Shawn

This plugin integrates JWT authentication and automates user creation. The plugin is written for AAF Rapid Connect, but can be used for other providers too.
Here is how this plugin works:
<ol>
<li>Generate a secrete key with command: tr -dc ‘[[:alnum:][:punct:]]’ < /dev/urandom | head -c32 ;echo</li>
<li>Register the key and call back URL http://yoursite.com/wp-json/jwt-auth/v1/callback with your authentication provider.</li>
<li>Specify authentication and user creation parameters. Those marked with * are required.</li>
</ol>

JWT Authenticator

This plugin integrates JWT authentication and automates user creation.

hauxh

This plugin allows you to require a secret key that is passed via the URL: http://example.com/post-title/?key=[string] 
Specify the key in a custom value called “key” with the [string] or use the built in widget.
Stable version of the plugin are pushed to the WordPress repository, 
but the latest version of the plugin can be found at: 
https://bitbucket.org/excion/wpkeyme/
Issues/Bugs: https://bitbucket.org/excion/wpkeyme/issues

WPKeyMe

This plugin allows you to require a secret key that is passed via the URL: http://example.com/post-title/?key=[string]

JWT Authenticator vs WPKeyMe