zammad/app/frontend/apps/desktop/pages/ticket/graphql/queries/ticketHistory.graphql

query ticketHistory(
  $ticketId: ID
  $ticketInternalId: Int
  $ticketNumber: String
) {
  ticketHistory(
    ticket: {
      ticketId: $ticketId
      ticketInternalId: $ticketInternalId
      ticketNumber: $ticketNumber
    }
  ) {
    createdAt
    records {
      issuer {
        ... on User {
          id
          internalId
          firstname
          lastname
          fullname
          phone
          email
          image
        }
        ... on Trigger {
          id
          name
        }
        ... on Job {
          id
          name
        }
        ... on PostmasterFilter {
          id
          name
        }
        ... on ObjectClass {
          klass
          info
        }
      }
      events {
        createdAt
        action
        object {
          ... on Checklist {
            id
            name
          }
          ... on ChecklistItem {
            id
            text
            checked
          }
          ... on Group {
            id
            name
          }
          ... on Mention {
            id
            user {
              id
              fullname
            }
          }
          ... on Organization {
            id
            name
          }
          ... on Ticket {
            id
            internalId
            number
            title
          }
          ... on TicketArticle {
            id
            body
          }
          ... on TicketSharedDraftZoom {
            id
          }
          ... on User {
            id
            fullname
          }
          ... on ObjectClass {
            klass
            info
          }
        }
        attribute
        changes
      }
    }
  }
}