My visit to Signs was one of the most interesting parts of my trip to Toronto. I was a little nervous when my friend suggested going here as I had no idea what to expect but I'm so glad that I did.
As others have mentioned, all of the servers here are deaf. This means all ordering and conversation with staff is done using sign language. To start your meal, the host joins your server and the table to introduce them and teach you some basic signs to get things started (yes, no, thank you, etc.). They also let you know that unlike most other restaurants, it isn't rude to put up your hand here if you need something.
In addition to the initial introduction, there are also helpful conversational guides on every table and all of the menu items are accompanied by instructions for how to sign them. All of the servers are equipped with tablets so when you try signing your order, they can confirm with you that they understood by showing you a picture of it. It was a very humbling experience being put in the position where you're struggling to communicate in the dominant form. That in itself was worth the visit.
Aside from the unique dining experience offered at Signs, the food is actually really good! As a vegetarian I was blown away by the number of creative choices that were clearly marked on the menu. There is a great selection of vegan and gluten-free dishes as well. The butternut squash ravioli was delicious and I also really enjoyed my lychee martini. This seems like it would be a cool place to come back for a drink at the bar.