The OpenAPI JSON https://dac-static.atlassian.com/cloud/trello/swagger.v3.json?_v=1.498.0 for the Tello OpenAPI has the following errors and warning and because of that, no client can be generated from it:
Errors:
-attribute paths.‘/members/{id}/notificationsChannelSettings/{channel}/{blockedKeys}’(put).operationId is repeated
-attribute paths.‘/members/{id}/notificationsChannelSettings/{channel}’(put).operationId is repeated
-paths.‘/cards/{idCard}/customFields’. Declared path parameter idCard needs to be defined as a path parameter in path or operation level
-attribute components.schemas.Notification.items is missing
Warnings:
-attribute paths.‘/members/{id}/notificationsChannelSettings/{channel}/{blockedKeys}’(put).operationId is repeated
-attribute paths.‘/members/{id}/notificationsChannelSettings/{channel}’(put).operationId is repeated
-paths.‘/cards/{idCard}/customFields’. Declared path parameter idCard needs to be defined as a path parameter in path or operation level
-attribute components.schemas.Notification.items is missing
There is a related Atlassian support ticket for this issue:
https://support.atlassian.com/requests/TRELLO-162374/
Additionally, I found, that for different endpoints like PUT /actions/{id}/text and multiple more, the response object for the 200 response is missing. Because of this, that OpenAPI JSON is useless for generating clients out of it.