Astrocal
Connects Claude to Astrocal's scheduling API so your assistant can book, cancel, and reschedule meetings through conversation. Exposes eight tools including availability checks, booking creation, waitlist management, and event type listing. Works against real calendar data synced from Google Calendar, Microsoft 365, or CalDAV. Handles paid bookings through Stripe Connect if needed. Ships with sandbox mode for testing without sending emails or creating actual events. You'd reach for this if you want scheduling capabilities in Claude Desktop or any MCP client without building calendar integration yourself. Requires an Astrocal API key, then it's a single config block to enable all the scheduling tools.
- tools
- 8
- auth
- Secret needed
- transport
- STDIO, HTTP
- env vars
- 3
- last updated
- Jun 24, 2026
Tools
8 toolsPublic tool metadata for what this MCP can expose to an agent.
check_availabilityCheck available time slots for booking.
Check available time slots for booking.
No parameter schema in public metadata yet.
create_bookingBook a meeting at a specific time.
Book a meeting at a specific time.
No parameter schema in public metadata yet.
cancel_bookingCancel an existing booking. The invitee receives a cancellation email automatically.
Cancel an existing booking. The invitee receives a cancellation email automatically.
No parameter schema in public metadata yet.
reschedule_bookingReschedule a booking to a new time. Check availability first.
Reschedule a booking to a new time. Check availability first.
No parameter schema in public metadata yet.
list_bookingsList bookings with optional filters.
List bookings with optional filters.
No parameter schema in public metadata yet.
list_event_typesList available event types that can be booked. No input required.
List available event types that can be booked. No input required.
No parameter schema in public metadata yet.
join_waitlistJoin the waitlist when all slots are full.
Join the waitlist when all slots are full.
No parameter schema in public metadata yet.
check_waitlistCheck your position on a waitlist.
Check your position on a waitlist.
No parameter schema in public metadata yet.
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ASTROCAL_API_KEY*secretYour Astrocal API key (create one at https://astrocal.dev/dashboard/connect)
ASTROCAL_API_URLCustom API base URL (defaults to https://api.astrocal.dev)
ASTROCAL_DEFAULT_EVENT_TYPE_IDDefault event type ID when not specified in tool calls
Readme
@astrocal/mcp-server
Give your AI agents the power to schedule meetings. The official Model Context Protocol server for Astrocal — the API-first scheduling platform built for developers and AI agents.
Works with Claude Desktop, Cursor, Windsurf, and any MCP-compatible client. Your AI assistant can check availability, book meetings, cancel, reschedule, and manage waitlists — all through natural conversation.
Get your API key | Documentation | API Reference
Why Astrocal for AI Agents?
Details
- Repository
- github.com/astrocal-dev/mcp-server
- Website
- astrocal.dev
- Package
@astrocal/mcp-server- Transport
- STDIO, HTTP
- Auth
- Required
- Registry
- MCP registry, active