Full menu of options available in system.xml

system.xml

<config>
  <system>
    <!--You have a CHOICE of the next 2 items at this level-->
    <tab id="string" translate="string" sortOrder="1.5E2" class="string">
      <label>string</label>
    </tab>
    <section id="string" translate="string" type="string" sortOrder="1.5E2" showInDefault="3" showInStore="3" showInWebsite="3" canRestore="3" advanced="false" extends="string">
      <!--You have a CHOICE of the next 7 items at this level-->
      <label>string</label>
      <class>string</class>
      <tab>string</tab>
      <header_css>string</header_css>
      <resource>stringstring</resource>
      <group id="string" translate="string" type="string" sortOrder="1.5E2" showInDefault="3" showInStore="3" showInWebsite="3" canRestore="3" advanced="true" extends="string">
        <!--You have a CHOICE of the next 14 items at this level-->
        <label>string</label>
        <fieldset_css>string</fieldset_css>
        <frontend_model>string</frontend_model>
        <clone_model>string</clone_model>
        <clone_fields>3</clone_fields>
        <help_url type="string" scope_info="string">http://www.your.org/aeoliam/quae</help_url>
        <more_url type="string" scope_info="string">http://www.corp.org/temperat/per</more_url>
        <demo_link type="string" scope_info="string">http://www.test.com/regemque/nimborum</demo_link>
        <comment>string</comment>
        <hide_in_single_store_mode>3</hide_in_single_store_mode>
        <field id="string" translate="string" type="string" sortOrder="1.5E2" showInDefault="3" showInStore="3" showInWebsite="3" canRestore="3" advanced="false" extends="string">
          <!--You have a CHOICE of the next 24 items at this level-->
          <label>string</label>
          <comment model="string">
            foedere
            <!--You may enter ANY elements at this point-->
            <AnyElement/>
            ferant
          </comment>
          <tooltip>string</tooltip>
          <hint>string</hint>
          <frontend_class>string</frontend_class>
          <frontend_model>string</frontend_model>
          <backend_model>string</backend_model>
          <source_model>string</source_model>
          <config_path>string</config_path>
          <validate>string</validate>
          <can_be_empty>3</can_be_empty>
          <if_module_enabled>string</if_module_enabled>
          <base_url type="string" scope_info="string">http://www.corp.org/et/turbine</base_url>
          <button_url type="string" scope_info="string">http://www.any.org/speluncis/profundum</button_url>
          <more_url type="string" scope_info="string">http://www.my.com/flammas/ac</more_url>
          <demo_url type="string" scope_info="string">http://www.my.com/ac/caelumque</demo_url>
          <button_label>string</button_label>
          <hide_in_single_store_mode>3</hide_in_single_store_mode>
          <upload_dir config="string" scope_info="string">string</upload_dir>
          <source_service idField="string" labelField="string" includeEmptyValueOption="true">string</source_service>
          <options>
            <!--1 or more repetitions:-->
            <option label="string">string</option>
          </options>
          <depends>
            <!--Zero or more repetitions:-->
            <field id="string" separator="string" negative="3">string</field>
          </depends>
          <attribute type="string">
            circum
            <!--You may enter ANY elements at this point-->
            <AnyElement/>
            aris
          </attribute>
          <requires>
            <!--You have a CHOICE of the next 2 items at this level-->
            <field id="string">string</field>
            <group id="string"/>
          </requires>
        </field>
        <!--Zero or more repetitions:-->
        <group/>
        <depends>
          <!--Zero or more repetitions:-->
          <field id="string" separator="string" negative="3">string</field>
        </depends>
        <attribute type="string">
          coniunx
          <!--You may enter ANY elements at this point-->
          <AnyElement/>
          praeterea
        </attribute>
      </group>
      <frontend_model>string</frontend_model>
    </section>
  </system>
</config>