nodejs express- server's get method gets 3 arguments

Can you please help me understand the following code? It seems that here the get method receives 3 arguments instead of 2.. What does it do with the object that is given to it as the third argument?

app.get('/query', function(req, res) {
                console.error('we shouldn't be here');
                res.writeHead(500);
                res.end('we shouldn't be here' + req.url);
            },
            {
                id: 'my_id',
                name: 'query',
                usage: 'get query',
                example: 'get query',
                params: {},
                broadcast: true, 
                response: { representations : [ 'application/json' ] }
            }
        );

Thanks, Li

This doesn't appear to be correctly written. In Express, a request handler can take a third paramater which is a function (commonly called next() which will be called if the handler decides not to handle the request (thus passing the request down to the next handler you defined). In your example, however, the third parameter is on object rather than a function, and it's not actually being passed to your request handler..

It's possible that you're basing your code on an example that uses a very early, now obsolete, version of Express.