As stated in the README.md, this addon can be installed by placing it in the server's addons folder, however this will not work if there is no addon.json file.

As suggested by code_gs

You could do the the actual position testing inside of a coroutine so that the server doesn't have to halt to find the player a clear position.

The "unstuck_debug" convar should save across sessions, be accessible through Player:GetInfoNum(), and have a description provided through the 5th argument.

If possible the help text should be defined in a variable, as this will allow the future expansion of your addon through the addition of a locale library, allowing the translation of the help text and the chat commands (as described in #2 ).

Having the userdata argument (argument 4) set to true will allow the value of this convar to be networked to the server, allowing the server to discriminate amongst players to whom it should send the debug information, as opposed to having it sent to all players. By doing this, and moving the CreateClientConVar call to the server, you can then monitor who is using the debug feature. This may in the future allow moderation to prevent its exploitation.

In time, this should be replaced, so as to prevent players not needing the debug information to access it, with a concommand that acts like a convar.

This may be replaced with good use of the table.HasValue( table tbl, any value ) function. While not effecient for large tables, it will increase the readability of the code by replacing such an if station with a dictionary search. This would also allow server owners to customize the dictionary to their own language.

Consider the following:

Unstuck.Configuration = {
	Command = {
		Prefix = { "!", "/" },
		String = { "stuck", "unstuck"}
	}
}

The following can then be achieved:

hook.Add("PlayerSay", "Unstuck.PlayerSay", function( ply, text )
	
	text = string.lower( text )

	// Check for the command prefix, terminate call if not present
	if ( not table.HasValue( 
		Unstuck.Configuration.Command.Prefix,
		text:sub(1, 1)
	 ) ) then return end
	
	// check for the command string, terminate call if not present
	if ( not table.HasValue( 
		Unstuck.Configuration.Command.String, 
		text:sub( 2, #text ) 
	) ) then return end

	//if ( text == "!unstuck" or text == "!stuck" or text == "/stuck" or text == "/unstuck" ) then

	/* ... */

Whenever a message is sent using this function, the first 3 arguments are always identical, and the 4th argument is always a predetermined string. As such, these first 3 arguments need not be sent and can instead be curried into the client side net message listener function. The 4th argument (string) can be then replaced with an enumeration that also serves as an index in a dictionary table. This will allow server owners to translate the text seen to the main language of their server through the dictionary configuration, as opposed to having to go through all the code manually. Doing this will also drastically reduce the net message's size to about 2 bytes. #

This will allow you to send less data while sending the same amount of information. This would also vastly increase your readability, as the name of the enumeration can explain it's effect, while "add" does not. Consider the following:

Unstuck.Enumerations = {
	Debug = {
		OPPERATION_AND = 1,
		NOUN_BOX = 2
	}
}

You can then do the following:

/* ... */
	net.Start( "Unstuck.Debug" )

	//net.WriteString( "add" )
	net.WriteInt( Unstuck.Enumerations.Debug.OPPERATION_ADD, 8 )

	//net.WriteString( "box" )
	net.WriteInt( Unstuck.Enumerations.Debug.NOUN_BOX , 8 )

	net.WriteVector( ply:GetPos()+minBound )
	net.WriteVector( ply:GetPos()+maxBound )
	net.WriteColor( Color(255,150,150) )
	net.Send( ply )
/* ... */

This will show to anyone reading your code that the two enumerations being sent work together. It also means you can send two identical values for different scenarios (eg maybe "add" could mean other things), while having them represented by different variables, allowing anyone reading the code not to have any doubt over which "add" is meant.