Listening to a specific extension - Extenspy?

I need a feature that allows listening in to a specific extension. ChanSpy is insufficient, as it merely spies on the channel, and is cumbersome to use.
So I saw the ExtenSpy asterisk command, but I have absolutely no idea how to use it. How would I go about implementing a new feature in my FreePBX, to let me spy specific extensions?
Like, say, dialing *111[extension]. E.g. *111202 listens to whatever is going on at the 202 extension.
I saw no modules that do this. How can I do this?

Thanks in advance.

There’s an ongoing discussion on that topic over here :

And an article here:

See if those are of any use to you…

This is not exactly the same, but iSymphony manager has a “barge in” feature - you can listen to any ongoing phone call. Just click an icon in the manager, your extension will ring, and you can listen to the conversation.

place the below code in your extension_custom.conf

exten => _*111x.#,1,Macro(user-callerid,)
exten => _*111x.#,n,Answer
exten => _*111x.#,n,NoCDR
exten => _*111x.#,n,Wait(1)
exten => _*111x.#,n,ChanSpy(sip/${EXTEN:4},q)
exten => _*111x.#,n,Hangup

Can this be applied successfully to Distro? When I do what you say, *97 404’s

Is there anything at all that can be added to make extenspy work?

Check your “feature codes” page look for “Chanspy 555”