~/CLIRank

Best Calendar & Scheduling APIs for AI Agents in 2026

Browse the top Calendar & Scheduling APIs used by developers worldwide. Below: the top 7 Calendar & Scheduling APIs by CLIRank score, the independent rubric for how well an API actually works with AI coding agents like Claude Code and Cursor.

1
Calendly/10Scheduling

Scheduling automation API for booking meetings with availability rules.

Best for: De facto standard for scheduling - everyone knows it

manage event typeslist scheduled eventscheck availabilitymanage invitees
2
Cal.com/10Scheduling

Open-source scheduling platform with API for booking and availability management.

Best for: Open source Calendly alternative - self-host for free

manage bookingsset availabilitycreate event typesmanage users
3
Nylas/10Calendar Integration

Universal API for calendar, email, and contacts across providers.

Best for: Universal calendar and email API - one integration for Google, Microsoft, Exchange

sync calendarsmanage eventscheck availabilitysync emails
npm install nylas
4
Cronofy/10Calendar Integration

Unified calendar API with scheduling, availability, and calendar sync.

Best for: Enterprise-grade calendar integration with good compliance

sync calendarsmanage eventscheck availabilityschedule meetings
npm install cronofy-node
5
Doodle/10Scheduling

Group scheduling API for finding common availability across participants.

Best for: Best for group scheduling polls - find a time that works for everyone

create pollsfind availabilityschedule group meetingssend invitations
6
Acuity Scheduling/10Scheduling

Appointment scheduling API with calendar sync and payment collection.

Best for: Best for service businesses - intake forms, payments, packages

manage appointmentscheck availabilitycollect paymentssend reminders
7
SavvyCal/10Scheduling

Scheduling tool with prioritised availability and overlay calendars.

Best for: Best UX for scheduling - prioritises recipients over senders

manage scheduling linksset availabilityprioritise time slotsmanage events

Frequently asked questions

What makes an Calendar & Scheduling API "agent-friendly"?

For AI coding agents, the highest-impact signals are: an official SDK on npm or PyPI, environment variable authentication (no browser OAuth flow), JSON responses that parse cleanly, machine-readable pricing, and reasonable rate limits for scripted use. APIs missing more than two of these are painful for agents to use reliably.

How do you score Calendar & Scheduling APIs?

Each API is rated on 8 signals worth 1-2 points each (11 raw, normalised to 10). The full rubric: official SDK (+2), env var auth (+2), headless compatible (+2), CLI tool (+1), JSON response (+1), curl/CLI docs examples (+1), reasonable rate limits (+1), machine-readable pricing (+1). The top-scoring API in this category right now is Calendly at null/10.

Why isn't [my favourite API] on this list?

This list shows the top 7 Calendar & Scheduling APIs by score. The full ranking includes 7 APIs in this category. If yours is missing entirely, submit it at clirank.dev/submit - it gets auto-scored and added if it clears the threshold.

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