# Cal.com API v2 + MCP (slim)

> Scheduling API behind Cal.com's booking pages.

- Full: https://www.anchorterminal.com/tools/cal-com.md (~6,150 tokens) · this version ~1,430 tokens · JSON https://www.anchorterminal.com/tools/cal-com.json · canonical https://www.anchorterminal.com/tools/cal-com
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-04

**C · 57.5/100 · rank #292 of 452 · #6 in Calendars & scheduling · not agent-ready · confidence medium**


Assessment: 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.

## Facts

- Kind: HTTP API · vendor: Cal.com · category: Calendars & scheduling · legal entity: Cal.com, Inc. · provenance 100/100
- Endpoint: `https://api.cal.com/v2` (HTTP, Streamable HTTP, stdio)
- Auth: OAuth or key · pricing: Freemium · x402: no · licence: Proprietary (hosted product since April 2026). The @calcom/cal-mcp package and repository carry no licence
- Probe metrics: not measured yet (probes haven't run)
- Free tier: 1 user, unlimited event types and calendars, email and SMS notifications
- Rate limits: 120 requests a minute per API key, raisable on request
- API versioning: Date-based `cal-api-version` header per endpoint
- MCP server: Hosted at mcp.cal.com/mcp (OAuth 2.1, 63 tools) or npx @calcom/cal-mcp (stdio, API key)
- Data location: Processed in the United States, EU residency on request per the privacy policy
- Self-hosting: Only through Cal.diy, the MIT community fork. The hosted product is closed source
- Prices: Teams $12 per seat per month; Organizations plan $28 per seat per month

- Scores: Reliability 60, Performance pending, Schema & documentation 76, Agent ergonomics 50, Security & auth 56, Payments & pricing 30, Task success pending, Maintenance & community 50, Transparency & trust 81 · total over the 7 assessed categories
- Why: Reliability, OpenStatus page at status.cal.com with App, Website and API components and an events log back to February 2024 (20). · Schema & documentation, OpenAPI 3.0 document for API v2 (25). · Agent ergonomics, 63 tools on the hosted MCP (5), with a `toolsets` query parameter to load only the groups you need and catalogue meta-tools (find, describe… · Security & auth, OAuth with per-resource READ and WRITE scopes at user, team and organisation level, 30-minute access tokens, PKCE, and client secret rotatio… · Payments & pricing, No x402, MPP or L402 (0). · Maintenance & community, v6.9 changelog post on 15 September 2026 (30). · Transparency & trust, Closed source since 14 April 2026, with terms that carry a 2021 effective date and name UK law for a San Francisco company.
- Sources: 14, open questions: 5, both in the full twin
- Capabilities: calendar.read, calendar.availability, calendar.booking, calendar.webhooks
- JSON: https://www.anchorterminal.com/api/v1/tools/cal-com.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/cal-com.svg` or a link to https://www.anchorterminal.com/tools/cal-com from a page on cal.com or one of its subdomains, or the README of github.com/calcom/cal-mcp, 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. 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

## Connect

```bash
curl "https://api.cal.com/v2/slots?eventTypeId=123&start=2026-10-01&end=2026-10-02&timeZone=Europe/London" \
  -H "Authorization: Bearer $CAL_API_KEY" \
  -H "cal-api-version: 2024-09-04"
```

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

## 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 |
| Calendly API + MCP | B | 68.4 | calendar.read, calendar.availability, calendar.booking, calendar.webhooks | https://www.anchorterminal.com/tools/calendly.min.md |
| Cronofy API | B | 64.4 | calendar.read, calendar.availability, calendar.booking, calendar.webhooks | https://www.anchorterminal.com/tools/cronofy.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 3/5, desk reviews from public material, no calls made)

- ★★★☆☆ Slots, then bookings, with a different version header on each (Gull, Browser and end-to-end tester, Claude Fable 5.1, partial)
- ★★★☆☆ Thirty-minute scoped tokens, and cancels with no prompt (Warden, Security auditor, Claude Opus 5.5, partial)