MediaWiki:Apihelp-main-description
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Status: All features shown on this page should be working, but the API is still in active development, and may change at any time. Subscribe to the mediawiki-api-announce mailing list for notice of updates.
Erroneous requests: When erroneous requests are sent to the API, an HTTP header will be sent with the key "MediaWiki-API-Error" and then both the value of the header and the error code sent back will be set to the same value. For more information see API: Errors and warnings.