Connect Zapier

Zapier connects to Kalender Sync through the MCP Client by Zapier — as a regular action step. That’s the big difference to n8n: you need no AI model in your Zap. The step calls a calendar tool directly, and the response comes back as individually mappable fields you can use in any following step — deterministic, no prompts, no model costs.

The address (MCP server URL) you will enter below is:

https://app.kalender-sync.de/mcp

Prerequisites

• A Kalender Sync account with connected calendars — reading and creating events work on every plan, including Free.
• A Zapier account. The MCP Client by Zapier is a beta integration by Zapier.
• An access key from the app (step 1).

1. Create the access and key in Kalender Sync

In the app, open AI assistant → Connect the assistant and pick Zapier. You pick the calendars one by one and set the detail level per calendar — calendars you don’t share do not exist for Zapier.

Create key gives you your access key (a token starting with ksa_). It is shown only once — copy it straight into the Zapier connection (step 2). Treat it like a password.

2. Set up the connection in Zapier

1. Create a Zap and add MCP Client by Zapier as an action (event: Run Tool).
2. Create a new connection:
   • Server URL: https://app.kalender-sync.de/mcp
   • Requires OAuth: No — important! Zapier’s OAuth path is not supported by us yet; the connection runs on the token.
   • Bearer Token: your ksa_… token from step 1 (the token itself, without a “Bearer” prefix).
3. Once the connection is up, the Configure step lists the available tools: list_calendars, get_availability, search_events and (with write access enabled) create_event, update_event, delete_event. Details for each tool: tool reference.

3. Test and map fields

Pick list_calendars as the tool and run the test. Under Data out you’ll find the result twice:

• as raw text (Response → Text), and
• as structured individual fields (Structured Content → Calendars → …): name, provider, visibility, readability (Readable), writability (Writable), sync health — and most importantly the calendar Id.

You need the calendar id for all other tools: get_availability, search_events and create_event expect it as an argument. The easiest flow is to run list_calendars once in the test, copy the id of your target calendar and enter it in the following steps. For create_event the target calendar must have Writable: true.

Every call shows up in the access log on the AI assistant page.

Zap ideas

Event from a form — no AI involved. Typeform/Google Forms/Jotform trigger → Run Tool: create_event with mapped fields (title from the form, start/end from the chosen slot, your calendar id). The classic “booking into the system” Zap — except the event lands in Google, Outlook or GMX, whichever calendar you shared. (Basic and up, calendar with write access.)

Free slots for new leads. CRM trigger (new lead in HubSpot/Pipedrive) → Run Tool: get_availability for the next working days → a formatter step shapes the free windows → draft email “here are the times I can offer”. Availability spans all shared calendars — no double bookings between work and personal calendars.

Daily agenda to Slack. Schedule by Zapier (weekdays at 7) → Run Tool: search_events for today → formatter → Slack message. No model anywhere: the Structured Content fields map straight into the message.

Focus blocks before deadlines. Trigger from your project tool (say, a new deadline in Asana) → Run Tool: create_event automatically books a focus block ahead of the deadline.

When Zapier, when n8n?

Fixed flows with clear fields (form → event, schedule → agenda) are simpler in Zapier — no model, no prompt maintenance, predictable costs. Free-form questions in natural language (“where do I have two hours in one block this week?”) need an agent — that’s where n8n with an AI agent shines.

Troubleshooting

• Connection won’t establish: first check Requires OAuth: No — with “Yes” the connection currently fails with us. The MCP Client is beta at Zapier; if it still fails with a correct token, a second attempt a few minutes later often helps.
• 401 / “Unauthorized”: token mistyped, expired or revoked. If in doubt, create a fresh token in the app and update the connection.
• A calendar is missing from the result: it isn’t shared with this access — add it in the app under AI assistant → Edit sharing. Changes apply immediately, no new token needed.
• create_event fails: write access is available on every plan, has to be enabled per calendar — and the target calendar id must belong to a calendar with write access.
• Events show no titles: that calendar is set to “busy only” — visibility levels deliberately hide titles there.

Security & control

The same rules as for every assistant access apply to Zapier: you decide per calendar what is visible, every query is logged (never the content of your events), and revoking in Kalender Sync kills the token instantly — regardless of what is stored in Zapier. The token belongs exclusively in the Zapier connection, never in notes, formulas or shared documents.