curl --request POST \
  --url https://api.openworklabs.com/v1/connectors/github/validate-target \
  --header 'Content-Type: application/json' \
  --data '
{
  "installationId": 123,
  "repositoryId": 123,
  "repositoryFullName": "<string>",
  "branch": "<string>",
  "ref": "<string>"
}
'

{
  "ok": true,
  "item": {
    "branchExists": true,
    "defaultBranch": "<string>",
    "repositoryAccessible": true
  }
}