Acuity Scheduling API vs YouCanBookMe API

Acuity Scheduling API 56

Each reference page carries an OpenAPI 3.1 fragment for its own operation, generated by the docs platform from hand-written pages. No single downloadable specification was found (15). llms.txt is published and every page has a Markdown copy, but the index lists only five of 36 reference pages (8). Pages explain client and admin booking modes and when availability is validated, without when-not-to-use guidance (10). Parameters are typed with required fields, but there are no enums and datetime is any string PHP's strtotime accepts (8). Request examples, an error table and per-endpoint error codes (12). The path is versioned as v1, with no changelog found (3). Total 56.

YouCanBookMe API 10

The reference lives on Stoplight at ycbm.stoplight.io, which usually renders an OpenAPI file, but our reader got only the workspace shell, and no spec file was found at the usual paths; the help centre article on support.youcanbook.me sat behind a Cloudflare challenge. Scored absent (0 of 25). No llms.txt on youcanbook.me, the help centre or the Stoplight host (0). Descriptions, typed inputs and required fields unread (0 of 20, 0 of 15). The one response we saw is a JSON envelope with code, errors, httpCode, message and status, and the help centre gives a worked webhook payload (4 of 15). A /v1 path and x-api-version: 1.18 and x-api-revision headers, with a product updates page dated by month and no API changelog (6 of 15). 0 + 0 + 0 + 0 + 4 + 6 = 10.

Acuity Scheduling API 58

Graded as a hosted API. Statuspage site at status.acuityscheduling.com with incident history, though one component stands for the whole product (20). In the 90 days to 8 October 2026 the feed shows a critical disruption of 2 hours 5 minutes on 19 July and one of 18 minutes on 12 August, both marked as possibly affecting all users and services, plus a four-day iOS app fault and three minor integration incidents. Read as one major outage (10). 10 requests a second and 20 concurrent connections per IP (15). The 429 body is documented, with no Retry-After, backoff advice or idempotency key for booking writes (3). No SLA found, and the Developer Terms disclaim uninterrupted service (0). The v1 API is generally available (10). Total 58.

YouCanBookMe API 15

Read with the hosted lines. The help page links a status page at www.youcanbookmestatus.com, but the host did not resolve from our reader with or without www on 3 November 2026, so it is scored as not established rather than as a finding about the vendor (0). No readable history (5). No rate limit with a number in the help centre articles, the pricing page or the API's own error response; the API reference could not be read (0). No 429 or retry guidance and no idempotency key found (0). No SLA, and the terms say the service is not guaranteed to be available 100 per cent of the time (0). The API reports version 1.18 in its headers and is sold on the Team plan, so generally available (10). 0 + 5 + 0 + 0 + 0 + 10 = 15.

Acuity Scheduling API 44

max caps list size and excludeForms trims intake forms from appointments. No field selection (10). Filters by date, calendar, type and client, but no cursor or offset is documented, so long lists need date windows (10). Errors carry a status, a named code and a message, and a 404 suggests the nearest path (16). No idempotency key or safe-retry guidance for POST /appointments (0). Booking needs five fields and picks a calendar when none is given. SDKs exist for Node.js and PHP, both last released in 2019 (8). Total 44.

YouCanBookMe API 13

Response sizing, field selection and pagination are in the unread reference (3 of 25, 0 of 20). The error envelope names a machine code and a message an agent can branch on (8 of 20). No idempotency key or safe-retry guidance found (0 of 20). No official SDK, and the required parameters are unread (2 of 15). 3 + 0 + 8 + 0 + 2 = 13.

Acuity Scheduling API 15

No changelog or release notes found. The docs' own page dates show the OAuth guide edited on 1 October 2026 and the webhooks guide on 25 June 2026, which we count as the latest dated change (10). No three dated entries in 90 days (0). A developer email address and a support form, with no public issue tracker for the API (5). The Node.js and PHP SDKs were last tagged in July 2019 (0). No current package to assess (0). Total 15.

YouCanBookMe API 28

Read as a closed service. The newest product update is dated September 2026 (registered SMS numbers), within 90 days but not 30, taking the month's first day (20 of 30). The previous entry is November 2025, so fewer than three in 90 days (0 of 20). A help centre, a community forum at forum.youcanbook.me and one-to-one support for paid users, with a product updates page that carries no API items (8 of 15). No official SDKs found (0). No package to assess (0). 20 + 0 + 8 + 0 + 0 = 28.

Acuity Scheduling API 55

Closed service under Squarespace's Developer Terms of 16 December 2025, with MIT SDKs (15). The privacy policy of 15 July 2026 names acuityscheduling.com and states no retention periods. The DPA of the same date promises deletion within 90 days of cancellation on written request (15). No deprecation policy, and the Developer Terms allow changes to developer tools without notice (0). Sub-processors are disclosed only on request by email, and data may move to any country where Squarespace or its sub-processors operate, the US in particular (4). Total 34.

YouCanBookMe API 61

Closed service with terms (18 March 2026) naming AI Software (Capacity) UK Ltd under English law, which bar data-mining and robot tools without consent and let the company end membership without notice for a breach (15 of 30). The privacy notice (16 March 2026) states retention periods (24 months for booking data by default, 7 years for support messages), AWS hosting in the United States, a DPA on request and no training of external AI models on booking data; the security page says no subprocessor list is published, and the two agree on AWS (22 of 30). No deprecation policy or dated notice, and clause 18.4 allows changes to the service without notice (3 of 20). Providers are named in the privacy notice (AWS, Stripe, Google Analytics, Mixpanel, Hotjar, HubSpot) with US hosting, but there is no list with locations per processor (12 of 20). 15 + 22 + 3 + 12 = 52.