'How to add a banner/label to redoc
Looking at the Redoc demo and they have used a "Webhook" label beside their title but I couldn't figure out how to implement it specifically for other labels. How would I be able to implement this to show a "Beta" label? 
Solution 1:[1]
I wasn't able to find a way to accomplish this. What I ended up doing is adding a label in the description which supports html.
Solution 2:[2]
Don't think Redoc provides the capability to put customized label beside operation title (summary).
The webhook marker shown in your screenshot represents the "New pet" is not a normal API operation but a webhook. Please read here for how does Redoc support webhooks.
If you want to know more about webhooks, you could read this post.
Webhooks provide a mechanism where by a server-side application can notify a client-side application when a new event (that the client-side application might be interested in) has occurred on the server.
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | mocha |
| Solution 2 | aleung |