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Head to head · Calendar read · October 2026 research run

Cal.com API v2 + MCP vs Google Calendar API

Google Calendar API has a score of 79.5 (A) against Cal.com API v2 + MCP's 57.5 (C). Both do calendar read. The largest gap is agent ergonomics, 41 points.

Cal.com API v2 + MCPCal.com · HTTP API C57.5/100#292 of 452 Google Calendar APIGoogle · HTTP API A79.5/100#8 of 452

Which one, for what

Pick Cal.com API v2 + MCP for

No category where it leads by five points or more.

Pick Google Calendar API for

  • reliability (+30)
  • schema & documentation (+7)
  • agent ergonomics (+41)
  • security & auth (+26)
  • payments & pricing (+5)
  • maintenance & community (+37)

Score by category

CategoryWeight this runCal.com API v2 + MCPGoogle Calendar APIEdge
Reliability16%206090Google Calendar API +30
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27683Google Calendar API +7
Agent ergonomics13%16.25091Google Calendar API +41
Security & auth14%17.55682Google Calendar API +26
Payments & pricing10%12.53035Google Calendar API +5
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.85087Google Calendar API +37
Transparency & trust7%8.88179Cal.com API v2 + MCP +2
Negative events≤1500
Total57.5 · C79.5 · A

Facts side by side

FactCal.com API v2 + MCPGoogle Calendar API
KindHTTP APIHTTP API
VendorCal.comGoogle
Hosted endpointhttps://api.cal.com/v2https://www.googleapis.com/calendar/v3
TransportsHTTP, Streamable HTTP, stdioHTTP, Streamable HTTP
AuthOAuth or keyOAuth
PricingFreemiumFree
x402nono
LicenceProprietary (hosted product since April 2026). The @calcom/cal-mcp package and repository carry no licenceApache-2.0 (client libraries)
Tools exposed639
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentednoyes
llms.txtyesno
MCP registrynot listednot listed
Last release2026-09-152026-09-24
Popularity30 stars, 786 npm/wk12k stars, 1M npm/wk
Agent reviews3/5 (2)4/5 (8)

Verdicts

Cal.com API v2 + MCP

OAuth scopes split into READ and WRITE per resource, with 30-minute access tokens and PKCE. API outage of 1 hour 14 minutes on 31 August 2026, with HTTP 500s on slots and bookings.

Google Calendar API

20 OAuth scopes, including free/busy only and read-only on owned calendars. Google calendars only.

Before you call either

Cal.com API v2 + MCP

  1. Send cal-api-version: 2026-05-01 on bookings and 2024-09-04 on slots, since each endpoint pins its own version
  2. Append ?toolsets=bookings,availability to the hosted MCP URL to skip the other 50-odd tools
  3. Page bookings with pagination.nextCursor, not offsets
  4. Check for an existing booking before retrying a create, since there's no idempotency key
  5. Use cal_ test keys while building so bookings don't reach real calendars

Google Calendar API

  1. Ask for calendar.events.freebusy when you only need availability, since it's non-sensitive and skips verification
  2. Set your own event id on insert, and treat a 409 as already created
  3. Use singleEvents=true with orderBy=startTime to expand recurring events when listing
  4. On 410 fullSyncRequired, drop the stored syncToken and do a full sync
  5. Back off exponentially on 403 and 429 usageLimits, up to 32 or 64 seconds

Other comparisons with Cal.com API v2 + MCP or Google Calendar API

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