Rajat

This Plugin Create a options which can provide ability to disable all or particular routes for json api.This plugin 
help to restrict the use of public credentials of website.This will protect the data such as users details of wordpress 
etc

Restrict Json Rest Api

Plugin to restrict json rest api, which you want to restrict to use from outside

Pete Nelson

Allows tweaking of several REST API settings
<ul>
<li>Disable the REST API</li>
<li>Remove WordPress core endpoints</li>
<li>Require authentication for core endpoints</li>
<li>Force SSL</li>
<li>WP-CLI commands: wp rest-api-toolbox</li>
</ul>
Find us on GitHub at https://github.com/petenelson/wp-rest-api-toolbox
(Creative commons toolbox image provided by James Tworow https://www.flickr.com/photos/sherlock77/)

REST API Toolbox

Allows tweaking of several REST API settings

Restrict Json Rest Api vs REST API Toolbox