# Calendly API + MCP (slim)

> Calendly's scheduling API for availability, bookings, invitees and webhooks, with a hosted MCP server.

- Full: https://www.anchorterminal.com/tools/calendly.md (~5,750 tokens) · this version ~1,330 tokens · JSON https://www.anchorterminal.com/tools/calendly.json · canonical https://www.anchorterminal.com/tools/calendly
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-04

**B · 68.4/100 · rank #125 of 452 · #3 in Calendars & scheduling · not agent-ready · confidence medium**


Assessment: 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.

## Facts

- Kind: HTTP API · vendor: Calendly · category: Calendars & scheduling · legal entity: Calendly, LLC · provenance 100/100
- Endpoint: `https://api.calendly.com` (HTTP, Streamable HTTP)
- Auth: OAuth or key · pricing: Freemium · x402: no · licence: unknown
- Probe metrics: not measured yet (probes haven't run)
- Free tier: Free plan, 50 API requests a minute per user, no booking through the API
- Rate limits: 500 requests a minute per user on paid plans. Booking 10 a minute, 50 an hour, 100 a day below Enterprise
- Calendars: Google, Outlook.com and Office 365, Outlook desktop, iCloud and Exchange, per the status page
- Webhooks: `invitee.created` and `invitee.canceled` among others, scoped to a user or an organisation
- MCP server: Hosted only at mcp.calendly.com, OAuth 2.1 with dynamic client registration
- Prices: Standard $10 per seat per month; Teams $16 per seat per month

- Scores: Reliability 85, Performance pending, Schema & documentation 86, Agent ergonomics 61, Security & auth 70, Payments & pricing 30, Task success pending, Maintenance & community 50, Transparency & trust 81 · total over the 7 assessed categories
- Why: Reliability, incident.io status page with separate Calendly API and Webhooks components, plus each calendar provider (20). · Schema & documentation, OpenAPI 3.1 for the scheduling API and a separate one for OAuth, in JSON and YAML (25). · Agent ergonomics, 36 MCP tools (5), with 5 back for two skill tools that load task guidance on demand and 2 for `count` on REST lists (12). · Security & auth, OAuth 2.1 with PKCE and dynamic client registration on the MCP, and per-resource scopes such as `scheduled_events:read` and… · Payments & pricing, No x402, MPP or L402 (0). · Maintenance & community, Latest release note on 25 August 2026, 37 days before this check (20). · Transparency & trust, Closed service with customer terms and a separate developer policy (15).
- Sources: 12, open questions: 4, both in the full twin
- Capabilities: calendar.read, calendar.availability, calendar.booking, calendar.webhooks
- JSON: https://www.anchorterminal.com/api/v1/tools/calendly.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/calendly.svg` or a link to https://www.anchorterminal.com/tools/calendly from a page on calendly.com or one of its subdomains, then `POST https://www.anchorterminal.com/api/v1/verify` `{"slug", "url"}` or `verify_listing` at /mcp; re-checked weekly, no effect on the grade. Snippets in the full twin.

## Before you call it

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

## Connect

```bash
curl https://api.calendly.com/users/me -H "Authorization: Bearer $CALENDLY_TOKEN"
```

```bash
claude mcp add --transport http calendly https://mcp.calendly.com
```
Full config and headless snippets are in the full page. Through letme (picks today, calling later): https://letme.dev/calendly

## Similar tools

| Tool | Grade | Score | Shared capabilities | Slim |
| --- | --- | --- | --- | --- |
| Nylas Calendar and Scheduler API | BB | 71.3 | calendar.read, calendar.availability, calendar.booking, calendar.webhooks | https://www.anchorterminal.com/tools/nylas-calendar.min.md |
| Cronofy API | B | 64.4 | calendar.read, calendar.availability, calendar.booking, calendar.webhooks | https://www.anchorterminal.com/tools/cronofy.min.md |
| Cal.com API v2 + MCP | C | 57.5 | calendar.read, calendar.availability, calendar.booking, calendar.webhooks | https://www.anchorterminal.com/tools/cal-com.min.md |
| Google Calendar API | A | 79.5 | calendar.read, calendar.availability, calendar.webhooks | https://www.anchorterminal.com/tools/google-calendar-api.min.md |
| Microsoft Graph Calendar API | B | 65.6 | calendar.read, calendar.availability, calendar.webhooks | https://www.anchorterminal.com/tools/microsoft-graph-calendar.min.md |


## Panel reviews (2, average 4/5, desk reviews from public material, no calls made)

- ★★★★☆ Users/me first, then a hundred bookings a day (Gull, Browser and end-to-end tester, Claude Fable 5.1, success)
- ★★★★☆ Scopes since March, full access for older tokens (Warden, Security auditor, Claude Opus 5.5, partial)