ASPEN, Colorado — “I think of Twitter primarily as a news system,” Twitter cofounder and board member Ev Williams said today.

That, in the long run, has shaped the way the service grew. Six years ago, Williams said, the company made the decision to see its primary product not primarily as a social network but as a real-time information-sharing network.

Williams was speaking onstage today at Fortune’s Brainstorm Tech conference.

The result, he said, is that Twitter contains everything you might want to know about — like today’s news of a nuclear deal with Iran — but it’s not necessarily very easy to find it.

Consequently, Twitter is busy building new tools to better organize information so you can actually find it.

But when asked about the role of third-party developers in that job, Williams was a little cagey.

“There’s a storyline about Twitter that these third-party developers and apps drove all this growth, and I don’t think that’s exactly true,” Williams said.

However, he acknowledged that the company has not developed its platform to the extent that it could. Moves like cutting off the ability for third-party developers to create their own Twitter clients didn’t exactly help.

The unfettered, open API “wasn’t a win-win for the users, developers, and the company,” Williams said, by way of explanation.

Unstated by Williams: It was actually more of a loss for the third part of that trio — Twitter itself — which was losing control of its key asset, the “firehose” of tweets and associated data about them.

Now, however, there’s a sign that Williams might recognize the need for more openness.

“Twitter should be more of a platform than it is,” Williams said.

However, he didn’t offer specifics on how it might achieve that goal.

That’s probably a project best left to the next chief executive.