This proimse type assures that a value string, containing the matching substring, will be present in the specified node within the XML file. If the substring is not found, the default promise is to append the substring to the end of the existing value string, within the specified node. The specified node is determined by body-attributes. The promise object referred to is a literal string of text.

bundle edit_xml example

  "text content to be appended to existing text, including whitespace, within specified node"
    select_xpath => "/Server/Service/Engine/Host/Alias";

Note that typically only a single value string, within a single specified node, is inserted in each insert_text promise. You may of course have multiple promises that each insert a value string.