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HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <help>
    <module>* prop=info (in) *
  Get basic page information such as namespace, title, last touched date, ...

This module requires read rights
Parameters:
  inprop              - Which additional properties to get:
                         protection            - List the protection level of each page
                         talkid                - The page ID of the talk page for each non-talk page
                         watched               - List the watched status of each page
                         notificationtimestamp - The watchlist notification timestamp of each page
                         subjectid             - The page ID of the parent page for each talk page
                         url                   - Gives a full URL to the page, and also an edit URL
                         readable              - Whether the user can read this page
                         preload               - Gives the text returned by EditFormPreloadText
                         displaytitle          - Gives the way the page title is actually displayed
                        Values (separate with '|'): protection, talkid, watched, notificationtimestamp, subjectid, url, readable, preload, displaytitle
  intoken             - Request a token to perform a data-modifying action on a page
                        Values (separate with '|'): edit, delete, protect, move, block, unblock, email, import, watch, translationreview, groupreview,
                            aggregategroups
  incontinue          - When more results are available, use this to continue
Examples:
  api.php?action=query&prop=info&titles=Main%20Page
  api.php?action=query&prop=info&inprop=protection&titles=Main%20Page
Help page:
  https://www.mediawiki.org/wiki/API:Properties#info_.2F_in
</module>
  </help>
</api>