Surprisingly, Amazon Alexa doesn’t have a good way to search for Alexa skills by voice. You can’t say that you want to play word games, need a skill to check airport security wait times, or feel like meditating. Alexa doesn’t know what to tell you.

Amazon released its own “Skill Finder” skill last year, but it’s a bare-bones experience that can only read off the most popular apps in certain vague categories, or list the top or newest Alexa skills. You can’t ask it for a skill with a specific use case or functionality.

So the Allen Institute For Artificial Intelligence figured it’d build a full-fledged voice keyword search engine for Alexa skills. Funded by Microsoft co-founder Paul Allen, AI2 is one of the largest not-for-profit AI institutes in the world.

AI2’s Alexa “Skill Search” allows people to simply say what they want to do, and it finds them matching skills. So you could say “I want to buy flowers” or “I want to check my flight status” or any of the examples above, and it will read you the descriptions of other Alexa skills that can help until you find one you want to enable. You can hear how it works below:

But when AI2 submitted the Skill Search engine to the Alexa platform, Amazon rejected it, citing that “We don’t allow skills that recommend skills to customers at this time. We will contact you if this feature becomes available.” TechCrunch asked Amazon for clarification, and the company only responded that “we don’t have anything to share outside our policy page (4a)”, referring to a rule barring any skill that “Offers a separate skill store or recommends other skills.”

It would seem that having this kind of skill search engine would be advantageous to Amazon. It provides a discovery opportunity for skill developers looking to get more users, and highlighting the breadth of skills could make Alexa look more attractive compared to alternatives like Google Home that don’t have as well established of an ecosystem.

It all begs the question of whether Amazon is preparing a much more powerful skill search engine of its own. Banning competitors ahead of such a launch could ensure greater traction for Amazon’s version, which would give it more control over the Alexa developer landscape.

Some might consider this unfair, but it’s pretty standard procedure in tech, and since the policy was clearly spelled out before AI2 submitted its search engine, Amazon isn’t pulling the rug out from anyone. Other platforms like Facebook frequently bar developers from replicating their own functionality or cut off developers who become a competitive threat. For example, Facebook blocked social graph access to chat competitor Voxer, and Live video access to filter app Prisma.

Wherever there’s search and discovery, there are opportunities for sponsored search results and placement, which could give Amazon another revenue stream from Alexa. Now it’s up to Amazon to build what it won’t let other developers provide.