Requests are held by the query tag with the attribute type determining the type of the request

<?xml version="1.0" encoding="UTF-8"?>
<envelope>
    <header>
        <actor>test</actor>
        <user>test</user>
        <password>test</password>
        <version>0.1b</version>
        <timestamp>20210424170000</timestamp>
        <transaction>12345</transaction>
    </header>
    <query type="type" product="hotel">
        <!-- QUERY -->
    </query>
</envelope>

Responses are held by the tag response tag with the attribute type determining the type of the response:

<?xml version="1.0" encoding="UTF-8"?>
<envelope>
    <header>
        <version>0.1b</version>
        <timestamp>20210424170000</timestamp>
        <transaction>12345</transaction>
    </header>
    <response type="type">
        <!-- RESPONSE -->
    </query>
</envelope>

In case of error the type attribute will contain the word error

<?xml version="1.0" encoding="UTF-8"?>
<envelope>
    <header>
        <version>0.1b</version>
        <timestamp>20210424170000</timestamp>
        <transaction>12345</transaction>
    </header>
    <response type="error">
        <!-- ERROR MESSAGE -->
    </response>
</envelope>