REMAP {
    if from.url.path ~ /foo/ && txn-count() > 10 {
        inbound.req.@Client-Txn-Count = "{txn-count()}";
    }
}

SEND_RESPONSE {
    if from.url.path ~ /foo/ && ssn-txn-count() > 5 {
        inbound.resp.@Server-Txn-Count = "{ssn-txn-count()}";
    }
}
