diff --git a/lua/lsp-toggle.lua b/lua/lsp-toggle.lua
index 8c2ea0e..9aaddc4 100644
--- a/lua/lsp-toggle.lua
+++ b/lua/lsp-toggle.lua
@@ -5,6 +5,11 @@ local M = {}
 
 ---@param opts? LspToggle.Opts
 function M.setup(opts)
+	if vim.fn.has('nvim-0.11') == 1 then
+		vim.validate('opts', opts, 'table', true, 'LspToggle.Opts?')
+	else
+		vim.validate({ opts = { opts, { 'table', 'nil' } } })
+	end
 	config.setup(opts or {})
 end
 
diff --git a/lua/lsp-toggle/config.lua b/lua/lsp-toggle/config.lua
index ca4247d..d2012d5 100644
--- a/lua/lsp-toggle/config.lua
+++ b/lua/lsp-toggle/config.lua
@@ -5,9 +5,11 @@ local utils = require('lsp-toggle.utils')
 ---@class LspToggle.Opts
 local defaults = {
 	--- If less than `1`, this will revert back to `20`
+	---@type integer
 	max_height = 20,
 
 	--- If less than `1`, this will revert back to `30`
+	---@type integer
 	max_width = 30,
 
 	--- A list of LSP server names to exclude,
@@ -18,11 +20,12 @@ local defaults = {
 	---@type string[]|'double'|'none'|'rounded'|'shadow'|'single'|'solid'
 	border = { '╔', '-', '╗', '║', '╝', '═', '╚', '║' },
 
-	-- Enable/Disable caching
+	--- Enable/Disable caching
+	---@type boolean
 	cache = true,
 }
 
----@class LspToggleConfig
+---@class LspToggle.Config
 local M = {}
 
 ---@type LspToggle.Opts
@@ -30,56 +33,57 @@ M.options = {}
 
 ---@param opts? LspToggle.Opts
 function M.setup(opts)
+	if vim.fn.has('nvim-0.11') == 1 then
+		vim.validate('opts', opts, 'table', true, 'LspToggle.Opts?')
+	else
+		vim.validate({ opts = { opts, { 'table', 'nil' } } })
+	end
 	opts = opts or {}
 
 	M.options = vim.tbl_deep_extend('keep', opts, defaults)
 
-	if M.options.max_height <= 0 then
+	if not M.options.max_height or M.options.max_height <= 0 then
 		M.options.max_height = defaults.max_height
 	end
 
-	if M.options.max_width <= 0 then
+	if not M.options.max_width or M.options.max_width <= 0 then
 		M.options.max_width = defaults.max_width
 	end
 
 	M.setup_autocmds()
 end
 
-function M.setup_autocmds()
-	local load_cache = function()
-		local opts = require('lsp-toggle.config').options
-		if not opts.cache then
-			return
-		end
-		utils.merge_table_pf() -- merge saved data before enabling/disabling clients
-		for _, tb_server in pairs(utils.clients) do
-			vim.lsp.enable(tb_server.server_name, tb_server.enabled)
-		end
+function M.load_cache()
+	if not M.options.cache then
+		return
+	end
+	utils.merge_table_pf() -- merge saved data before enabling/disabling clients
+	for _, tb_server in pairs(utils.clients) do
+		vim.lsp.enable(tb_server.server_name, tb_server.enabled)
+	end
+end
+
+---@param args vim.api.keyset.create_autocmd.callback_args
+local function callback(args)
+	if vim.bo[args.buf].buftype ~= '' then
+		return
 	end
 
-	local augroup = vim.api.nvim_create_augroup('lsp-toggle', { clear = false })
+	fileutils.set_file_path(vim.api.nvim_buf_get_name(args.buf))
+	M.load_cache()
+end
+
+function M.setup_autocmds()
+	local augroup = vim.api.nvim_create_augroup('lsp-toggle', { clear = true })
 
 	vim.api.nvim_create_autocmd('LspAttach', {
 		group = augroup,
-		callback = function()
-			if vim.bo.buftype ~= '' then
-				return
-			end
-
-			fileutils.set_file_path(vim.api.nvim_buf_get_name(0))
-			load_cache()
-		end,
+		callback = callback,
 	})
 
-	vim.api.nvim_create_autocmd({ 'BufEnter', 'BufWinEnter' }, {
-		callback = function(args)
-			if vim.bo[args.buf].buftype ~= '' then
-				return
-			end
-
-			fileutils.set_file_path(vim.api.nvim_buf_get_name(args.buf))
-			load_cache()
-		end,
+	vim.api.nvim_create_autocmd('BufEnter', {
+		group = augroup,
+		callback = callback,
 	})
 
 	vim.api.nvim_create_autocmd('BufLeave', {
diff --git a/lua/lsp-toggle/fileutils.lua b/lua/lsp-toggle/fileutils.lua
index dad6076..22ab0b5 100644
--- a/lua/lsp-toggle/fileutils.lua
+++ b/lua/lsp-toggle/fileutils.lua
@@ -1,3 +1,4 @@
+---@class LspToggleFileUtils
 local M = {}
 
 M.root_dir = vim.fn.stdpath('cache') .. '/lsp-toggle'
@@ -8,6 +9,12 @@ M.file_path = ''
 ---@param str string
 ---@return string hash
 local function djb2(str)
+	if vim.fn.has('nvim-0.11') == 1 then
+		vim.validate('str', str, 'string', false)
+	else
+		vim.validate({ str = { str, 'string' } })
+	end
+
 	local hash = 5381
 	for i = 1, str:len() do
 		local c = str:byte(i)
@@ -17,47 +24,53 @@ local function djb2(str)
 	return tostring(hash)
 end
 
----@param path string
+---@param path? string
 function M.set_file_path(path)
-	M.file_path = path
+	if vim.fn.has('nvim-0.11') == 1 then
+		vim.validate('path', path, 'string', true)
+	else
+		vim.validate({ path = { path, { 'string', 'nil' } } })
+	end
+
+	M.file_path = path or M.file_path
 end
 
 ---@return string
 function M.produce_path()
-	if vim.fn.mkdir(M.root_dir, 'p') ~= 1 then
-		error('[File] Failed to create directory!', vim.log.levels.ERROR)
+	if not vim.fn.isdirectory(M.root_dir) then
+		local dir_fd = vim.uv.fs_mkdir(M.root_dir, tonumber('755', 8))
+		if not dir_fd then
+			error('[FILE] Failed to create directory!', vim.log.levels.ERROR)
+		end
 	end
 
 	return string.format('%s/%s.json', M.root_dir, djb2(M.file_path))
 end
 
----@param data table<string, { enabled: boolean, server_name: string }>
+---@param data table<string, LspToggleUtils.Client>
 ---@return boolean|nil
 function M.save(data)
-	local path = M.produce_path()
-
-	if not path then
-		return nil
+	if vim.fn.has('nvim-0.11') == 1 then
+		vim.validate('data', data, 'table', false, 'table<string, LspToggleUtils.Client>')
+	else
+		vim.validate({ data = { data, 'table' } })
 	end
+	local path = M.produce_path()
 
 	local fd = vim.uv.fs_open(path, 'w', tonumber('644', 8))
 	if not fd then
 		return nil
 	end
 
-	vim.uv.fs_write(fd, vim.fn.json_encode(data))
+	vim.uv.fs_write(fd, vim.fn.json_encode(data), -1)
 	vim.uv.fs_close(fd)
 	return true
 end
 
----@return table<string, { enabled: boolean, server_name: string }>|nil
+---@return table<string, LspToggleUtils.Client>|nil
 function M.load()
 	-- returns lspClients
 	local path = M.produce_path()
-	if not path then
-		return nil
-	end
-
 	local stat = vim.uv.fs_stat(path)
 	if not stat then
 		return nil
@@ -69,7 +82,7 @@ function M.load()
 		return nil
 	end
 
-	local content = vim.uv.fs_read(fd, stat.size)
+	local content = vim.uv.fs_read(fd, stat.size, -1)
 	vim.uv.fs_close(fd)
 	if not content then
 		return nil
@@ -79,19 +92,31 @@ function M.load()
 end
 
 ---@param path? string
+---@return boolean? result
 function M.clear_cache(path)
+	if vim.fn.has('nvim-0.11') == 1 then
+		vim.validate('path', path, 'string', true)
+	else
+		vim.validate({ path = { path, { 'string', 'nil' } } })
+	end
 	path = path or M.root_dir
 
 	local stat = vim.uv.fs_stat(path)
 
 	if not stat or stat.type ~= 'directory' then
-		vim.notify('No cache to clear!', vim.log.levels.WARN)
+		vim.notify('[FILE] No cache to clear!', vim.log.levels.WARN)
 		return nil
 	end
 
 	local dir = vim.uv.fs_scandir(path)
+	if not dir then
+		vim.notify('[FILE] Unable to scan directory!', vim.log.levels.ERROR)
+		return nil
+	end
+
+	local success = true
 
-	while true do
+	while success do
 		---@type string?, 'directory'|'file'?
 		local item, item_type = vim.uv.fs_scandir_next(dir)
 
@@ -102,13 +127,12 @@ function M.clear_cache(path)
 		item = path .. '/' .. item
 
 		if item_type == 'file' then
-			vim.uv.fs_unlink(item)
-		elseif item_type == 'directory' then
-			M.clear_cache(item)
+			success = vim.uv.fs_unlink(item)
 		end
 	end
 
-	return vim.uv.fs_rmdir(path)
+	success = vim.uv.fs_rmdir(path)
+	return success
 end
 
 return M
diff --git a/lua/lsp-toggle/toggle.lua b/lua/lsp-toggle/toggle.lua
index fae4a8e..635da19 100644
--- a/lua/lsp-toggle/toggle.lua
+++ b/lua/lsp-toggle/toggle.lua
@@ -3,14 +3,16 @@ local file = require('lsp-toggle.fileutils')
 local window = require('lsp-toggle.window')
 local utils = require('lsp-toggle.utils')
 
+---@class LspToggle.Toggle
 local M = {}
 
 function M.handle_toggle()
 	local opts = require('lsp-toggle.config').options
+	local win = window.window_id
+	local bufnr = window.window_buf
 
-	local cursor_pos = vim.api.nvim_win_get_cursor(0)
-	local cursor_line = cursor_pos[1]
-	local line_text = vim.api.nvim_buf_get_lines(0, cursor_line - 1, cursor_line, false)[1]
+	local cursor_line = vim.api.nvim_win_get_cursor(win)[1]
+	local line_text = vim.api.nvim_buf_get_lines(bufnr, cursor_line - 1, cursor_line, false)[1]
 
 	local server_name = line_text:sub(5)
 	for name, tb_server in pairs(utils.clients) do
diff --git a/lua/lsp-toggle/utils.lua b/lua/lsp-toggle/utils.lua
index 63af8b3..eb45161 100644
--- a/lua/lsp-toggle/utils.lua
+++ b/lua/lsp-toggle/utils.lua
@@ -1,8 +1,13 @@
 local fileutils = require('lsp-toggle.fileutils')
 
+---@class LspToggleUtils.Client
+---@field enabled boolean
+---@field server_name string
+
+---@class LspToggleUtils
 local M = {}
 
----@type table<string, { enabled: boolean, server_name: string }>
+---@type table<string, LspToggleUtils.Client>
 M.clients = {}
 
 function M.load_all_clients()
@@ -15,7 +20,7 @@ function M.load_all_clients()
 				enabled = vim.lsp.is_enabled(client.name),
 				server_name = client.name,
 			}
-		else
+		elseif vim.list_contains(vim.tbl_keys(M.clients), client.name) then
 			M.clients[client.name] = nil
 		end
 	end
@@ -25,13 +30,13 @@ function M.merge_table_pf()
 	local opts = require('lsp-toggle.config').options
 
 	M.load_all_clients()
-	local file_clients = opts.cache and fileutils.load() or {}
+	local file_clients = opts.cache and (fileutils.load() or {}) or {}
 	local excluded = require('lsp-toggle.config').options.exclude_lsp
 
 	-- merge tables with priority to file
 	for name, client in pairs(M.clients) do
 		local added = false
-		if not vim.tbl_contains(excluded, name) then
+		if not vim.list_contains(excluded, name) then
 			for fname, fclient in pairs(file_clients) do
 				if fname == name then
 					M.clients[fname] = fclient
diff --git a/lua/lsp-toggle/window.lua b/lua/lsp-toggle/window.lua
index eaee717..bc47a2b 100644
--- a/lua/lsp-toggle/window.lua
+++ b/lua/lsp-toggle/window.lua
@@ -1,9 +1,12 @@
 local utils = require('lsp-toggle.utils')
 
+---@class LspToggle.Window
 local M = {}
+
+---@type string[]
 M.out_buf_table = {}
 
----@param clients table<string, { enabled: boolean, server_name: string }>
+---@param clients table<string, LspToggleUtils.Client>
 function M.print_display(clients)
 	M.out_buf_table = {}
 	for _, tb_server in pairs(clients) do
@@ -71,10 +74,12 @@ function M.open_window()
 end
 
 function M.close_window()
-	if M.window_id then
-		vim.api.nvim_win_close(M.window_id, true)
-		M.window_id = nil
+	if not M.window_id then
+		return
 	end
+
+	vim.api.nvim_win_close(M.window_id, true)
+	M.window_id = nil
 end
 
 return M
diff --git a/plugin/lsp-toggle.lua b/plugin/lsp-toggle.lua
index 94cccd1..b5f65c0 100644
--- a/plugin/lsp-toggle.lua
+++ b/plugin/lsp-toggle.lua
@@ -16,8 +16,10 @@ end, {
 })
 
 vim.api.nvim_create_user_command('ToggleLSPClearCache', function()
-	fileutils.clear_cache()
-	vim.notify('Cleared cache, you should probably restart nvim', vim.log.levels.WARN)
+	local notify = fileutils.clear_cache()
+	if notify then
+		vim.notify('Cleared cache, you should probably restart nvim', vim.log.levels.WARN)
+	end
 end, { desc = 'Clear the local cache for lsp-toggle' })
 
 -- vim:ts=4:sts=4:sw=0:noet:ai:si:sta: