. Add your usual meeting length or a default hour to the OpenAI message. A description, a place or guests go under Additional Fields in Google Calendar.

Good to know

Each sentence costs one OpenAI call, and the tool writes to your calendar with nothing to undo it.

• Repeats: nothing checks for a clash or a duplicate, so the same sentence sent twice makes two events
• Time zone: the model settles words like Friday from n8n’s clock, so check the time zone in the workflow’s settings
• Who can write: anyone who can talk to the agent can add events to this calendar, so keep it behind people you trust
• Credentials: the JSON holds none, and nothing from its author’s account