If you have existing tokens for a user, make a call to the verify_credentials endpoint. If you get an error back, tokens aren't valid.
Twitter doesn't provide 'pings' for when users un-authorise your application. On 5 May 2011, at 12:01, ss.require wrote: > Let's consider I have got the access token and works with the API > successfully during some time. At some point the user restricts the > access for my App in the twitter's application tab or by some other > means. It would be a good idea to let my app to know about that so I > won't send useless requests. How my app shoud be notified if the > access token is revoked? Maybe during request I will get the special > error that indicates that or twitter will send me notification about > that? > > -- > Twitter developer documentation and resources: http://dev.twitter.com/doc > API updates via Twitter: http://twitter.com/twitterapi > Issues/Enhancements Tracker: http://code.google.com/p/twitter-api/issues/list > Change your membership to this group: > http://groups.google.com/group/twitter-development-talk -- Scott Wilcox @dordotky | sc...@dor.ky | http://dor.ky +44 (0) 7538 842418 | +1 (646) 827-0580 -- Twitter developer documentation and resources: http://dev.twitter.com/doc API updates via Twitter: http://twitter.com/twitterapi Issues/Enhancements Tracker: http://code.google.com/p/twitter-api/issues/list Change your membership to this group: http://groups.google.com/group/twitter-development-talk