Bitbucket Cloud REST API

In Bitbucket Cloud, open your account settings and go to OAuth / OAuth consumers in Bitbucket Cloud settings, then register an OAuth consumer and copy its client ID and secret. Atlassian's Bitbucket OAuth docs are at Use OAuth on Bitbucket Cloud and the REST auth overview is at Authentication methods.

Create an app password from Create an app password / Using app passwords. Choose the needed permissions, save, and copy the generated app password. Use it together with your Bitbucket username for HTTP Basic auth.

Create a token from the repository's Access tokens settings as described in Create a repository access token and Repository access tokens. Choose the required repository scopes and copy the token when shown.

Create a token from the project's Access tokens settings as described in Create a project access token and Project access tokens. Choose the required project scopes and copy the token when shown.

Create a token from the workspace's Access tokens settings as described in Create a workspace access token and Workspace access tokens. Choose the required workspace scopes and copy the token when shown.

This JWT is issued for a Bitbucket Cloud Connect app installation and is used for the addon endpoints. The addon docs state these endpoints only support JWT auth and identify the installation that way; obtain it through the Bitbucket Cloud Connect app installation flow described in Addon and Bitbucket Connect/Forge migration docs linked from Atlassian developer docs.