How can I get a script's function environment without having it calling a function?

I am creating a plugin and I have access to a script's Source but I don't have any method to retrieve it's function environment. How can I get a script's function environment externally?(If I can't, is there something alternative?)

ROBLOX Script

--[[
!plugin

#include a
--]]

.lua

local function include(doc, args, line)
	if (#args == 1) then
		if (C.Documents[args[1]]) then
			local target = C.Documents[args[1]]; 
			--Just think of target as a script object
			--How can I get the script env?
		else
			out(doc, line, 3, "Document '"..args[1].."' does not exist in storage!")
		end
	else
		out(doc, line, 3, "Invalid number of arguments.");
	end
end