diff --git a/src/util/libbl.lua b/src/util/libbl.lua
index 4a0d523..48d65a0 100644
--- a/src/util/libbl.lua
+++ b/src/util/libbl.lua
@@ -446,7 +446,7 @@ local tsMeta = {
 			elseif name:find('::') then
 				local ns, rest = name:match('^([^:]+)::(.+)$')
 				if not ns then error('ts index: invalid name \''..name..'\'', 2) end
-				if not rest:find('::') and tsIsFunction(ns, rest) then
+				if not rest:find('::') and tsIsFunction(ns, rest) then -- tsIsFunction is only defined with one argument
 					error('ts index: can\'t call a namespaced function from lua', 2)
 				else
 					return valFromTs(_bllua_ts.getvar(name), name)
diff --git a/src/util/libts.lua b/src/util/libts.lua
index 2f00ce2..b991021 100644
--- a/src/util/libts.lua
+++ b/src/util/libts.lua
@@ -7,7 +7,11 @@ ts = _bllua_ts
 
 -- Provide limited OS functions
 os = os or {}
+
+---@diagnostic disable-next-line: duplicate-set-field
 function os.time() return math.floor(tonumber(_bllua_ts.call('getSimTime'))/1000) end
+
+---@diagnostic disable-next-line: duplicate-set-field
 function os.clock() return tonumber(_bllua_ts.call('getSimTime'))/1000 end
 
 -- Virtual file class, emulating a file object as returned by io.open
@@ -106,9 +110,10 @@ local function io_open_absolute(fn, mode)
 end
 
 io = io or {}
+---@diagnostic disable-next-line: duplicate-set-field
 function io.open(fn, mode, errn)
 	errn = errn or 1
-	
+
 	-- try to open the file with relative path, otherwise use absolute path
 	local curfn = debug.getfilename(errn + 1) or _bllua_ts.getvar('Con::File')
 	if curfn == '' then curfn = nil end
@@ -116,23 +121,29 @@ function io.open(fn, mode, errn)
 		local relfn = curfn and fn:find('^%./') and
 			curfn:gsub('[^/]+$', '')..fn:gsub('^%./', '')
 		if relfn then
-			local fi, err = io_open_absolute(relfn, mode, errn+1)
+			local fi, err = io_open_absolute(relfn, mode, errn+1) -- defined with 2 args? function io_open_absolute(fn, mode)
 			return fi, err, relfn
 		else
 			return nil, 'Invalid path', fn
 		end
 	else
-		local fi, err = io_open_absolute(fn, mode, errn+1)
+		local fi, err = io_open_absolute(fn, mode, errn+1) -- defined with 2 args but passed 3 in.
 		return fi, err, fn
 	end
 end
+
+---@diagnostic disable-next-line: duplicate-set-field
 function io.lines(fn)
 	local fi, err, fn2 = io.open(fn, nil, 2)
 	if not fi then error('Error opening file \''..fn2..'\': '..err, 2) end
 	return fi:lines()
 end
+
+---@diagnostic disable-next-line: duplicate-set-field
 function io.type(f)
+---@diagnostic disable-next-line: undefined-field
 	if type(f)=='table' and f._is_file then
+---@diagnostic disable-next-line: undefined-field
 		return f._is_open and 'file' or 'closed file'
 	else
 		return _bllua_io_type(f)