librex/opensearch.xml

<?xml version="1.0" encoding="utf-8"?>
<OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">
  <ShortName>LibreX</ShortName>
  <Description>A meta search engine for Google.</Description>
  <InputEncoding>UTF-8</InputEncoding>
  <LongName>LibreX search</LongName>
    <Url rel="results" type="text/html" method="post" template="http://localhost/search.php">
        <Param name="q" value="{searchTerms}" />
    </Url>

  <Url type="application/opensearchdescription+xml"
      rel="self"
      template="/opensearch.xml?method=POST" />
</OpenSearchDescription>