Comparison
How does Temporal Cortex compare to other Calendar MCP servers?
Most Calendar MCP servers are thin CRUD wrappers — they create, read, update, and delete events, but they lack scheduling safety. Temporal Cortex is the only Calendar MCP server with atomic booking (Two-Phase Commit), deterministic RRULE expansion (Truth Engine), cross-provider availability merging, and temporal context tools. Here is how it compares to every major alternative.
Feature comparison
12 features across 6 Calendar MCP servers. Green checkmarks indicate full support, yellow indicates partial support, and red indicates no support.
| Feature | Temporal Cortex | nspady | rauf543 | MS Agent 365 | taylorwilsdon | Nylas / Cronofy |
|---|---|---|---|---|---|---|
| Atomic booking (2PC) | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ |
| RRULE expansion | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ |
| Multi-provider merge | ✓ | ✗ | ✓ | ✗ | ✗ | Partial |
| Availability computation | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ |
| Temporal context (date/time math) | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ |
| Conflict detection | ✓ | Partial | ✗ | ✗ | ✗ | Partial |
| Open source | ✓ | ✓ | ✓ | ✗ | ✓ | ✗ |
| Agent Skill | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ |
| Truth Engine (deterministic RRULE) | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ |
| CalDAV support | ✓ | ✗ | ✓ | ✗ | ✗ | Partial |
| MCP native | ✓ | ✓ | ✓ | ✗ | ✓ | ✗ |
| Self-hostable | ✓ | ✓ | ✓ | ✗ | ✓ | ✗ |
How Temporal Cortex differs from each alternative
Each Calendar MCP server has different strengths. Here is a breakdown of what each one does and where Temporal Cortex provides additional capabilities.
nspady/google-calendar-mcp
~988 GitHub stars, Google Calendar onlyA popular Google Calendar MCP server (~988 stars) that provides CRUD operations for Google Calendar events. Single-provider, no availability computation or conflict detection beyond basic event overlap checking.
rauf543/calendar-mcp
Multi-provider: Google, Outlook, CalDAVA multi-provider Calendar MCP server supporting Google Calendar, Microsoft Outlook, and CalDAV. Provides basic CRUD operations across providers but lacks availability computation, RRULE expansion, and atomic booking.
MS Agent 365
Preview, Outlook only, not open sourceMicrosoft's agent framework for Outlook and Microsoft 365 calendars. Currently in preview, Outlook-only, and not open source. Tightly integrated with the Microsoft ecosystem but limited to a single provider.
taylorwilsdon/google_workspace_mcp
~1,100 GitHub stars, Google Workspace scopeA Google Workspace MCP server (~1,100 stars) that covers Google Calendar, Drive, Gmail, and other Workspace APIs. Broader than calendar-only but lacks scheduling-specific features like availability computation and atomic booking.
Nylas / Cronofy
Scheduling APIs, experimental MCP wrappersEnterprise scheduling APIs with experimental MCP wrappers. Nylas and Cronofy are established scheduling platforms, but their MCP integrations are not calendar-native — they wrap existing REST APIs rather than providing purpose-built MCP tools.
Why choose Temporal Cortex?
Temporal Cortex is the only Calendar MCP server that combines all three scheduling safety primitives: atomic booking, deterministic recurrence, and cross-provider availability. No other MCP server has all three.
Atomic Booking (2PC)
Lock → verify → write → release. If any step fails, everything rolls back. Zero double-bookings, even with concurrent agents. No other Calendar MCP server has distributed locking.
Truth Engine
Deterministic RRULE expansion written in Rust. Handles DST transitions, BYSETPOS, EXDATE with timezones, and leap years. Not API-dependent — computed locally with zero hallucination.
Availability Merging
Returns "these slots are free across all calendars" — not raw events. Google Calendar + Outlook + iCloud merged into a single availability view. Other servers require the LLM to compute this.
Frequently asked questions
What is the best calendar MCP server?
Temporal Cortex is the most feature-complete Calendar MCP server available. It is the only one with atomic booking via Two-Phase Commit, deterministic RRULE expansion via the Truth Engine, cross-provider availability merging (Google Calendar + Outlook + CalDAV), temporal context tools for date/time math, and an Agent Skill for procedural scheduling knowledge. Other Calendar MCP servers provide basic CRUD operations but lack scheduling safety and availability computation.
How does Temporal Cortex compare to Google Calendar MCP?
Google Calendar MCP servers like nspady/google-calendar-mcp (~988 stars) provide basic CRUD operations for Google Calendar — create, read, update, and delete events. Temporal Cortex goes further with 11 tools across 4 layers: temporal context (date/time resolution, timezone conversion), calendar operations (event listing, free slot finding, RRULE expansion), availability computation (cross-provider merging), and atomic booking (Two-Phase Commit with distributed locking). Temporal Cortex also supports multiple providers (Google, Outlook, CalDAV) while Google Calendar MCP servers are single-provider.
Is Temporal Cortex better than Nylas for AI agents?
Nylas and Cronofy are established scheduling APIs designed for traditional application integrations. Their MCP wrappers are experimental and not calendar-native — they wrap existing REST APIs rather than providing purpose-built MCP tools. Temporal Cortex is built MCP-native from the ground up with 11 tools specifically designed for AI agent workflows, including temporal context, deterministic RRULE expansion, cross-provider availability merging, and atomic booking. For AI agents using the Model Context Protocol, Temporal Cortex provides a more complete and reliable scheduling experience.
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Questions? GitHub Issues are open.