This will be a little post that might save developers a bunch of their time.
As many of you already know, me and 
Steemit API's work very well, but the documentation is quite scarce. One of the basic tasks we had to accomplish is getting, for instance, the feed coming from the "new" section of a particular tag ("gamedev" in our case).
Using steem-js we first tried with getState:
steem.api.getState('/created/gamedev', function(err, result) {
console.log(err, result);
});
First thing to notice: "created" stands for "new" category. This call goes fine, but there is no way of retrieving a certain amount of posts from here. We need something more specific.
Get Discussions By Created (straight from the docs) seems the correct one:
steem.api.getDiscussionsByCreated(query, function(err, result) {
console.log(err, result);
});
Cool! But, wait.. what "query" parameter stands for? We haven't managed to find a documentation about this parameter, but in the examples folders from the GitHub account we managed to find something (server.js):
steem.api.getDiscussionsByActive({
limit: 10,
start_author: 'thecastle',
start_permlink: 'this-week-in-level-design-1-22-2017'
}, function(err, result) {
console.log(err, result);
});
So now we know something about that "query" parameter. Last thing we need is a way to get feed from "gamedev" tag. We guessed that "tag" would have worked, so we tried it.. and indeed it worked.
So, the ultimate call is the following:
steem.api.getDiscussionsByCreated({
limit: 10,
start_author: 'thecastle',
start_permlink: 'this-week-in-level-design-1-22-2017',
tag: 'gamedev'
}, function(err, result) {
console.log(err, result);
});
Where:
You can use the same format for getDiscussionsByHot and getDiscussionsByTrending.