API registry / Picqer
Picqer
No machine-readable spec. Picqer API docs: https://picqer.com/en/api (HTML docs only; official PHP client at https://github.com/picqer/picqer-php. Per-tenant base URL https://{subdomain}.picqer.com/api/v1/.)
Picqer publishes no machine-readable API spec.