This lightweight module creates an opensearch autodiscovery link on every page of your site, as described here. It can serve the description document from a static file, but if no such file exists, it will create a dynamic one with some potentially reasonable defaults.
By default, the description document is located at
/opensearch.xml, and is generated dynamically. To use a static file, copy or rename the
opensearch_link/example.xml file to
opensearch_link/opensearch.xml and edit it to suit your site. The module looks for that file and uses it automatically if it exists.