contract/agreement_legal/views/agreement_type.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

    <!-- Agreement Type List View-->
    <record model="ir.ui.view" id="partner_agreement_type_list_view">
        <field name="name">Agreement Type List</field>
        <field name="model">agreement.type</field>
        <field name="inherit_id" ref="agreement.agreement_type_list_view"/>
        <field name="arch" type="xml">
            <field name="name" position="after">
                <field name="agreement_subtypes_ids" string="Sub-Types"/>
            </field>
       </field>
    </record>

    <!-- Agreement Type Form View -->
    <record model="ir.ui.view" id="partner_agreement_type_form_view">
        <field name="name">Agreement Type Form</field>
        <field name="model">agreement.type</field>
        <field name="inherit_id" ref="agreement.agreement_type_form_view"/>
        <field name="arch" type="xml">
            <xpath expr="//sheet" position="inside">
                <field name="agreement_subtypes_ids"
                       nolabel="1">
                    <tree editable="bottom">
                        <field name="name"/>
                    </tree>
                </field>
            </xpath>
        </field>
    </record>

    <!-- Actions opening views on models -->
    <record model="ir.actions.act_window" id="partner_agreement_action_type">
        <field name="name">Agreement Types</field>
        <field name="res_model">agreement.type</field>
        <field name="view_mode">tree,form</field>
    </record>

</odoo>