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Calendar access is one of those integrations that changes how “useful” an AI assistant feels day to day. Once OpenClaw can see your schedule it stops guessing and starts answering concrete questions like “when am I free” and “what’s next” with real data.
This guide focuses on OpenClaw calendar integration with Google Calendar because it’s the most common setup, but the same ideas apply to other providers. If you run OpenClaw on a VPS, it’s even easier to keep reminders and automations running 24/7.
If you haven’t installed OpenClaw yet, start with install OpenClaw on Ubuntu and come back after your gateway is stable.
What OpenClaw can do with calendar access
In OpenClaw, calendar access behaves like a skill: it reads and writes events through APIs or feeds then returns results to the chat channel you already use (Discord, WhatsApp, Telegram, Slack). If you’re running multi-channel, the same calendar backend can feed multiple front ends. See OpenClaw multi-channel setup if you want that “one brain, many inboxes” style workflow.
Schedule queries in plain English
Typical prompts become structured queries:
- “What’s on my calendar today”
- “Do I have anything after 3pm Friday”
- “What’s my next meeting”
Behind the scenes, OpenClaw translates the request into a time range then lists events. For Google Calendar API setups this is basically the same operation as calling events.list with timeMin and timeMax.
Event creation and changes
When you say “Schedule a call with Sarah tomorrow at 2pm for 30 minutes” the assistant needs to extract a title, start time, end time, time zone, attendees, location and reminders. That becomes an API request (Google Calendar) or a write action (Microsoft Graph) depending on the provider.
If you want OpenClaw to actually create and move meetings, plan for a short “clarification loop” in your prompts. Humans are vague with dates. “Next Friday” near the end of the week can mean two different Fridays. Good assistants ask back once and then proceed.
Reminders and proactive nudges
Calendar integration also unlocks push style behavior: “message me 10 minutes before my next meeting” or “send a morning briefing at 08:30”. The delivery channel is your choice. On production-style setups most people push these to a private chat with the assistant because it keeps the notifications out of public channels.
If you’re exposing your OpenClaw gateway in any way, read OpenClaw security best practices before you start wiring webhooks. Calendar data contains names, meeting links and sometimes very sensitive notes.
Integration paths you can choose from
There isn’t one single “calendar integration” technique. There are a few and each fits a different level of complexity and privacy.
Option 1: Google Calendar API via OAuth
This is the “proper” Google integration: no password storage, structured access to calendars and events, and the ability to write changes back if you request the right scope. OAuth tokens can be revoked at any time which is exactly what you want for safety.
Option 2: ICS feeds and local parsing
This is the simplest read-only path. Many providers expose an ICS (iCal) subscription URL. OpenClaw can periodically download the feed, parse it locally and answer schedule questions from the cached data. It’s clean for privacy because you can keep it entirely local, but it’s delayed by your sync interval and it can’t create events. For the underlying format, iCalendar is based on RFC 5545.
Option 3: Push updates with watch channels and webhooks
If you want near real-time updates, Google Calendar supports push notifications via watch channels. Google sends notifications to an HTTPS endpoint you control and your server reacts by fetching deltas from the API. The Events watch method also supports a time-to-live value and the docs state the default TTL is 604800 seconds (7 days).
Option 4: Microsoft 365 and other providers
For Microsoft calendars you usually use Microsoft Graph with OAuth in the same general pattern. The mechanics are similar: register an app, grant calendar scopes, store refreshable tokens, call list and create endpoints.
Google Calendar OAuth setup for OpenClaw
If you already set up OAuth for Gmail, you can usually reuse the same Google Cloud project and just enable the Calendar API and add calendar scopes. The consent screen and OAuth client are the same building blocks.
Create or reuse a Google Cloud project
Create a dedicated project for OpenClaw integrations so you can see and control what has access. Keeping it separate also makes it easier to revoke everything in one go if you ever need to.
Enable Google Calendar API
In Google Cloud Console, enable “Google Calendar API” under APIs & Services. If you’re doing Gmail too, you’ll likely enable both in the same project.
Pick OAuth client type
Desktop app client for CLI flows
This is common when you run OpenClaw on a VPS and you want a device-code or local redirect flow that stores tokens on disk. It’s also easier to rotate because it’s basically “re-login then replace token file”.
Web application client for server redirects
This is for setups where your server hosts a callback URL. It can be cleaner if you’re building a full integration service alongside OpenClaw but it adds HTTPS and reverse proxy requirements.
Choose the minimum OAuth scopes
Scopes are your permission boundary. Request less and you reduce risk.
https://www.googleapis.com/auth/calendar.readonlyfor read-only calendar datahttps://www.googleapis.com/auth/calendar.eventsto create and modify eventshttps://www.googleapis.com/auth/calendar.events.readonlyfor events read-only without full calendar access
A boring but real suggestion: start with read-only. Run it for a week. Then add write access only if you’re actually going to use event creation and rescheduling.
Token storage and process isolation
Treat OAuth tokens like passwords. Store them with restrictive filesystem permissions and keep them out of git, backups and screenshots. If your VPS runs multiple services, consider a dedicated Linux user for OpenClaw and keep tokens only readable by that user.
If you’re already running OpenClaw under systemd, the same approach you used for keeping secrets in an EnvironmentFile applies here too. If you want a production-style baseline, pair this with host OpenClaw securely on a VPS.
How OpenClaw turns a chat request into calendar API calls
This part is what makes the integration feel “smart”. The calendar API is dumb. It needs exact values. Your chat messages are not exact.
Time parsing and time zones
Calendar queries are only reliable when you lock time zones. Store a default time zone in your OpenClaw config or in your assistant’s memory. If you travel a lot, you’ll want the assistant to ask “local time where” instead of assuming.
When listing events, most API calls accept ISO 8601 timestamps. When creating events, you’ll be sending start and end times with time zone metadata. If a model returns “tomorrow afternoon” you either map it to a default window or ask a follow-up question. Both are fine. Guessing silently is how meetings get booked wrong.
Recurring events and why they are annoying
Recurrence rules look simple until they aren’t. Google Calendar APIs can expand recurring events for listing. ICS feeds also support recurrence rules which means your parser needs to expand them too. If you pick the ICS route, make sure your parser handles RRULE expansion or your “what’s on my calendar this week” answers will be wrong for repeating meetings.
Free time calculations
Finding availability is not the same as listing events. You also need:
- working hours
- buffer rules (like 10 minutes between meetings)
- multiple calendars merged into one view
Once you have that, free time is just subtracting busy blocks from the allowed day range. The tricky bit is edge cases: all-day events, travel blocks, tentative meetings and calendars that overlap with different time zones.
ICS feed integration for read-only calendar access
If you don’t want OAuth, ICS is your friend. It’s also a solid option for shared calendars where you only need read access.
How ICS sync usually works
The safe pattern is a periodic download job that caches the calendar locally:
- download to a temp file
- verify it looks like a calendar payload
- swap it into place
- keep the previous version as backup
OpenClaw then calls a local script that reads the cached ICS files and returns normalized JSON that the assistant can format nicely.
Pros and limits
ICS is low complexity and provider-agnostic. The big limit is write access. You can’t reliably create events with ICS. If “book the meeting” is part of your plan, go OAuth.
Real-time calendar updates with Google push notifications
Polling every few minutes is fine for personal use. It’s also wasteful. Google’s push notifications exist for a reason.
How Events watch works
In Google Calendar API, the Events watch endpoint lets you register an HTTPS address that will receive notifications. The request body includes a channel id, optional token, delivery type and an address. You can also set a TTL in seconds and Google documents the default as 604800 seconds.
What the webhook receives
Push notifications are not full event payloads. They are “something changed” signals. The push guide documents headers like X-Goog-Resource-Id and resource state values used to decide what to do next. The normal next step is a delta sync: fetch what changed since your last token or timestamp then process it.
Renewing watch channels
Watch channels expire. So you plan for renewal like it’s part of the system, not an edge case. A simple approach is a daily job that checks expiration and renews early. If you miss it you don’t lose data, you just fall back to polling until you re-register.
Idempotency and duplicate notifications
Push systems can deliver duplicates. Treat every notification as “maybe repeated” and dedupe by event ID plus updated timestamp. If you’re sending chat alerts, dedupe before you notify or you’ll spam yourself during calendar edits.
Workflows that actually feel useful
A calendar integration is only as good as the workflows you build on top of it. Here are patterns that people keep because they save time.
Morning briefing to chat
A scheduled job queries “today” then sends a compact message:
- first meeting time
- gaps longer than 60 minutes
- anything off-site or with a location
If you like the assistant to remember preferences like “no meetings before 10” or “always add 15 min buffer” store that in memory. You can see how OpenClaw approaches memory in OpenClaw memory explained.
On-demand availability checks
In practice, the best UX is two-step:
- you ask “when am I free for 45 minutes this week”
- OpenClaw returns 3 to 8 candidate slots and asks which one to book
That second step matters because it prevents accidental bookings and it gives you a chance to choose based on context that the calendar does not show.
Time blocking for focused work
If you’re prone to “accidental meeting creep”, time blocks help. The assistant can create “Focus block” events to reserve space then you decide if you respect them. It’s not magic but it works when you actually follow it.
Combined email and calendar workflows
This is where OpenClaw starts feeling like a real assistant. Example: you get an email proposing a meeting time, OpenClaw extracts candidate times, checks calendar free slots and then drafts a reply with alternatives if needed. If you’re building the email side too, keep the security model tight since email and calendar together increases risk surface.
Security and privacy notes that matter in real setups
Calendar data is personal and business sensitive. Treat it like email.
Least privilege and separate accounts
If you only want read access, stick to read scopes. If you want write, consider using a dedicated assistant Google account and share selected calendars to it instead of granting full control to your primary account. It’s a clean containment model and it’s easy to revoke.
Protect webhook endpoints
If you expose an endpoint for Google push notifications, put it behind HTTPS and verify requests. Do not log full payloads. Rate-limit requests at the proxy. If you do not already have a hardened gateway setup, follow OpenClaw security best practices before you open more doors.
Keep logs boring
It’s tempting to log everything while debugging. Avoid logging attendee emails, meeting links or descriptions. Log IDs and timestamps then fetch details when you need them.
Operations on a VPS
Calendar automations want uptime. Laptops sleep. Home networks reset. A VPS stays on. That’s why a VPS is a good place to host OpenClaw if you rely on calendar reminders.
Run OpenClaw under systemd so it restarts automatically. Keep helper processes (like webhook receivers) as their own services too. If you’re already doing this for other integrations, you’ll recognize the pattern from OpenClaw WhatsApp production setup.
