You can assign each of your agents to different websites or pages. In that way they can chat only with visitors from websites or specific pages your agents are assigned to.
You can assign an agent to websites or pages by following the steps below:
1. Click on Agents from the left menu and then click on Edit icon of the agent.
2. Click on Pages and then turn off "Handle chats on all pages".
3. Click on Add Page button, select the condition and then enter your URL.
4. Repeat the step above if you need more conditions.
5. Click on Update.
6. You're done :)
For example, if you add a page with condition "Contains" and "URL" mywebsite.com, then the agent will be able to chat with all visitors who are browsing any of your website pages who contain "mywebsite.com" in their URL address.
Now your agents can chat only with visitors from websites and pages they're assigned to.