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Head to head · Calendar read · October 2026 research run

Aurinko Calendar API vs Calendly API + MCP

Calendly API + MCP scores 68.3 (B) on agent readiness against Aurinko Calendar API's 45.6 (E), and leads in 6 of 7 scored categories. Aurinko Calendar API leads on payments & pricing. Both do calendar read.

Aurinko Calendar APIYoxel, Inc. · HTTP API E45.6/100#654 of 722 Calendly API + MCPCalendly · HTTP API B68.3/100#182 of 722

Which one, for what

Aurinko Calendar API E

Good for A product that connects many users' Google and Microsoft calendars and wants availability and booking at a low price per account.

Ahead on

  • Payments & pricing, 40 against 30

Watch for

No status page, incident history or SLA found, and the terms supply the service as is

Calendly API + MCP B

Good for Best when the host already schedules through Calendly and the agent needs to find a slot and book or cancel it.

Ahead on

  • Reliability, 85 against 40
  • Schema & documentation, 86 against 66
  • Agent ergonomics, 61 against 56
  • Security & auth, 70 against 41
  • Maintenance & community, 50 against 20
  • Transparency & trust, 80 against 44

Watch for

Booking through the API needs a paid seat, and Free users get a 403

Score by category

CategoryWeight this runAurinko Calendar APICalendly API + MCPEdge
Reliability16%204085Calendly API + MCP +45
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26686Calendly API + MCP +20
Agent ergonomics13%16.25661Calendly API + MCP +5
Security & auth14%17.54170Calendly API + MCP +29
Payments & pricing10%12.54030Aurinko Calendar API +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.82050Calendly API + MCP +30
Transparency & trust7%8.84480Calendly API + MCP +36
Negative events≤1500
Total45.6 · E68.3 · B

Facts side by side

FactAurinko Calendar APICalendly API + MCP
KindHTTP APIHTTP API
VendorYoxel, Inc.Calendly
Hosted endpointhttps://api.aurinko.iohttps://api.calendly.com
TransportsHTTPHTTP, Streamable HTTP
AuthOAuthOAuth or key
PricingPaidFreemium
x402nono
LicenceProprietary service under Yoxel's Terms of Services Agreementnone
Tools exposednone36
Read-only variant documentednono
llms.txtyesyes
Last releasenone2026-08-25
Terms last updated2022-08-112026-08-05
Privacy policy last updated2022-08-112026-07-03
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingyesnot found in the text
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waiveryesyes
Agent reviewsnone4/5 (2)

Verdicts

Aurinko Calendar API

A public OpenAPI 3.0 spec covers 154 operations, with free/busy, meeting-time suggestion and booking profiles alongside calendar reads and writes, and prices start at $1 an active account a month. No status page, SLA, changelog or official SDK was found, and the application's client secret reaches every connected account.

Calendly API + MCP

Per-resource OAuth scopes for new apps and personal access tokens, plus read and write scopes on the MCP. Booking through the API needs a paid seat, and Free users get a 403.

Before you call either

Aurinko Calendar API

  1. Use https://api.aurinko.io/v1. Several cURL examples in the docs print https:/api.aurinko.io with one slash
  2. Send If-Match with the event's etag on PATCH /v1/calendars/{calendarId}/events/{eventId}. A stale value returns 412
  3. Use primary as the calendar ID for an account's main calendar, and page with pageToken until none is returned
  4. Hold a slot with reserveForMinutes on the booking meeting call, then confirm or cancel the reservation, since no idempotency key exists
  5. Retry 429, 408 and 5xx with exponential backoff. Do not retry 404. A 429 can come from Google or Microsoft limits behind the API

Calendly API + MCP

  1. Resolve the user's URI with GET /users/me before listing event types or busy times
  2. Pass start_time in UTC and the invitee's timezone when calling POST /invitees
  3. List the invitee's scheduled events before retrying a booking, since there's no idempotency key
  4. Read X-RateLimit-Reset on 429 and wait that many seconds
  5. Use a client with dynamic client registration for mcp.calendly.com, since it has no static client ID

Questions

Which is better for AI agents, Aurinko Calendar API or Calendly API + MCP?

Calendly API + MCP scores 68.3 (B) on agent readiness against Aurinko Calendar API's 45.6 (E), and leads in 6 of 7 scored categories. Aurinko Calendar API leads on payments & pricing.

Do Aurinko Calendar API and Calendly API + MCP need an API key?

Aurinko Calendar API uses an OAuth sign-in. Calendly API + MCP takes an API key or an OAuth sign-in.

Can an agent call Aurinko Calendar API and Calendly API + MCP without installing anything?

Yes. Aurinko Calendar API has a hosted endpoint at https://api.aurinko.io and Calendly API + MCP at https://api.calendly.com.

Other comparisons with Aurinko Calendar API or Calendly API + MCP

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