list-credential.groovy

/**
Author: kuisathaverat
Description: List ID and Description of all credentials on a Jenkins Instance.
**/
import com.cloudbees.plugins.credentials.Credentials

Set<Credentials> allCredentials = new HashSet<Credentials>();

def creds = com.cloudbees.plugins.credentials.CredentialsProvider.lookupCredentials(
      com.cloudbees.plugins.credentials.Credentials.class
);

allCredentials.addAll(creds)

Jenkins.instance.getAllItems(com.cloudbees.hudson.plugins.folder.Folder.class).each{ f ->
 creds = com.cloudbees.plugins.credentials.CredentialsProvider.lookupCredentials(
      com.cloudbees.plugins.credentials.Credentials.class, f)
  allCredentials.addAll(creds)
  
}

for (c in allCredentials) {
   println(c.id + ": " + c.description)
}