When trying to use Repository Access Tokens (RAT), Project Access Tokens (PAT) or Workspace Access Tokens (WAT)  to POST/PUT/DELETE a deploy key (repository access key) through the API :

curl --request POST --url 'https://api.bitbucket.org/2.0/repositories/<workspace>/<repository>e/deploy-keys' --header 'Authorization: Bearer <Repository Access token>' -d 
'{ "label": "newlabel", "key": "ssh-rsa <rest of the key>"}'

The following error is returned :

{ "type": "error",  "error": {"message": "This API is not accessible by this authentication mechanism"}} 

This feature request is to implement the ability to use RATS, PATs, and WATs for POST/PUT/DELETE operations in the following endpoints : 

• https://developer.atlassian.com/cloud/bitbucket/rest/api-group-deployments/#api-repositories-workspace-repo-slug-deploy-keys-post
• https://developer.atlassian.com/cloud/bitbucket/rest/api-group-deployments/#api-repositories-workspace-repo-slug-deploy-keys-key-id-put
• https://developer.atlassian.com/cloud/bitbucket/rest/api-group-deployments/#api-repositories-workspace-repo-slug-deploy-keys-key-id-delete

It's currently only possible to use the username and app password or OAuth access token as the credentials for authentication.