Communication between react and api

Everything ok? I created a react application that communicates with a rails api. It is a very simple application, but there is this communication between react and api.

My question is… Do I need to create a token of authentication so that third parties do not use my api? Or can I somehow tell my api that it only responds to requests that come from my site?

Thank you for your help!

thank you both that give me some answers.

I came from work now, and sit to study a little, and I found about CORS. That is exactly what I was looking for.

Here is a guide specific about a gem that make it in Rails. https://www.stackhawk.com/blog/rails-cors-guide/

----- edit

As requested... here is my solution.

1. I installed the gem "rack-cors".

2. In config/initializers I created the file cors.rb with the following code:

Rails.application.config.middleware.insert_before 0, Rack::Cors do
  allow do
    origins "localhost:3000" #1
    resource "*", #2
      headers: :any,
      methods: [:get] #3
  end
end

#1 -> origins: are the origins that u want to accept connect to the api, in dev environment for example, u should place "localhost:3000" or "127.0.0.1:3000". Very important here!! domain + port, or u will get error.

#2 -> resources: are the resources that the specified domain may access. In example is * for all resources, but u could set just "/orders" or "/users". and even explain for each resource which header or methods u will accept.

#3 -> method: are the http methods that will accept, as: get, post, put etc