API:Siteinfo

Siteinfo returns overall site information. The code for the siteinfo function is located at.

General
The general option can return the following results:

Interwiki
The attributes provided in each  element include:

Namespaces
Each namespace is given within its own element, which contains several attributes:

Rightsinfo
In the best case this will provide:

If $wgRightsPage is set,  is the URL to a page whose meaning has to be interpreted separately and is not output by the API. The API doesn't output whatever MediaWiki:Copyright contains.

Statistics
This section provides similar info to Special:Statistics, along with the number of jobs in the job queue, in the following elements:

Other statistics may be included via the APIQuerySiteInfoStatisticsInfo hook.

Usergroups
This retrieves a list of all groups on the wiki, along with their rights and possibly other statistics.