diff --git a/.emmyrc.json b/.emmyrc.json
new file mode 100644
index 0000000000..04aa9d3724
--- /dev/null
+++ b/.emmyrc.json
@@ -0,0 +1,14 @@
+{
+  "diagnostics" : {
+    "disable" : [
+      "unnecessary-if"
+    ]
+  },
+  "codeAction": {
+    "insertSpace": true
+  },
+  "strict": {
+    "typeCall": true,
+    "arrayIndex": true
+  }
+}
diff --git a/Makefile b/Makefile
index 29b2644bb8..39b07ee3c6 100644
--- a/Makefile
+++ b/Makefile
@@ -182,3 +182,9 @@ appimage-%:
 	bash scripts/genappimage.sh $*
 
 .PHONY: test clean distclean nvim libnvim cmake deps install appimage checkprefix benchmark $(FORMAT) $(LINT) $(TEST)
+
+.PHONY: emmylua-check
+emmylua-check:
+	-emmylua_check runtime/lua \
+		--config .luarc.json \
+		--config .emmyrc.json
diff --git a/runtime/doc/diagnostic.txt b/runtime/doc/diagnostic.txt
index e0b2b678b0..fa684c246f 100644
--- a/runtime/doc/diagnostic.txt
+++ b/runtime/doc/diagnostic.txt
@@ -430,6 +430,8 @@ Example: >lua
 Lua module: vim.diagnostic                                    *diagnostic-api*
 
 *vim.Diagnostic*
+    Extends: |vim.Diagnostic.Set|
+
                                                         *diagnostic-structure*
 
     Diagnostics use the same indexing as the rest of the Nvim API (i.e.
@@ -437,8 +439,6 @@ Lua module: vim.diagnostic                                    *diagnostic-api*
 
     Fields: ~
       • {bufnr}       (`integer`) Buffer number
-      • {lnum}        (`integer`) The starting line of the diagnostic
-                      (0-indexed)
       • {end_lnum}    (`integer`) The final line of the diagnostic (0-indexed)
       • {col}         (`integer`) The starting column of the diagnostic
                       (0-indexed)
@@ -446,29 +446,27 @@ Lua module: vim.diagnostic                                    *diagnostic-api*
                       (0-indexed)
       • {severity}    (`vim.diagnostic.Severity`) The severity of the
                       diagnostic |vim.diagnostic.severity|
+      • {namespace}?  (`integer`)
+
+*vim.Diagnostic.Set*
+    Diagnostics use the same indexing as the rest of the Nvim API (i.e.
+    0-based rows and columns). |api-indexing|
+
+    Fields: ~
+      • {lnum}        (`integer`) The starting line of the diagnostic
+                      (0-indexed)
+      • {col}?        (`integer`, default: `0`) The starting column of the
+                      diagnostic (0-indexed)
+      • {end_lnum}?   (`integer`, default: `lnum`) The final line of the
+                      diagnostic (0-indexed)
+      • {end_col}?    (`integer`, default: `col`) The final column of the
+                      diagnostic (0-indexed)
+      • {severity}?   (`vim.diagnostic.Severity`, default: `vim.diagnostic.severity.ERROR`)
+                      The severity of the diagnostic |vim.diagnostic.severity|
       • {message}     (`string`) The diagnostic text
       • {source}?     (`string`) The source of the diagnostic
       • {code}?       (`string|integer`) The diagnostic code
       • {user_data}?  (`any`) arbitrary data plugins can add
-      • {namespace}?  (`integer`)
-
-*vim.Diagnostic.Set*
-    Extends: |vim.Diagnostic|
-
-
-    Fields: ~
-      • {bufnr}      (`nil`) Do not set. Will be overridden by
-                     `vim.diagnostic.set()`.
-      • {namespace}  (`nil`) Do not set. Will be overridden by
-                     `vim.diagnostic.set()`.
-      • {col}?       (`integer`, default: `0`) The starting column of the
-                     diagnostic in bytes (0-indexed)
-      • {end_lnum}?  (`integer`, default: same as `lnum`) The final line of
-                     the diagnostic (0-indexed)
-      • {end_col}?   (`integer`, default: same as `col`) The final column of
-                     the diagnostic (0-indexed)
-      • {severity}?  (`vim.diagnostic.Severity`, default: `vim.diagnostic.severity.ERROR`)
-                     The severity of the diagnostic |vim.diagnostic.severity|
 
 *vim.diagnostic.GetOpts*
     A table with the following keys:
diff --git a/runtime/doc/lsp.txt b/runtime/doc/lsp.txt
index 22657fa91c..62d2da07c9 100644
--- a/runtime/doc/lsp.txt
+++ b/runtime/doc/lsp.txt
@@ -1069,7 +1069,7 @@ get_client_by_id({client_id})                     *vim.lsp.get_client_by_id()*
       • {client_id}  (`integer`) client id
 
     Return: ~
-        (`vim.lsp.Client?`) client rpc object
+        (`vim.lsp.Client?`) client rpc object. See |vim.lsp.Client|.
 
 get_clients({filter})                                  *vim.lsp.get_clients()*
     Get active clients.
@@ -1279,7 +1279,8 @@ Lua module: vim.lsp.client                                        *lsp-client*
       • {id}                    (`integer`) The id allocated to the client.
       • {initialized}           (`true?`)
       • {name}                  (`string`) See |vim.lsp.ClientConfig|.
-      • {offset_encoding}       (`string`) See |vim.lsp.ClientConfig|.
+      • {offset_encoding}       (`'utf-8'|'utf-16'|'utf-32'`) See
+                                |vim.lsp.ClientConfig|.
       • {progress}              (`vim.lsp.Client.Progress`) A ring buffer
                                 (|vim.ringbuf()|) containing progress messages
                                 sent by the server. See
@@ -2546,7 +2547,7 @@ make_workspace_params({added}, {removed})
       • {removed}  (`lsp.WorkspaceFolder[]`)
 
     Return: ~
-        (`lsp.WorkspaceFoldersChangeEvent`)
+        (`lsp.DidChangeWorkspaceFoldersParams`)
 
                                         *vim.lsp.util.open_floating_preview()*
 open_floating_preview({contents}, {syntax}, {opts})
diff --git a/runtime/doc/lua.txt b/runtime/doc/lua.txt
index 26b591d077..7867492151 100644
--- a/runtime/doc/lua.txt
+++ b/runtime/doc/lua.txt
@@ -626,10 +626,10 @@ vim.hl.range({bufnr}, {ns}, {higroup}, {start}, {finish}, {opts})
       • {bufnr}    (`integer`) Buffer number to apply highlighting to
       • {ns}       (`integer`) Namespace to add highlight to
       • {higroup}  (`string`) Highlight group to use for highlighting
-      • {start}    (`integer[]|string`) Start of region as a (line, column)
-                   tuple or string accepted by |getpos()|
-      • {finish}   (`integer[]|string`) End of region as a (line, column)
-                   tuple or string accepted by |getpos()|
+      • {start}    (`[integer,integer]|string`) Start of region as a (line,
+                   column) tuple or string accepted by |getpos()|
+      • {finish}   (`[integer,integer]|string`) End of region as a (line,
+                   column) tuple or string accepted by |getpos()|
       • {opts}     (`table?`) A table with the following fields:
                    • {regtype}? (`string`, default: `'v'` i.e. charwise) Type
                      of range. See |getregtype()|
@@ -4684,7 +4684,7 @@ vim.text.indent({size}, {text}, {opts})                    *vim.text.indent()*
     Parameters: ~
       • {size}  (`integer`) Number of spaces.
       • {text}  (`string`) Text to indent.
-      • {opts}  (`{ expandtab?: number }?`)
+      • {opts}  (`{ expandtab?: integer }?`)
 
     Return (multiple): ~
         (`string`) Indented text.
diff --git a/runtime/doc/vimfn.txt b/runtime/doc/vimfn.txt
index d64779af8c..c1436c0d92 100644
--- a/runtime/doc/vimfn.txt
+++ b/runtime/doc/vimfn.txt
@@ -3537,7 +3537,7 @@ getcurpos([{winid}])                                               *getcurpos()*
                   • {winid} (`integer?`)
 
                 Return: ~
-                  (`any`)
+                  (`[integer, integer, integer, integer, integer]`)
 
 getcursorcharpos([{winid}])                                 *getcursorcharpos()*
 		Same as |getcurpos()| but the column number in the returned
@@ -3846,7 +3846,7 @@ getmatches([{win}])                                               *getmatches()*
                   • {win} (`integer?`)
 
                 Return: ~
-                  (`any`)
+                  (`vim.fn.getmatches.ret.item[]`)
 
 getmousepos()                                                    *getmousepos()*
 		Returns a |Dictionary| with the last known position of the
@@ -3952,7 +3952,7 @@ getpos({expr})                                                        *getpos()*
                   • {expr} (`string`)
 
                 Return: ~
-                  (`integer[]`)
+                  (`[integer, integer, integer, integer]`)
 
 getqflist([{what}])                                                *getqflist()*
 		Returns a |List| with all the current quickfix errors.  Each
@@ -4181,9 +4181,9 @@ getregion({pos1}, {pos2} [, {opts}])                               *getregion()*
 <
 
                 Parameters: ~
-                  • {pos1} (`table`)
-                  • {pos2} (`table`)
-                  • {opts} (`table?`)
+                  • {pos1} (`[integer, integer, integer, integer]`)
+                  • {pos2} (`[integer, integer, integer, integer]`)
+                  • {opts} (`{type?:string, exclusive?:boolean}?`)
 
                 Return: ~
                   (`string[]`)
@@ -4221,12 +4221,13 @@ getregionpos({pos1}, {pos2} [, {opts}])                         *getregionpos()*
 					(default: |FALSE|)
 
                 Parameters: ~
-                  • {pos1} (`table`)
-                  • {pos2} (`table`)
-                  • {opts} (`table?`)
+                  • {pos1} (`[integer, integer, integer, integer]`)
+                  • {pos2} (`[integer, integer, integer, integer]`)
+                  • {opts}
+                    (`{type?:string, exclusive?:boolean, eol?:boolean}?`)
 
                 Return: ~
-                  (`integer[][][]`)
+                  (`[ [integer, integer, integer, integer], [integer, integer, integer, integer] ][]`)
 
 getregtype([{regname}])                                           *getregtype()*
 		The result is a String, which is type of register {regname}.
@@ -7852,7 +7853,7 @@ readfile({fname} [, {type} [, {max}]])                              *readfile()*
                   • {max} (`integer?`)
 
                 Return: ~
-                  (`any`)
+                  (`string[]`)
 
 reduce({object}, {func} [, {initial}])                           *reduce()* *E998*
 		{func} is called for every item in {object}, which can be a
@@ -9063,7 +9064,7 @@ setmatches({list} [, {win}])                                      *setmatches()*
 		window ID instead of the current window.
 
                 Parameters: ~
-                  • {list} (`any`)
+                  • {list} (`vim.fn.getmatches.ret.item[]`)
                   • {win} (`integer?`)
 
                 Return: ~
@@ -11742,7 +11743,7 @@ virtcol({expr} [, {list} [, {winid}]])                               *virtcol()*
                   • {winid} (`integer?`)
 
                 Return: ~
-                  (`any`)
+                  (`integer|[integer, integer]`)
 
 virtcol2col({winid}, {lnum}, {col})                              *virtcol2col()*
 		The result is a Number, which is the byte index of the
diff --git a/runtime/lua/tohtml.lua b/runtime/lua/tohtml.lua
index 80892f5c60..019fab6286 100644
--- a/runtime/lua/tohtml.lua
+++ b/runtime/lua/tohtml.lua
@@ -48,7 +48,7 @@
 
 --- @class (private) vim.tohtml.line
 --- @field virt_lines {[integer]:[string,integer][]}
---- @field pre_text string[][]
+--- @field pre_text [string, integer?][]
 --- @field hide? boolean
 --- @field [integer] vim.tohtml.cell? (integer: (1-index, exclusive))
 
@@ -229,7 +229,7 @@ local function cterm_to_hex(colorstr)
     return colorstr
   end
   assert(colorstr ~= '')
-  local color = tonumber(colorstr)
+  local color = tonumber(colorstr) --[[@as integer]]
   assert(color and 0 <= color and color <= 255)
   if cterm_color_cache[color] then
     return cterm_color_cache[color]
@@ -398,7 +398,7 @@ end
 local function styletable_syntax(state)
   for row = state.start, state.end_ do
     local prev_id = 0
-    local prev_col = nil
+    local prev_col --- @type integer?
     for col = 1, #vim.fn.getline(row) + 1 do
       local hlid = vim.fn.synID(row, col, 1)
       hlid = hlid == 0 and 0 or assert(register_hl(state, hlid))
@@ -430,7 +430,7 @@ local function styletable_diff(state)
       break
     end
     local prev_id = 0
-    local prev_col = nil
+    local prev_col --- @type integer?
     for col = 1, #vim.fn.getline(row) do
       local hlid = vim.fn.diff_hlID(row, col)
       hlid = hlid == 0 and 0 or assert(register_hl(state, hlid))
@@ -486,7 +486,7 @@ local function styletable_treesitter(state)
 end
 
 --- @param state vim.tohtml.state
---- @param extmark [integer, integer, integer, vim.api.keyset.set_extmark|any]
+--- @param extmark [integer, integer, integer, vim.api.keyset.extmark_details]
 --- @param namespaces table<integer,string>
 local function _styletable_extmarks_highlight(state, extmark, namespaces)
   if not extmark[4].hl_group then
@@ -548,7 +548,7 @@ local function _styletable_extmarks_virt_text(state, extmark, namespaces)
       else
         style_line_insert_virt_text(styletable[row + 1], col + 1, { i[1], hlid })
       end
-      virt_text_len = virt_text_len + len(i[1])
+      virt_text_len = virt_text_len + len(assert(i[1]))
     end
     if extmark[4].virt_text_pos == 'overlay' then
       styletable_insert_range(state, row + 1, col + 1, row + 1, col + virt_text_len + 1, HIDE_ID)
@@ -588,7 +588,7 @@ local function _styletable_extmarks_virt_lines(state, extmark)
 end
 
 --- @param state vim.tohtml.state
---- @param extmark [integer, integer, integer, vim.api.keyset.set_extmark|any]
+--- @param extmark [integer, integer, integer, vim.api.keyset.extmark_details]
 local function _styletable_extmarks_conceal(state, extmark)
   if not extmark[4].conceal or state.opt.conceallevel == 0 then
     return
@@ -611,6 +611,8 @@ local function styletable_extmarks(state)
   --TODO(altermo) extmarks may have col/row which is outside of the buffer, which could cause an error
   local bufnr = state.bufnr
   local extmarks = vim.api.nvim_buf_get_extmarks(bufnr, -1, 0, -1, { details = true })
+  --- @cast extmarks [integer,integer,integer,vim.api.keyset.extmark_details][]
+
   local namespaces = {} --- @type table<integer, string>
   for ns, ns_id in pairs(vim.api.nvim_get_namespaces()) do
     namespaces[ns_id] = ns
@@ -662,12 +664,12 @@ local function styletable_conceal(state)
       for col = 1, line_len_exclusive do
         --- @type integer,string,integer
         local is_concealed, conceal, hlid = unpack(vim.fn.synconcealed(row, col) --[[@as table]])
-        if is_concealed == 0 then
-          assert(true)
-        elseif not conceals[hlid] then
-          conceals[hlid] = { col, math.min(col + 1, line_len_exclusive), conceal }
-        else
-          conceals[hlid][2] = math.min(col + 1, line_len_exclusive)
+        if is_concealed ~= 0 then
+          if not conceals[hlid] then
+            conceals[hlid] = { col, math.min(col + 1, line_len_exclusive), conceal }
+          else
+            conceals[hlid][2] = math.min(col + 1, line_len_exclusive)
+          end
         end
       end
       for _, v in pairs(conceals) do
@@ -679,9 +681,7 @@ end
 
 --- @param state vim.tohtml.state
 local function styletable_match(state)
-  for _, match in
-    ipairs(vim.fn.getmatches(state.winid) --[[@as (table[])]])
-  do
+  for _, match in ipairs(vim.fn.getmatches(state.winid)) do
     local hlid = register_hl(state, match.group)
     local function range(srow, scol, erow, ecol)
       if match.group == 'Conceal' and state.opt.conceallevel ~= 0 then
@@ -692,19 +692,19 @@ local function styletable_match(state)
     end
     if match.pos1 then
       for key, v in
-        pairs(match --[[@as (table<string,integer[]>)]])
+        pairs(match --[[@as table<string,[integer,integer,integer]>]])
       do
-        if not key:match('^pos(%d+)$') then
-          assert(true)
-        elseif #v == 1 then
-          range(v[1], 1, v[1], #vim.fn.getline(v[1]) + 1)
-        else
-          range(v[1], v[2], v[1], v[3] + v[2])
+        if key:match('^pos(%d+)$') then
+          if #v == 1 then
+            range(v[1], 1, v[1], #vim.fn.getline(v[1]) + 1)
+          else
+            range(v[1], v[2], v[1], v[3] + v[2])
+          end
         end
       end
     else
       for _, v in
-        ipairs(vim.fn.matchbufline(state.bufnr, match.pattern, 1, '$') --[[@as (table[])]])
+        ipairs(vim.fn.matchbufline(state.bufnr, assert(match.pattern), 1, '$') --[[@as (table[])]])
       do
         range(v.lnum, v.byteidx + 1, v.lnum, v.byteidx + 1 + #v.text)
       end
@@ -744,13 +744,15 @@ local function styletable_statuscolumn(state)
     signcolumn = 'auto'
   end
   if signcolumn ~= 'no' then
-    local max = tonumber(signcolumn:match('^%w-:(%d)')) or 1
+    local max = tonumber(signcolumn:match('^%w-:(%d)')) --[[@as integer?]]
+      or 1
     if signcolumn:match('^auto') then
       --- @type table<integer,integer>
       local signcount = {}
       for _, extmark in
         ipairs(vim.api.nvim_buf_get_extmarks(state.bufnr, -1, 0, -1, { details = true }))
       do
+        --- @cast extmark [integer, integer, integer, vim.api.keyset.extmark_details]
         if extmark[4].sign_text then
           signcount[extmark[2]] = (signcount[extmark[2]] or 0) + 1
         end
@@ -770,7 +772,8 @@ local function styletable_statuscolumn(state)
   local foldcolumn = state.opt.foldcolumn
   if foldcolumn ~= '0' then
     if foldcolumn:match('^auto') then
-      local max = tonumber(foldcolumn:match('^%w-:(%d)')) or 1
+      local max = tonumber(foldcolumn:match('^%w-:(%d)')) --[[@as integer?]]
+        or 1
       local maxfold = 0
       vim._with({ buf = state.bufnr }, function()
         for row = state.start, state.end_ do
@@ -782,11 +785,11 @@ local function styletable_statuscolumn(state)
       end)
       minwidth = minwidth + math.min(maxfold, max)
     else
-      minwidth = minwidth + tonumber(foldcolumn)
+      minwidth = minwidth + tonumber(foldcolumn) --[[@as integer]]
     end
   end
 
-  --- @type table<integer,any>
+  --- @type table<integer,vim.api.keyset.eval_statusline_ret>
   local statuses = {}
   for row = state.start, state.end_ do
     local status = vim.api.nvim_eval_statusline(
@@ -798,15 +801,13 @@ local function styletable_statuscolumn(state)
       minwidth = width
     end
     table.insert(statuses, status)
-    --- @type string
   end
   for row, status in pairs(statuses) do
-    --- @type string
     local str = status.str
-    --- @type table[]
     local hls = status.highlights
     for k, v in ipairs(hls) do
-      local text = str:sub(v.start + 1, hls[k + 1] and hls[k + 1].start or nil)
+      local hlsk1 = hls[k + 1]
+      local text = str:sub(v.start + 1, hlsk1 and hlsk1.start or nil)
       if k == #hls then
         text = text .. (' '):rep(minwidth - len(str))
       end
@@ -852,11 +853,9 @@ local function styletable_listchars(state)
     for _, match in
       ipairs(vim.fn.matchbufline(state.bufnr, '\t', 1, '$') --[[@as (table[])]])
     do
-      --- @type integer
-      local tablen = #state.tabstop
-        - ((vim.fn.virtcol({ match.lnum, match.byteidx }, false, state.winid)) % #state.tabstop)
-      --- @type string?
-      local text
+      local vcol = vim.fn.virtcol({ match.lnum, match.byteidx }, false, state.winid) --[[@as integer]]
+      local tablen = #state.tabstop - (vcol % #state.tabstop)
+      local text --- @type string
       if len(listchars.tab) == 3 then
         if tablen == 1 then
           text = utf8_sub(listchars.tab, 3, 3)
@@ -1142,6 +1141,7 @@ local function extend_pre(out, state)
 
   local before = ''
   local after = ''
+  --- @param row integer
   local function loop(row)
     local inside = row <= state.end_ and row >= state.start
     local style_line = styletable[row]
@@ -1168,7 +1168,7 @@ local function extend_pre(out, state)
       pairs(style_line --[[@as table<string,any>]])
     do
       if type(k) == 'number' and k > true_line_len then
-        true_line_len = k
+        true_line_len = k --[[@as integer]]
       end
     end
     for col = 1, true_line_len do
@@ -1305,7 +1305,7 @@ local function opt_to_global_state(opt, title)
     -- Input: "Font,Escape\,comma, Ignore space after comma"
     -- Output: { "Font","Escape,comma","Ignore space after comma" }
     local prev = ''
-    for name in vim.gsplit(vim.o.guifont:match('^[^:]+'), ',', { trimempty = true }) do
+    for name in vim.gsplit(assert(vim.o.guifont:match('^[^:]+')), ',', { trimempty = true }) do
       if vim.endswith(name, '\\') then
         prev = prev .. vim.trim(name:sub(1, -2) .. ',')
       elseif vim.trim(name) ~= '' then
diff --git a/runtime/lua/vim/F.lua b/runtime/lua/vim/F.lua
index 8eb17a4c95..681a92d35c 100644
--- a/runtime/lua/vim/F.lua
+++ b/runtime/lua/vim/F.lua
@@ -37,6 +37,10 @@ function F.ok_or_nil(status, ...)
 end
 
 -- Nil pcall.
+--- @generic T
+--- @param fn  fun(...):T
+--- @param ... T?
+--- @return T
 function F.npcall(fn, ...)
   return F.ok_or_nil(pcall(fn, ...))
 end
diff --git a/runtime/lua/vim/_comment.lua b/runtime/lua/vim/_comment.lua
index c8f7b13659..378d0e2584 100644
--- a/runtime/lua/vim/_comment.lua
+++ b/runtime/lua/vim/_comment.lua
@@ -3,7 +3,7 @@
 ---@field right string Right part of comment
 
 --- Get 'commentstring' at cursor
----@param ref_position integer[]
+---@param ref_position [integer,integer]
 ---@return string
 local function get_commentstring(ref_position)
   local buf_cs = vim.bo.commentstring
@@ -62,7 +62,7 @@ local function get_commentstring(ref_position)
 end
 
 --- Compute comment parts from 'commentstring'
----@param ref_position integer[]
+---@param ref_position [integer,integer]
 ---@return vim._comment.Parts
 local function get_comment_parts(ref_position)
   local cs = get_commentstring(ref_position)
@@ -78,6 +78,7 @@ local function get_comment_parts(ref_position)
 
   -- Structure of 'commentstring': <left part> <%s> <right part>
   local left, right = cs:match('^(.-)%%s(.-)$')
+  assert(left and right)
   return { left = left, right = right }
 end
 
@@ -112,6 +113,7 @@ local function get_lines_info(lines, parts)
   for _, l in ipairs(lines) do
     -- Update lines indent: minimum of all indents except blank lines
     local _, indent_width_cur, indent_cur = l:find('^(%s*)')
+    assert(indent_width_cur and indent_cur)
 
     -- Ignore blank lines completely when making a decision
     if indent_width_cur < l:len() then
@@ -188,7 +190,7 @@ end
 --- Comment/uncomment buffer range
 ---@param line_start integer
 ---@param line_end integer
----@param ref_position? integer[]
+---@param ref_position? [integer, integer]
 local function toggle_lines(line_start, line_end, ref_position)
   ref_position = ref_position or { line_start, 0 }
   local parts = get_comment_parts(ref_position)
diff --git a/runtime/lua/vim/_defaults.lua b/runtime/lua/vim/_defaults.lua
index 52fdfd0aef..7d17c928c3 100644
--- a/runtime/lua/vim/_defaults.lua
+++ b/runtime/lua/vim/_defaults.lua
@@ -26,7 +26,7 @@ do
   end, { desc = 'Edit treesitter query', nargs = '?' })
 
   vim.api.nvim_create_user_command('Open', function(cmd)
-    vim.ui.open(cmd.fargs[1])
+    vim.ui.open(assert(cmd.fargs[1]))
   end, {
     desc = 'Open file with system default handler. See :help vim.ui.open()',
     nargs = 1,
@@ -253,11 +253,11 @@ do
     end, { desc = 'Jump to the previous diagnostic in the current buffer' })
 
     vim.keymap.set('n', ']D', function()
-      vim.diagnostic.jump({ count = math.huge, wrap = false })
+      vim.diagnostic.jump({ count = vim._maxint, wrap = false })
     end, { desc = 'Jump to the last diagnostic in the current buffer' })
 
     vim.keymap.set('n', '[D', function()
-      vim.diagnostic.jump({ count = -math.huge, wrap = false })
+      vim.diagnostic.jump({ count = -vim._maxint, wrap = false })
     end, { desc = 'Jump to the first diagnostic in the current buffer' })
 
     vim.keymap.set('n', '<C-W>d', function()
@@ -466,8 +466,8 @@ do
       amenu disable PopUp.Configure\ Diagnostics
     ]])
 
-    local urls = require('vim.ui')._get_urls()
-    if vim.startswith(urls[1], 'http') then
+    local url = require('vim.ui')._get_urls()[1]
+    if url and vim.startswith(url, 'http') then
       vim.cmd([[amenu enable PopUp.Open\ in\ web\ browser]])
     elseif vim.lsp.get_clients({ bufnr = 0 })[1] then
       vim.cmd([[anoremenu enable PopUp.Go\ to\ definition]])
@@ -595,7 +595,7 @@ do
       { limit = math.abs(count) }
     )
     if #extmarks > 0 then
-      local extmark = extmarks[math.min(#extmarks, math.abs(count))]
+      local extmark = assert(extmarks[math.min(#extmarks, math.abs(count))])
       vim.api.nvim_win_set_cursor(win, { extmark[2] + 1, extmark[3] })
     end
   end
@@ -733,7 +733,7 @@ do
           return nil
         end
 
-        local max = tonumber(string.rep('f', #c), 16)
+        local max = assert(tonumber(string.rep('f', #c), 16))
         return val / max
       end
 
@@ -876,7 +876,7 @@ do
               end
 
               -- The returned SGR sequence should begin with 48:2
-              local sgr = attrs[#attrs]:match('^48:2:([%d:]+)$')
+              local sgr = assert(attrs[#attrs]):match('^48:2:([%d:]+)$')
               if not sgr then
                 return false
               end
@@ -938,13 +938,13 @@ do
         upward = true,
         limit = math.huge,
         -- exrc in cwd already handled from C, thus start in parent directory.
-        path = vim.fs.dirname(vim.uv.cwd()),
+        path = vim.fs.dirname((vim.uv.cwd())),
       })
       for _, file in ipairs(files) do
         local trusted = vim.secure.read(file) --[[@as string|nil]]
         if trusted then
           if vim.endswith(file, '.lua') then
-            loadstring(trusted)()
+            assert(loadstring(trusted))()
           else
             vim.api.nvim_exec2(trusted, {})
           end
diff --git a/runtime/lua/vim/_init_packages.lua b/runtime/lua/vim/_init_packages.lua
index d0bb91114e..21e97c65fe 100644
--- a/runtime/lua/vim/_init_packages.lua
+++ b/runtime/lua/vim/_init_packages.lua
@@ -86,7 +86,7 @@ setmetatable(vim, {
 })
 
 --- <Docs described in |vim.empty_dict()| >
----@private
+---@nodoc
 --- TODO: should be in vim.shared when vim.shared always uses nvim-lua
 --- @diagnostic disable-next-line:duplicate-set-field
 function vim.empty_dict()
diff --git a/runtime/lua/vim/_meta/api.lua b/runtime/lua/vim/_meta/api.lua
index 01f5d08562..a86d52e620 100644
--- a/runtime/lua/vim/_meta/api.lua
+++ b/runtime/lua/vim/_meta/api.lua
@@ -1135,7 +1135,7 @@ function vim.api.nvim_eval(expr) end
 --- - use_tabline: (boolean) Evaluate tabline instead of statusline. When true, {winid}
 ---                          is ignored. Mutually exclusive with {use_winbar}.
 --- - use_statuscol_lnum: (number) Evaluate statuscolumn for this line number instead of statusline.
---- @return table<string,any> # Dict containing statusline information, with these keys:
+--- @return vim.api.keyset.eval_statusline_ret # Dict containing statusline information, with these keys:
 --- - str: (string) Characters that will be displayed on the statusline.
 --- - width: (number) Display width of the statusline.
 --- - highlights: Array containing highlight information of the statusline. Only included when
@@ -2538,7 +2538,7 @@ function vim.api.nvim_win_set_width(window, width) end
 ---               to find out how many buffer lines beyond "start_row" take
 ---               up a certain number of logical lines (returned in
 ---               "end_row" and "end_vcol").
---- @return table<string,any> # Dict containing text height information, with these keys:
+--- @return vim.api.keyset.win_text_height_ret # Dict containing text height information, with these keys:
 --- - all: The total number of screen lines occupied by the range.
 --- - fill: The number of diff filler or virtual lines among them.
 --- - end_row: The row on which the returned height is reached (first row of
diff --git a/runtime/lua/vim/_meta/api_keysets_extra.lua b/runtime/lua/vim/_meta/api_keysets_extra.lua
index fbef6fa3bc..ed93345a2b 100644
--- a/runtime/lua/vim/_meta/api_keysets_extra.lua
+++ b/runtime/lua/vim/_meta/api_keysets_extra.lua
@@ -20,7 +20,7 @@ error('Cannot require a meta file')
 --- @field hl_group? string
 --- @field hl_eol? boolean
 ---
---- @field conceal? boolean
+--- @field conceal? string
 --- @field spell? boolean
 --- @field ui_watched? boolean
 --- @field url? string
@@ -246,3 +246,19 @@ error('Cannot require a meta file')
 --- @field range? integer[]
 --- @field count? integer
 --- @field reg? string
+
+--- @class vim.api.keyset.eval_statusline_ret.highlight
+--- @field start integer
+--- @field group string
+--- @field groups string[]
+
+--- @class vim.api.keyset.eval_statusline_ret
+--- @field str string
+--- @field width integer
+--- @field highlights vim.api.keyset.eval_statusline_ret.highlight[]
+
+--- @class vim.api.keyset.win_text_height_ret
+--- @field all integer
+--- @field fill integer
+--- @field end_row integer
+--- @field end_vcol integer
diff --git a/runtime/lua/vim/_meta/base64.lua b/runtime/lua/vim/_meta/base64.lua
index 8ba59e1703..895ac3334b 100644
--- a/runtime/lua/vim/_meta/base64.lua
+++ b/runtime/lua/vim/_meta/base64.lua
@@ -1,5 +1,7 @@
 --- @meta
 
+vim.base64 = {}
+
 --- Encode {str} using Base64.
 ---
 --- @param str string String to encode
diff --git a/runtime/lua/vim/_meta/builtin_types.lua b/runtime/lua/vim/_meta/builtin_types.lua
index 6886cd6bb7..9c8f2ef603 100644
--- a/runtime/lua/vim/_meta/builtin_types.lua
+++ b/runtime/lua/vim/_meta/builtin_types.lua
@@ -39,6 +39,14 @@
 --- @field pos [integer, integer, integer, integer]
 --- @field file string
 
+--- @class vim.fn.getmatches.ret.item
+--- @field id integer
+--- @field group string
+--- @field pattern? string
+--- @field priority integer
+--- @field conceal? string
+--- @field [string] [integer, integer, integer] all strings of format 'pos%d'
+
 --- @class vim.fn.getmousepos.ret
 --- @field screenrow integer
 --- @field screencol integer
diff --git a/runtime/lua/vim/_meta/vimfn.lua b/runtime/lua/vim/_meta/vimfn.lua
index 2d38a5585e..baffe928b0 100644
--- a/runtime/lua/vim/_meta/vimfn.lua
+++ b/runtime/lua/vim/_meta/vimfn.lua
@@ -3175,7 +3175,7 @@ function vim.fn.getcompletion(pat, type, filtered) end
 --- |winrestview()| for restoring more state.
 ---
 --- @param winid? integer
---- @return any
+--- @return [integer, integer, integer, integer, integer]
 function vim.fn.getcurpos(winid) end
 
 --- Same as |getcurpos()| but the column number in the returned
@@ -3450,7 +3450,7 @@ function vim.fn.getmarklist(buf) end
 --- <
 ---
 --- @param win? integer
---- @return any
+--- @return vim.fn.getmatches.ret.item[]
 function vim.fn.getmatches(win) end
 
 --- Returns a |Dictionary| with the last known position of the
@@ -3551,7 +3551,7 @@ function vim.fn.getpid() end
 --- Also see |getcharpos()|, |getcurpos()| and |setpos()|.
 ---
 --- @param expr string
---- @return integer[]
+--- @return [integer, integer, integer, integer]
 function vim.fn.getpos(expr) end
 
 --- Returns a |List| with all the current quickfix errors.  Each
@@ -3776,9 +3776,9 @@ function vim.fn.getreginfo(regname) end
 ---   \ getpos('v'), getpos('.'), #{ type: mode() })<CR>
 --- <
 ---
---- @param pos1 table
---- @param pos2 table
---- @param opts? table
+--- @param pos1 [integer, integer, integer, integer]
+--- @param pos2 [integer, integer, integer, integer]
+--- @param opts? {type?:string, exclusive?:boolean}
 --- @return string[]
 function vim.fn.getregion(pos1, pos2, opts) end
 
@@ -3813,10 +3813,10 @@ function vim.fn.getregion(pos1, pos2, opts) end
 ---       value of 0 is used for both positions.
 ---       (default: |FALSE|)
 ---
---- @param pos1 table
---- @param pos2 table
---- @param opts? table
---- @return integer[][][]
+--- @param pos1 [integer, integer, integer, integer]
+--- @param pos2 [integer, integer, integer, integer]
+--- @param opts? {type?:string, exclusive?:boolean, eol?:boolean}
+--- @return [ [integer, integer, integer, integer], [integer, integer, integer, integer] ][]
 function vim.fn.getregionpos(pos1, pos2, opts) end
 
 --- The result is a String, which is type of register {regname}.
@@ -7133,7 +7133,7 @@ function vim.fn.readdir(directory, expr) end
 --- @param fname string
 --- @param type? string
 --- @param max? integer
---- @return any
+--- @return string[]
 function vim.fn.readfile(fname, type, max) end
 
 --- {func} is called for every item in {object}, which can be a
@@ -8256,7 +8256,7 @@ function vim.fn.setloclist(nr, list, action, what) end
 --- If {win} is specified, use the window with this number or
 --- window ID instead of the current window.
 ---
---- @param list any
+--- @param list vim.fn.getmatches.ret.item[]
 --- @param win? integer
 --- @return any
 function vim.fn.setmatches(list, win) end
@@ -10693,7 +10693,7 @@ function vim.fn.values(dict) end
 --- @param expr string|any[]
 --- @param list? boolean
 --- @param winid? integer
---- @return any
+--- @return integer|[integer, integer]
 function vim.fn.virtcol(expr, list, winid) end
 
 --- The result is a Number, which is the byte index of the
diff --git a/runtime/lua/vim/_system.lua b/runtime/lua/vim/_system.lua
index e40229de63..23a32fbd49 100644
--- a/runtime/lua/vim/_system.lua
+++ b/runtime/lua/vim/_system.lua
@@ -79,22 +79,19 @@ function SystemObj:_timeout(signal)
   self:kill(signal or SIG.TERM)
 end
 
--- Use max 32-bit signed int value to avoid overflow on 32-bit systems. #31633
-local MAX_TIMEOUT = 2 ^ 31 - 1
-
 --- @param timeout? integer
 --- @return vim.SystemCompleted
 function SystemObj:wait(timeout)
   local state = self._state
 
-  local done = vim.wait(timeout or state.timeout or MAX_TIMEOUT, function()
+  local done = vim.wait(timeout or state.timeout or vim._maxint, function()
     return state.result ~= nil
   end, nil, true)
 
   if not done then
     -- Send sigkill since this cannot be caught
     self:_timeout(SIG.KILL)
-    vim.wait(timeout or state.timeout or MAX_TIMEOUT, function()
+    vim.wait(timeout or state.timeout or vim._maxint, function()
       return state.result ~= nil
     end, nil, true)
   end
diff --git a/runtime/lua/vim/diagnostic.lua b/runtime/lua/vim/diagnostic.lua
index e01b1f2daa..1d395e8c8f 100644
--- a/runtime/lua/vim/diagnostic.lua
+++ b/runtime/lua/vim/diagnostic.lua
@@ -16,29 +16,28 @@ local function get_qf_id_for_title(title)
   return nil
 end
 
---- [diagnostic-structure]()
----
 --- Diagnostics use the same indexing as the rest of the Nvim API (i.e. 0-based
 --- rows and columns). |api-indexing|
---- @class vim.Diagnostic
----
---- Buffer number
---- @field bufnr integer
+--- @class vim.Diagnostic.Set
 ---
 --- The starting line of the diagnostic (0-indexed)
 --- @field lnum integer
 ---
---- The final line of the diagnostic (0-indexed)
---- @field end_lnum integer
----
 --- The starting column of the diagnostic (0-indexed)
---- @field col integer
+--- (default: `0`)
+--- @field col? integer
+---
+--- The final line of the diagnostic (0-indexed)
+--- (default: `lnum`)
+--- @field end_lnum? integer
 ---
 --- The final column of the diagnostic (0-indexed)
---- @field end_col integer
+--- (default: `col`)
+--- @field end_col? integer
 ---
 --- The severity of the diagnostic |vim.diagnostic.severity|
---- @field severity vim.diagnostic.Severity
+--- (default: `vim.diagnostic.severity.ERROR`)
+--- @field severity? vim.diagnostic.Severity
 ---
 --- The diagnostic text
 --- @field message string
@@ -53,32 +52,18 @@ end
 ---
 --- Arbitrary data plugins or users can add
 --- @field user_data? any arbitrary data plugins can add
----
---- @field namespace? integer
 
---- @class vim.Diagnostic.Set : vim.Diagnostic
+--- [diagnostic-structure]()
 ---
---- Do not set. Will be overridden by `vim.diagnostic.set()`.
---- @field bufnr nil
----
---- Do not set. Will be overridden by `vim.diagnostic.set()`.
---- @field namespace nil
----
---- The starting column of the diagnostic in bytes (0-indexed)
---- (default: `0`)
---- @field col? integer
----
---- The final line of the diagnostic (0-indexed)
---- (default: same as `lnum`)
---- @field end_lnum? integer
----
---- The final column of the diagnostic (0-indexed)
---- (default: same as `col`)
---- @field end_col? integer
----
---- The severity of the diagnostic |vim.diagnostic.severity|
---- (default: `vim.diagnostic.severity.ERROR`)
---- @field severity? vim.diagnostic.Severity
+--- Diagnostics use the same indexing as the rest of the Nvim API (i.e. 0-based
+--- rows and columns). |api-indexing|
+--- @class vim.Diagnostic : vim.Diagnostic.Set
+--- @field bufnr integer Buffer number
+--- @field end_lnum integer The final line of the diagnostic (0-indexed)
+--- @field col integer The starting column of the diagnostic (0-indexed)
+--- @field end_col integer The final column of the diagnostic (0-indexed)
+--- @field severity vim.diagnostic.Severity The severity of the diagnostic |vim.diagnostic.severity|
+--- @field namespace? integer
 
 --- Many of the configuration options below accept one of the following:
 --- - `false`: Disable this feature
diff --git a/runtime/lua/vim/filetype.lua b/runtime/lua/vim/filetype.lua
index 276691b080..05f2689813 100644
--- a/runtime/lua/vim/filetype.lua
+++ b/runtime/lua/vim/filetype.lua
@@ -40,7 +40,6 @@ local function starsetf(ft, priority)
   }
 end
 
----@private
 --- Get a line range from the buffer.
 ---@param bufnr integer The buffer to get the lines from
 ---@param start_lnum integer|nil The line number of the first line (inclusive, 1-based)
@@ -55,7 +54,6 @@ function M._getlines(bufnr, start_lnum, end_lnum)
   return api.nvim_buf_get_lines(bufnr, 0, -1, false)
 end
 
----@private
 --- Get a single line from the buffer.
 ---@param bufnr integer The buffer to get the lines from
 ---@param start_lnum integer The line number of the first line (inclusive, 1-based)
@@ -65,7 +63,6 @@ function M._getline(bufnr, start_lnum)
   return api.nvim_buf_get_lines(bufnr, start_lnum - 1, start_lnum, false)[1] or ''
 end
 
----@private
 --- Check whether a string matches any of the given Lua patterns.
 ---
 ---@param s string? The string to check
@@ -83,7 +80,6 @@ function M._findany(s, patterns)
   return false
 end
 
----@private
 --- Get the next non-whitespace line in the buffer.
 ---
 ---@param bufnr integer The buffer to get the line from
@@ -102,7 +98,6 @@ do
   --- @type table<string,vim.regex>
   local regex_cache = {}
 
-  ---@private
   --- Check whether the given string matches the Vim regex pattern.
   --- @param s string?
   --- @param pattern string
@@ -215,7 +210,7 @@ local extension = {
   art = 'art',
   asciidoc = 'asciidoc',
   adoc = 'asciidoc',
-  asa = function(path, bufnr)
+  asa = function(_path, _bufnr)
     if vim.g.filetype_asa then
       return vim.g.filetype_asa
     end
@@ -266,7 +261,7 @@ local extension = {
   bsd = 'bsdl',
   bsdl = 'bsdl',
   bst = 'bst',
-  btm = function(path, bufnr)
+  btm = function(_path, _bufnr)
     return (vim.g.dosbatch_syntax_for_btm and vim.g.dosbatch_syntax_for_btm ~= 0) and 'dosbatch'
       or 'btm'
   end,
@@ -319,7 +314,7 @@ local extension = {
   atg = 'coco',
   recipe = 'conaryrecipe',
   ctags = 'conf',
-  hook = function(path, bufnr)
+  hook = function(_path, bufnr)
     return M._getline(bufnr, 1) == '[Trigger]' and 'confini' or nil
   end,
   nmconnection = 'confini',
@@ -735,7 +730,7 @@ local extension = {
   at = 'm4',
   mc = detect.mc,
   quake = 'm3quake',
-  m4 = function(path, bufnr)
+  m4 = function(path, _bufnr)
     local pathl = path:lower()
     return not (pathl:find('html%.m4$') or pathl:find('fvwm2rc')) and 'm4' or nil
   end,
@@ -1783,12 +1778,12 @@ local filename = {
   ['/etc/pinforc'] = 'pinfo',
   ['/.pinforc'] = 'pinfo',
   ['.povrayrc'] = 'povini',
-  printcap = function(path, bufnr)
+  printcap = function(_path, _bufnr)
     return 'ptcap', function(b)
       vim.b[b].ptcap_type = 'print'
     end
   end,
-  termcap = function(path, bufnr)
+  termcap = function(_path, _bufnr)
     return 'ptcap', function(b)
       vim.b[b].ptcap_type = 'term'
     end
@@ -2029,7 +2024,7 @@ local pattern = {
     ['/etc/modprobe%.'] = starsetf('modconf'),
     ['/etc/modules%.conf$'] = 'modconf',
     ['/etc/modules$'] = 'modconf',
-    ['/etc/modutils/'] = starsetf(function(path, bufnr)
+    ['/etc/modutils/'] = starsetf(function(path, _bufnr)
       if fn.executable(fn.expand(path)) ~= 1 then
         return 'modconf'
       end
@@ -2508,17 +2503,17 @@ local pattern = {
     ['/octave/history$'] = 'octave',
     ['%.opam%.locked$'] = 'opam',
     ['%.opam%.template$'] = 'opam',
-    ['^pacman%.log'] = starsetf(function(path, bufnr)
+    ['^pacman%.log'] = starsetf(function(path, _bufnr)
       return vim.uv.fs_stat(path) and 'pacmanlog' or nil
     end),
-    ['printcap'] = starsetf(function(path, bufnr)
+    ['printcap'] = starsetf(function(_path, _bufnr)
       return require('vim.filetype.detect').printcap('print')
     end),
     ['/queries/.*%.scm$'] = 'query', -- treesitter queries (Neovim only)
     [',v$'] = 'rcs',
     ['^svn%-commit.*%.tmp$'] = 'svn',
     ['%.swift%.gyb$'] = 'swiftgyb',
-    ['termcap'] = starsetf(function(path, bufnr)
+    ['termcap'] = starsetf(function(_path, _bufnr)
       return require('vim.filetype.detect').printcap('term')
     end),
     ['%.t%.html$'] = 'tilde',
@@ -2928,49 +2923,54 @@ function M.match(args)
     name = api.nvim_buf_get_name(bufnr)
   end
 
-  --- @type string?, fun(b: integer)?
-  local ft, on_detect
-
   if name then
     name = normalize_path(name)
 
-    -- First check for the simple case where the full path exists as a key
     local path = abspath(name)
-    ft, on_detect = dispatch(filename[path], path, bufnr)
-    if ft then
-      return ft, on_detect
+    do -- First check for the simple case where the full path exists as a key
+      local ft, on_detect = dispatch(filename[path], path, bufnr)
+      if ft then
+        return ft, on_detect
+      end
     end
 
-    -- Next check against just the file name
     local tail = fn.fnamemodify(name, ':t')
-    ft, on_detect = dispatch(filename[tail], path, bufnr)
-    if ft then
-      return ft, on_detect
+
+    do -- Next check against just the file name
+      local ft, on_detect = dispatch(filename[tail], path, bufnr)
+      if ft then
+        return ft, on_detect
+      end
     end
 
     -- Next, check the file path against available patterns with non-negative priority
     -- Cache match results of all parent patterns to improve performance
     local parent_matches = {}
-    ft, on_detect =
-      match_pattern_sorted(name, path, tail, pattern_sorted_pos, parent_matches, bufnr)
-    if ft then
-      return ft, on_detect
+    do
+      local ft, on_detect =
+        match_pattern_sorted(name, path, tail, pattern_sorted_pos, parent_matches, bufnr)
+      if ft then
+        return ft, on_detect
+      end
     end
 
     -- Next, check file extension
     -- Don't use fnamemodify() with :e modifier here,
     -- as that's empty when there is only an extension.
-    local ext = name:match('%.([^.]-)$') or ''
-    ft, on_detect = dispatch(extension[ext], path, bufnr)
-    if ft then
-      return ft, on_detect
+    do
+      local ext = name:match('%.([^.]-)$') or ''
+      local ft, on_detect = dispatch(extension[ext], path, bufnr)
+      if ft then
+        return ft, on_detect
+      end
     end
 
-    -- Next, check patterns with negative priority
-    ft, on_detect =
-      match_pattern_sorted(name, path, tail, pattern_sorted_neg, parent_matches, bufnr)
-    if ft then
-      return ft, on_detect
+    do -- Next, check patterns with negative priority
+      local ft, on_detect =
+        match_pattern_sorted(name, path, tail, pattern_sorted_neg, parent_matches, bufnr)
+      if ft then
+        return ft, on_detect
+      end
     end
   end
 
@@ -2992,8 +2992,7 @@ function M.match(args)
       -- If name is nil, catch any errors from the contents filetype detection function.
       -- If the function tries to use the filename that is nil then it will fail,
       -- but this enables checks which do not need a filename to still work.
-      local ok
-      ok, ft, on_detect = pcall(
+      local ok, ft, on_detect = pcall(
         require('vim.filetype.detect').match_contents,
         contents,
         name,
diff --git a/runtime/lua/vim/filetype/detect.lua b/runtime/lua/vim/filetype/detect.lua
index c78945ef04..45244af64c 100644
--- a/runtime/lua/vim/filetype/detect.lua
+++ b/runtime/lua/vim/filetype/detect.lua
@@ -1013,7 +1013,7 @@ local function m4(contents)
       return 'm4'
     end
   end
-  if vim.env.TERM == 'amiga' and findany(contents[1]:lower(), { '^;', '^%.bra' }) then
+  if vim.env.TERM == 'amiga' and findany(assert(contents[1]):lower(), { '^;', '^%.bra' }) then
     -- AmigaDos scripts
     return 'amiga'
   end
@@ -1429,10 +1429,10 @@ function M.rules(path)
     return 'javascript'
   else
     local ok, config_lines = pcall(fn.readfile, '/etc/udev/udev.conf')
-    --- @cast config_lines +string[]
     if not ok then
       return 'hog'
     end
+    --- @cast config_lines -string
     local dir = fn.fnamemodify(path, ':h')
     for _, line in ipairs(config_lines) do
       local match = line:match(udev_rules_pattern)
@@ -1678,7 +1678,7 @@ end
 --- @type vim.filetype.mapfn
 function M.tex(path, bufnr)
   local matched, _, format = getline(bufnr, 1):find('^%%&%s*(%a+)')
-  if matched then
+  if matched and format then
     --- @type string
     format = format:lower():gsub('pdf', '', 1)
   elseif path:lower():find('tex/context/.*/.*%.tex') then
@@ -1954,7 +1954,7 @@ local patterns_hashbang = {
 --- @return string?
 --- @return fun(b: integer)?
 local function match_from_hashbang(contents, path, dispatch_extension)
-  local first_line = contents[1]
+  local first_line = assert(contents[1])
   -- Check for a line like "#!/usr/bin/env {options} bash".  Turn it into
   -- "#!/usr/bin/bash" to make matching easier.
   -- Recognize only a few {options} that are commonly used.
@@ -2012,6 +2012,13 @@ local function match_from_hashbang(contents, path, dispatch_extension)
   return dispatch_extension(name)
 end
 
+--- @class vim.filetype.detect.PatternOpts
+--- @field vim_regex? true? use Vim regexes instead of Lua patterns.
+--- @field start_lnum? integer? Start line number for matching, defaults to 1.
+--- @field end_lnum? integer? End line number for matching, defaults to -1 (last line).
+--- @field ignore_case? true ignore case when matching.
+
+-- TODO(lewis6991): split this table into two tables, one for patterns and one for functions.
 local patterns_text = {
   ['^#compdef\\>'] = { 'zsh', { vim_regex = true } },
   ['^#autoload\\>'] = { 'zsh', { vim_regex = true } },
@@ -2144,7 +2151,7 @@ local patterns_text = {
 --- @return string?
 --- @return fun(b: integer)?
 local function match_from_text(contents, path)
-  if contents[1]:find('^:$') then
+  if assert(contents[1]):find('^:$') then
     -- Bourne-like shell scripts: sh ksh bash bash2
     return sh(path, contents)
   elseif
@@ -2160,7 +2167,7 @@ local function match_from_text(contents, path)
   for k, v in pairs(patterns_text) do
     if type(v) == 'string' then
       -- Check the first line only
-      if contents[1]:find(k) then
+      if assert(contents[1]):find(k) then
         return v
       end
     elseif type(v) == 'function' then
@@ -2172,22 +2179,25 @@ local function match_from_text(contents, path)
     else
       --- @cast k string
       local opts = type(v) == 'table' and v[2] or {}
+      --- @cast opts vim.filetype.detect.PatternOpts
       if opts.start_lnum and opts.end_lnum then
         assert(
           not opts.ignore_case,
           'ignore_case=true is ignored when start_lnum is also present, needs refactor'
         )
         for i = opts.start_lnum, opts.end_lnum do
-          if not contents[i] then
+          local line = contents[i]
+          if not line then
             break
-          elseif contents[i]:find(k) then
+          elseif line:find(k) then
             return v[1]
           end
         end
       else
         local line_nr = opts.start_lnum == -1 and #contents or opts.start_lnum or 1
-        if contents[line_nr] then
-          local line = opts.ignore_case and contents[line_nr]:lower() or contents[line_nr]
+        local contents_line_nr = contents[line_nr]
+        if contents_line_nr then
+          local line = opts.ignore_case and contents_line_nr:lower() or contents_line_nr
           if opts.vim_regex and matchregex(line, k) or line:find(k) then
             return v[1]
           end
@@ -2204,7 +2214,7 @@ end
 --- @return string?
 --- @return fun(b: integer)?
 function M.match_contents(contents, path, dispatch_extension)
-  local first_line = contents[1]
+  local first_line = assert(contents[1])
   if first_line:find('^#!') then
     return match_from_hashbang(contents, path, dispatch_extension)
   else
diff --git a/runtime/lua/vim/filetype/options.lua b/runtime/lua/vim/filetype/options.lua
index 2a28b5a8e3..4a396a1b60 100644
--- a/runtime/lua/vim/filetype/options.lua
+++ b/runtime/lua/vim/filetype/options.lua
@@ -70,7 +70,7 @@ local function update_ft_option_cache(filetype)
   end
 end
 
---- @private
+--- @nodoc
 --- @param filetype string Filetype
 --- @param option string Option name
 --- @return string|integer|boolean
diff --git a/runtime/lua/vim/hl.lua b/runtime/lua/vim/hl.lua
index 50345d1dc7..d486984b7c 100644
--- a/runtime/lua/vim/hl.lua
+++ b/runtime/lua/vim/hl.lua
@@ -41,8 +41,8 @@ M.priorities = {
 ---@param bufnr integer Buffer number to apply highlighting to
 ---@param ns integer Namespace to add highlight to
 ---@param higroup string Highlight group to use for highlighting
----@param start integer[]|string Start of region as a (line, column) tuple or string accepted by |getpos()|
----@param finish integer[]|string End of region as a (line, column) tuple or string accepted by |getpos()|
+---@param start [integer,integer]|string Start of region as a (line, column) tuple or string accepted by |getpos()|
+---@param finish [integer,integer]|string End of region as a (line, column) tuple or string accepted by |getpos()|
 ---@param opts? vim.hl.range.Opts
 --- @return uv.uv_timer_t? range_timer A timer which manages how much time the
 --- highlight has left
@@ -98,14 +98,16 @@ function M.range(bufnr, ns, higroup, start, finish, opts)
   })
   -- For non-blockwise selection, use a single extmark.
   if regtype == 'v' or regtype == 'V' then
-    region = { { region[1][1], region[#region][2] } }
+    --- @type [ [integer, integer, integer, integer], [integer, integer, integer, integer]][]
+    region = { { assert(region[1])[1], assert(region[#region])[2] } }
+    local region1 = assert(region[1])
     if
       regtype == 'V'
-      or region[1][2][2] == pos1[2] and pos1[3] == v_maxcol
-      or region[1][2][2] == pos2[2] and pos2[3] == v_maxcol
+      or region1[2][2] == pos1[2] and pos1[3] == v_maxcol
+      or region1[2][2] == pos2[2] and pos2[3] == v_maxcol
     then
-      region[1][2][2] = region[1][2][2] + 1
-      region[1][2][3] = 0
+      region1[2][2] = region1[2][2] + 1
+      region1[2][3] = 0
     end
   end
 
diff --git a/runtime/lua/vim/loader.lua b/runtime/lua/vim/loader.lua
index c7158673fe..d6945f3f02 100644
--- a/runtime/lua/vim/loader.lua
+++ b/runtime/lua/vim/loader.lua
@@ -66,7 +66,7 @@ local indexed = {}
 --- @return uv.fs_stat.result?
 local function fs_stat_cached(path)
   if not fs_stat_cache then
-    return uv.fs_stat(path)
+    return (uv.fs_stat(path))
   end
 
   if not fs_stat_cache[path] then
diff --git a/runtime/lua/vim/lsp.lua b/runtime/lua/vim/lsp.lua
index a3bbf24937..450452157a 100644
--- a/runtime/lua/vim/lsp.lua
+++ b/runtime/lua/vim/lsp.lua
@@ -41,7 +41,6 @@ lsp._resolve_to_request = {
 
 -- TODO improve handling of scratch buffers with LSP attached.
 
----@private
 --- Called by the client when trying to call a method that's not
 --- supported in any of the servers registered for the current buffer.
 ---@param method (vim.lsp.protocol.Method.ClientToServer) name of the method
@@ -54,7 +53,6 @@ function lsp._unsupported_method(method)
   return msg
 end
 
----@private
 ---@param workspace_folders string|lsp.WorkspaceFolder[]?
 ---@return lsp.WorkspaceFolder[]?
 function lsp._get_workspace_folders(workspace_folders)
@@ -78,8 +76,7 @@ local format_line_ending = {
   ['mac'] = '\r',
 }
 
----@private
----@param bufnr (number)
+---@param bufnr integer
 ---@return string
 function lsp._buf_get_line_ending(bufnr)
   return format_line_ending[vim.bo[bufnr].fileformat] or '\n'
@@ -110,10 +107,9 @@ lsp.client_errors = vim.tbl_extend(
   client_error('ON_EXIT_CALLBACK_ERROR')
 )
 
----@private
 --- Returns full text of buffer {bufnr} as a string.
 ---
----@param bufnr (number) Buffer handle, or 0 for current.
+---@param bufnr integer Buffer handle, or 0 for current.
 ---@return string # Buffer text as string.
 function lsp._buf_get_full_text(bufnr)
   local line_ending = lsp._buf_get_line_ending(bufnr)
@@ -284,7 +280,7 @@ end
 ---
 --- Predicate which decides if a client should be re-used. Used on all running clients. The default
 --- implementation re-uses a client if name and root_dir matches.
---- @field reuse_client? fun(client: vim.lsp.Client, config: vim.lsp.ClientConfig): boolean
+--- @field reuse_client? fun(client: vim.lsp.Client, config: vim.lsp.ClientConfig): boolean #
 ---
 --- [lsp-root_dir()]()
 --- Decides the workspace root: the directory where the LSP server will base its workspaceFolders,
@@ -832,7 +828,6 @@ local function is_empty_or_default(bufnr, option)
   return vim.startswith(scriptinfo[1].name, vim.fn.expand('$VIMRUNTIME'))
 end
 
----@private
 ---@param client vim.lsp.Client
 ---@param bufnr integer
 function lsp._set_defaults(client, bufnr)
@@ -1101,8 +1096,8 @@ end
 
 --- Checks if a buffer is attached for a particular client.
 ---
----@param bufnr (integer) Buffer handle, or 0 for current
----@param client_id (integer) the client id
+---@param bufnr integer Buffer handle, or 0 for current
+---@param client_id integer the client id
 function lsp.buf_is_attached(bufnr, client_id)
   return lsp.get_clients({ bufnr = bufnr, id = client_id, _uninitialized = true })[1] ~= nil
 end
@@ -1112,7 +1107,7 @@ end
 ---
 ---@param client_id integer client id
 ---
----@return (nil|vim.lsp.Client) client rpc object
+---@return vim.lsp.Client? client rpc object
 function lsp.get_client_by_id(client_id)
   return all_clients[client_id]
 end
@@ -1207,7 +1202,6 @@ function lsp.get_clients(filter)
   return clients
 end
 
----@private
 ---@deprecated
 function lsp.get_active_clients(filter)
   vim.deprecate('vim.lsp.get_active_clients()', 'vim.lsp.get_clients()', '0.12')
@@ -1263,7 +1257,7 @@ api.nvim_create_autocmd('VimLeavePre', {
   end,
 })
 
----@private
+---@nodoc
 --- Sends an async request for all active clients attached to the
 --- buffer.
 ---
@@ -1401,9 +1395,9 @@ end
 ---
 ---@since 7
 ---
----@param bufnr (integer|nil) The number of the buffer
----@param method (vim.lsp.protocol.Method.ClientToServer.Notification) Name of the request method
----@param params (any) Arguments to send to the server
+---@param bufnr integer? The number of the buffer
+---@param method vim.lsp.protocol.Method.ClientToServer.Notification Name of the request method
+---@param params any Arguments to send to the server
 ---
 ---@return boolean success true if any client returns true; false otherwise
 function lsp.buf_notify(bufnr, method, params)
@@ -1573,7 +1567,7 @@ end
 ---@deprecated Use |vim.lsp.get_client_by_id()| instead.
 ---Checks whether a client is stopped.
 ---
----@param client_id (integer)
+---@param client_id integer
 ---@return boolean stopped true if client is stopped, false otherwise.
 function lsp.client_is_stopped(client_id)
   vim.deprecate('vim.lsp.client_is_stopped()', 'vim.lsp.get_client_by_id()', '0.14')
@@ -1584,7 +1578,7 @@ end
 --- Gets a map of client_id:client pairs for the given buffer, where each value
 --- is a |vim.lsp.Client| object.
 ---
----@param bufnr (integer|nil): Buffer handle, or 0 for current
+---@param bufnr integer? Buffer handle, or 0 for current
 ---@return table result is table of (client_id, client) pairs
 ---@deprecated Use |vim.lsp.get_clients()| instead.
 function lsp.buf_get_clients(bufnr)
@@ -1630,7 +1624,7 @@ function lsp.get_log_path()
   return log.get_filename()
 end
 
----@private
+---@nodoc
 --- Invokes a function for each LSP client attached to a buffer.
 ---
 ---@param bufnr integer Buffer number
diff --git a/runtime/lua/vim/lsp/_tagfunc.lua b/runtime/lua/vim/lsp/_tagfunc.lua
index 554f0cb991..3122eeee2e 100644
--- a/runtime/lua/vim/lsp/_tagfunc.lua
+++ b/runtime/lua/vim/lsp/_tagfunc.lua
@@ -6,7 +6,7 @@ local ms = lsp.protocol.Methods
 ---@param name string
 ---@param range lsp.Range
 ---@param uri string
----@param position_encoding string
+---@param position_encoding 'utf-8'|'utf-16'|'utf-32'
 ---@return {name: string, filename: string, cmd: string, kind?: string}
 local function mk_tag_item(name, range, uri, position_encoding)
   local bufnr = vim.uri_to_bufnr(uri)
@@ -32,7 +32,7 @@ local function query_definition(pattern)
 
   --- @param range lsp.Range
   --- @param uri string
-  --- @param position_encoding string
+  ---@param position_encoding 'utf-8'|'utf-16'|'utf-32'
   local add = function(range, uri, position_encoding)
     table.insert(results, mk_tag_item(pattern, range, uri, position_encoding))
   end
diff --git a/runtime/lua/vim/lsp/buf.lua b/runtime/lua/vim/lsp/buf.lua
index aac9965f42..ca70789506 100644
--- a/runtime/lua/vim/lsp/buf.lua
+++ b/runtime/lua/vim/lsp/buf.lua
@@ -545,7 +545,7 @@ function M.format(opts)
   end
 
   local passed_multiple_ranges = (range and #range ~= 0 and type(range[1]) == 'table')
-  local method ---@type string
+  local method ---@type vim.lsp.protocol.Method.ClientToServer
   if passed_multiple_ranges then
     method = ms.textDocument_rangesFormatting
   elseif range then
@@ -579,10 +579,11 @@ function M.format(opts)
 
     local ret = params --[[@as lsp.DocumentFormattingParams|lsp.DocumentRangeFormattingParams|lsp.DocumentRangesFormattingParams]]
     if passed_multiple_ranges then
+      --- @cast range {start:[integer,integer],end:[integer, integer]}[]
       ret = params --[[@as lsp.DocumentRangesFormattingParams]]
-      --- @cast range {start:[integer,integer],end:[integer, integer]}
       ret.ranges = vim.tbl_map(to_lsp_range, range)
     elseif range then
+      --- @cast range {start:[integer,integer],end:[integer, integer]}
       ret = params --[[@as lsp.DocumentRangeFormattingParams]]
       ret.range = to_lsp_range(range)
     end
@@ -660,7 +661,7 @@ function M.rename(new_name, opts)
   local cword = vim.fn.expand('<cword>')
 
   --- @param range lsp.Range
-  --- @param position_encoding string
+  --- @param position_encoding 'utf-8'|'utf-16'|'utf-32'
   local function get_text_at_range(range, position_encoding)
     return api.nvim_buf_get_text(
       bufnr,
@@ -1199,7 +1200,7 @@ local function on_code_action_results(results, opts)
       return title
     end
 
-    local source = lsp.get_client_by_id(item.ctx.client_id).name
+    local source = assert(lsp.get_client_by_id(item.ctx.client_id)).name
     return ('%s [%s]'):format(title, source)
   end
 
diff --git a/runtime/lua/vim/lsp/client.lua b/runtime/lua/vim/lsp/client.lua
index 00fece8985..47b6e5c145 100644
--- a/runtime/lua/vim/lsp/client.lua
+++ b/runtime/lua/vim/lsp/client.lua
@@ -176,7 +176,7 @@ local validate = vim.validate
 --- @field name string
 ---
 --- See [vim.lsp.ClientConfig].
---- @field offset_encoding string
+--- @field offset_encoding 'utf-8'|'utf-16'|'utf-32'
 ---
 --- A ring buffer (|vim.ringbuf()|) containing progress messages
 --- sent by the server.
@@ -440,16 +440,16 @@ function Client.create(config)
   --- @type vim.lsp.rpc.Dispatchers
   local dispatchers = {
     notification = function(...)
-      return self:_notification(...)
+      self:_notification(...)
     end,
     server_request = function(...)
       return self:_server_request(...)
     end,
     on_error = function(...)
-      return self:_on_error(...)
+      self:_on_error(...)
     end,
     on_exit = function(...)
-      return self:_on_exit(...)
+      self:_on_exit(...)
     end,
   }
 
@@ -597,7 +597,7 @@ end
 
 --- @private
 --- @param id integer
---- @param req_type 'pending'|'complete'|'cancel'|
+--- @param req_type 'pending'|'complete'|'cancel'
 --- @param bufnr? integer (only required for req_type='pending')
 --- @param method? string (only required for req_type='pending')
 function Client:_process_request(id, req_type, bufnr, method)
diff --git a/runtime/lua/vim/lsp/codelens.lua b/runtime/lua/vim/lsp/codelens.lua
index e36d8fee27..02da7fc367 100644
--- a/runtime/lua/vim/lsp/codelens.lua
+++ b/runtime/lua/vim/lsp/codelens.lua
@@ -258,20 +258,22 @@ end
 ---@param result lsp.CodeLens[]
 ---@param ctx lsp.HandlerContext
 function M.on_codelens(err, result, ctx)
+  local bufnr = assert(ctx.bufnr)
+
   if err then
-    active_refreshes[assert(ctx.bufnr)] = nil
+    active_refreshes[bufnr] = nil
     log.error('codelens', err)
     return
   end
 
-  M.save(result, ctx.bufnr, ctx.client_id)
+  M.save(result, bufnr, ctx.client_id)
 
   -- Eager display for any resolved (and unresolved) lenses and refresh them
   -- once resolved.
-  M.display(result, ctx.bufnr, ctx.client_id)
-  resolve_lenses(result, ctx.bufnr, ctx.client_id, function()
-    active_refreshes[assert(ctx.bufnr)] = nil
-    M.display(result, ctx.bufnr, ctx.client_id)
+  M.display(result, bufnr, ctx.client_id)
+  resolve_lenses(result, bufnr, ctx.client_id, function()
+    active_refreshes[bufnr] = nil
+    M.display(result, bufnr, ctx.client_id)
   end)
 end
 
diff --git a/runtime/lua/vim/lsp/completion.lua b/runtime/lua/vim/lsp/completion.lua
index 60574a94cd..ac8099de1b 100644
--- a/runtime/lua/vim/lsp/completion.lua
+++ b/runtime/lua/vim/lsp/completion.lua
@@ -38,7 +38,7 @@ local lsp = vim.lsp
 local protocol = lsp.protocol
 local ms = protocol.Methods
 
-local rtt_ms = 50
+local rtt_ms = 50.0
 local ns_to_ms = 0.000001
 
 --- @alias vim.lsp.CompletionResult lsp.CompletionList | lsp.CompletionItem[]
@@ -92,7 +92,7 @@ local completion_timer = nil
 
 --- @return uv.uv_timer_t
 local function new_timer()
-  return assert(vim.uv.new_timer())
+  return (assert(vim.uv.new_timer()))
 end
 
 local function reset_timer()
@@ -110,7 +110,7 @@ end
 local function exp_avg(window, warmup)
   local count = 0
   local sum = 0
-  local value = 0
+  local value = 0.0
 
   return function(sample)
     if count < warmup then
@@ -278,7 +278,6 @@ end
 --- Turns the result of a `textDocument/completion` request into vim-compatible
 --- |complete-items|.
 ---
---- @private
 --- @param result vim.lsp.CompletionResult Result of `textDocument/completion`
 --- @param prefix string prefix to filter the completion items
 --- @param client_id integer? Client ID
@@ -365,7 +364,7 @@ end
 --- @param lnum integer 0-indexed
 --- @param line string
 --- @param items lsp.CompletionItem[]
---- @param encoding string
+--- @param encoding 'utf-8'|'utf-16'|'utf-32'
 --- @return integer?
 local function adjust_start_col(lnum, line, items, encoding)
   local min_start_char = nil
@@ -384,7 +383,6 @@ local function adjust_start_col(lnum, line, items, encoding)
   end
 end
 
---- @private
 --- @param line string line content
 --- @param lnum integer 0-indexed line number
 --- @param cursor_col integer
@@ -392,7 +390,7 @@ end
 --- @param client_start_boundary integer 0-indexed word boundary
 --- @param server_start_boundary? integer 0-indexed word boundary, based on textEdit.range.start.character
 --- @param result vim.lsp.CompletionResult
---- @param encoding string
+--- @param encoding 'utf-8'|'utf-16'|'utf-32'
 --- @return table[] matches
 --- @return integer? server_start_boundary
 function M._convert_results(
@@ -487,7 +485,7 @@ local function trigger(bufnr, clients, ctx)
   local line = api.nvim_get_current_line()
   local line_to_cursor = line:sub(1, cursor_col)
   local word_boundary = vim.fn.match(line_to_cursor, '\\k*$')
-  local start_time = vim.uv.hrtime()
+  local start_time = vim.uv.hrtime() --[[@as integer]]
   Context.last_request_time = start_time
 
   local cancel_request = request(clients, bufnr, win, ctx, function(responses)
@@ -557,7 +555,7 @@ local function on_insert_char_pre(handle)
       else
         completion_timer = new_timer()
         completion_timer:start(
-          debounce_ms,
+          math.floor(debounce_ms),
           0,
           vim.schedule_wrap(function()
             M.get({ ctx = ctx })
diff --git a/runtime/lua/vim/lsp/diagnostic.lua b/runtime/lua/vim/lsp/diagnostic.lua
index 1ea0123b1b..bdddb704a5 100644
--- a/runtime/lua/vim/lsp/diagnostic.lua
+++ b/runtime/lua/vim/lsp/diagnostic.lua
@@ -11,25 +11,28 @@ local augroup = api.nvim_create_augroup('nvim.lsp.diagnostic', {})
 ---@class (private) vim.lsp.diagnostic.BufState
 ---@field enabled boolean Whether diagnostics are enabled for this buffer
 ---@field client_result_id table<integer, string?> Latest responded `resultId`
----@type table<integer, vim.lsp.diagnostic.BufState?>
+
+---@type table<integer,vim.lsp.diagnostic.BufState>
 local bufstates = {}
 
 local DEFAULT_CLIENT_ID = -1
 
 ---@param severity lsp.DiagnosticSeverity
+---@return vim.diagnostic.Severity
 local function severity_lsp_to_vim(severity)
   if type(severity) == 'string' then
-    severity = protocol.DiagnosticSeverity[severity] --- @type integer
+    return protocol.DiagnosticSeverity[severity] --[[@as vim.diagnostic.Severity]]
   end
   return severity
 end
 
+---@param severity vim.diagnostic.Severity|vim.diagnostic.SeverityName
 ---@return lsp.DiagnosticSeverity
 local function severity_vim_to_lsp(severity)
   if type(severity) == 'string' then
-    severity = vim.diagnostic.severity[severity] --- @type integer
+    return vim.diagnostic.severity[severity]
   end
-  return severity
+  return severity --[[@as lsp.DiagnosticSeverity]]
 end
 
 ---@param bufnr integer
@@ -186,10 +189,9 @@ function M.get_namespace(client_id, is_pull)
   local client = vim.lsp.get_client_by_id(client_id)
   if is_pull then
     local server_id =
-      vim.tbl_get((client or {}).server_capabilities, 'diagnosticProvider', 'identifier')
-    local key = string.format('%d:%s', client_id, server_id or 'nil')
-    local name = string.format(
-      'nvim.lsp.%s.%d.%s',
+      vim.tbl_get((client or {}).server_capabilities or {}, 'diagnosticProvider', 'identifier')
+    local key = ('%d:%s'):format(client_id, server_id or 'nil')
+    local name = ('nvim.lsp.%s.%d.%s'):format(
       client and client.name or 'unknown',
       client_id,
       server_id or 'nil'
@@ -200,15 +202,15 @@ function M.get_namespace(client_id, is_pull)
       _client_pull_namespaces[key] = ns
     end
     return ns
-  else
-    local name = string.format('nvim.lsp.%s.%d', client and client.name or 'unknown', client_id)
-    local ns = _client_push_namespaces[client_id]
-    if not ns then
-      ns = api.nvim_create_namespace(name)
-      _client_push_namespaces[client_id] = ns
-    end
-    return ns
   end
+
+  local ns = _client_push_namespaces[client_id]
+  if not ns then
+    local name = ('nvim.lsp.%s.%d'):format(client and client.name or 'unknown', client_id)
+    ns = api.nvim_create_namespace(name)
+    _client_push_namespaces[client_id] = ns
+  end
+  return ns
 end
 
 --- @param uri string
@@ -227,9 +229,7 @@ local function handle_diagnostics(uri, client_id, diagnostics, is_pull)
     return
   end
 
-  if client_id == nil then
-    client_id = DEFAULT_CLIENT_ID
-  end
+  client_id = client_id or DEFAULT_CLIENT_ID
 
   local namespace = M.get_namespace(client_id, is_pull)
 
@@ -380,7 +380,6 @@ end
 
 --- Enable pull diagnostics for a buffer
 ---@param bufnr (integer) Buffer handle, or 0 for current
----@private
 function M._enable(bufnr)
   bufnr = vim._resolve_bufnr(bufnr)
 
diff --git a/runtime/lua/vim/lsp/document_color.lua b/runtime/lua/vim/lsp/document_color.lua
index 039b8debff..f721f1536d 100644
--- a/runtime/lua/vim/lsp/document_color.lua
+++ b/runtime/lua/vim/lsp/document_color.lua
@@ -40,7 +40,13 @@ local document_color_opts = { style = 'background' }
 --- @param color string
 local function get_contrast_color(color)
   local r_s, g_s, b_s = color:match('^#(%x%x)(%x%x)(%x%x)$')
+  if not (r_s and g_s and b_s) then
+    error('Invalid color format: ' .. color)
+  end
   local r, g, b = tonumber(r_s, 16), tonumber(g_s, 16), tonumber(b_s, 16)
+  if not (r and g and b) then
+    error('Invalid color format: ' .. color)
+  end
 
   -- Source: https://www.w3.org/TR/WCAG21/#dfn-relative-luminance
   -- Using power 2.2 is a close approximation to full piecewise transform
@@ -185,7 +191,7 @@ local function buf_enable(bufnr)
   api.nvim_buf_attach(bufnr, false, {
     on_reload = function(_, buf)
       buf_clear(buf)
-      if bufstates[buf].enabled then
+      if assert(bufstates[buf]).enabled then
         M._buf_refresh(buf)
       end
     end,
@@ -203,7 +209,7 @@ local function buf_enable(bufnr)
 
       if
         (method == ms.textDocument_didChange or method == ms.textDocument_didOpen)
-        and bufstates[args.buf].enabled
+        and assert(bufstates[args.buf]).enabled
       then
         M._buf_refresh(args.buf, args.data.client_id)
       end
@@ -254,7 +260,7 @@ function M.is_enabled(bufnr)
     reset_bufstate(bufnr, false)
   end
 
-  return bufstates[bufnr].enabled
+  return assert(bufstates[bufnr]).enabled
 end
 
 --- Enables document highlighting from the given language client in the given buffer.
diff --git a/runtime/lua/vim/lsp/handlers.lua b/runtime/lua/vim/lsp/handlers.lua
index 796b6503b1..a85b291285 100644
--- a/runtime/lua/vim/lsp/handlers.lua
+++ b/runtime/lua/vim/lsp/handlers.lua
@@ -241,7 +241,7 @@ end
 ---
 --- The returned function has an optional {config} parameter that accepts |vim.lsp.ListOpts|
 ---
----@param map_result fun(resp, bufnr: integer, position_encoding: 'utf-8'|'utf-16'|'utf-32'): table to convert the response
+---@param map_result fun(resp: any, bufnr: integer, position_encoding: 'utf-8'|'utf-16'|'utf-32'): table to convert the response
 ---@param entity string name of the resource used in a `not found` error message
 ---@param title_fn fun(ctx: lsp.HandlerContext): string Function to call to generate list title
 ---@return lsp.Handler
diff --git a/runtime/lua/vim/lsp/inlay_hint.lua b/runtime/lua/vim/lsp/inlay_hint.lua
index 97ac09f69e..592c89ae67 100644
--- a/runtime/lua/vim/lsp/inlay_hint.lua
+++ b/runtime/lua/vim/lsp/inlay_hint.lua
@@ -15,6 +15,7 @@ local globalstate = {
 ---@field version? integer
 ---@field client_hints? table<integer, table<integer, lsp.InlayHint[]>> client_id -> (lnum -> hints)
 ---@field applied table<integer, integer> Last version of hints applied to this line
+
 ---@type table<integer, vim.lsp.inlay_hint.bufstate>
 local bufstates = vim.defaulttable(function(_)
   return setmetatable({ applied = {} }, {
diff --git a/runtime/lua/vim/lsp/rpc.lua b/runtime/lua/vim/lsp/rpc.lua
index 446a98f7e2..0e082d0f80 100644
--- a/runtime/lua/vim/lsp/rpc.lua
+++ b/runtime/lua/vim/lsp/rpc.lua
@@ -36,6 +36,7 @@ end
 local M = {}
 
 --- Mapping of error codes used by the client
+--- @enum vim.lsp.rpc.ClientErrors
 local client_errors = {
   INVALID_SERVER_MESSAGE = 1,
   INVALID_SERVER_JSON = 2,
@@ -150,6 +151,7 @@ local default_dispatchers = {
 
 local strbuffer = require('vim._stringbuffer')
 
+--- @async
 local function request_parser_loop()
   local buf = strbuffer.new()
   while true do
@@ -279,7 +281,7 @@ function Client:request(method, params, callback, notify_reply_callback)
 end
 
 ---@package
----@param errkind integer
+---@param errkind vim.lsp.rpc.ClientErrors
 ---@param ... any
 function Client:on_error(errkind, ...)
   assert(M.client_errors[errkind])
@@ -375,7 +377,7 @@ function Client:handle_body(body)
     -- This works because we are expecting vim.NIL here
   elseif decoded.id and (decoded.result ~= vim.NIL or decoded.error ~= vim.NIL) then
     -- We sent a number, so we expect a number.
-    local result_id = assert(tonumber(decoded.id), 'response id must be a number')
+    local result_id = assert(tonumber(decoded.id), 'response id must be a number') --[[@as integer]]
 
     -- Notify the user that a response was received for the request
     local notify_reply_callback = self.notify_reply_callbacks[result_id]
diff --git a/runtime/lua/vim/lsp/semantic_tokens.lua b/runtime/lua/vim/lsp/semantic_tokens.lua
index 5f60b732de..6cb1547169 100644
--- a/runtime/lua/vim/lsp/semantic_tokens.lua
+++ b/runtime/lua/vim/lsp/semantic_tokens.lua
@@ -90,6 +90,7 @@ end
 
 --- Converts a raw token list to a list of highlight ranges used by the on_win callback
 ---
+---@async
 ---@param data integer[]
 ---@param bufnr integer
 ---@param client vim.lsp.Client
@@ -326,6 +327,7 @@ end
 --- Finally, a redraw command is issued to force nvim to redraw the screen to
 --- pick up changed highlight tokens.
 ---
+---@async
 ---@param response lsp.SemanticTokens|lsp.SemanticTokensDelta
 ---@private
 function STHighlighter:process_response(response, client, version)
@@ -491,7 +493,7 @@ function STHighlighter:on_win(topline, botline)
       local is_folded, foldend
 
       for i = first, last do
-        local token = highlights[i]
+        local token = assert(highlights[i])
 
         is_folded, foldend = check_fold(token.line + 1, foldend)
 
diff --git a/runtime/lua/vim/lsp/sync.lua b/runtime/lua/vim/lsp/sync.lua
index 621f63b25f..a7c688ee89 100644
--- a/runtime/lua/vim/lsp/sync.lua
+++ b/runtime/lua/vim/lsp/sync.lua
@@ -52,10 +52,11 @@ local str_utf_end = vim.str_utf_end
 -- utf-8 index and either the utf-16, or utf-32 index.
 ---@param line string the line to index into
 ---@param byte integer the byte idx
----@param position_encoding string utf-8|utf-16|utf-32|nil (default: utf-8)
+---@param position_encoding 'utf-8'|'utf-16'|'utf-32'? (default: utf-8)
 ---@return integer byte_idx of first change position
 ---@return integer char_idx of first change position
 local function align_end_position(line, byte, position_encoding)
+  position_encoding = position_encoding or 'utf-8'
   local char --- @type integer
   -- If on the first byte, or an empty string: the trivial case
   if byte == 1 or #line == 0 then
@@ -93,7 +94,7 @@ end
 ---@param firstline integer firstline from on_lines, adjusted to 1-index
 ---@param lastline integer lastline from on_lines, adjusted to 1-index
 ---@param new_lastline integer new_lastline from on_lines, adjusted to 1-index
----@param position_encoding string utf-8|utf-16|utf-32|nil (fallback to utf-8)
+---@param position_encoding 'utf-8'|'utf-16'|'utf-32'? (default: utf-8)
 ---@return vim.lsp.sync.Range result table include line_idx, byte_idx, and char_idx of first change position
 local function compute_start_range(
   prev_lines,
@@ -103,6 +104,8 @@ local function compute_start_range(
   new_lastline,
   position_encoding
 )
+  position_encoding = position_encoding or 'utf-8'
+
   local char_idx --- @type integer?
   local byte_idx --- @type integer?
   -- If firstline == lastline, no existing text is changed. All edit operations
@@ -130,8 +133,8 @@ local function compute_start_range(
     return { line_idx = firstline, byte_idx = 1, char_idx = 1 }
   end
 
-  local prev_line = prev_lines[firstline]
-  local curr_line = curr_lines[firstline]
+  local prev_line = assert(prev_lines[firstline])
+  local curr_line = assert(curr_lines[firstline])
 
   -- Iterate across previous and current line containing first change
   -- to find the first different byte.
@@ -174,7 +177,7 @@ end
 ---@param firstline integer
 ---@param lastline integer
 ---@param new_lastline integer
----@param position_encoding string
+---@param position_encoding 'utf-8'|'utf-16'|'utf-32'
 ---@return vim.lsp.sync.Range prev_end_range
 ---@return vim.lsp.sync.Range curr_end_range
 local function compute_end_range(
@@ -189,7 +192,7 @@ local function compute_end_range(
   -- A special case for the following `firstline == new_lastline` case where lines are deleted.
   -- Even if the buffer has become empty, nvim behaves as if it has an empty line with eol.
   if #curr_lines == 1 and curr_lines[1] == '' then
-    local prev_line = prev_lines[lastline - 1]
+    local prev_line = assert(prev_lines[lastline - 1])
     return {
       line_idx = lastline - 1,
       byte_idx = #prev_line + 1,
@@ -219,8 +222,8 @@ local function compute_end_range(
   local prev_line_idx = lastline - 1
   local curr_line_idx = new_lastline - 1
 
-  local prev_line = prev_lines[lastline - 1]
-  local curr_line = curr_lines[new_lastline - 1]
+  local prev_line = assert(prev_lines[lastline - 1])
+  local curr_line = assert(curr_lines[new_lastline - 1])
 
   local prev_line_length = #prev_line
   local curr_line_length = #curr_line
@@ -284,8 +287,8 @@ end
 
 --- Get the text of the range defined by start and end line/column
 ---@param lines table list of lines
----@param start_range table table returned by first_difference
----@param end_range table new_end_range returned by last_difference
+---@param start_range vim.lsp.sync.Range table returned by first_difference
+---@param end_range vim.lsp.sync.Range new_end_range returned by last_difference
 ---@return string text extracted from defined region
 local function extract_text(lines, start_range, end_range, line_ending)
   if not lines[start_range.line_idx] then
@@ -326,7 +329,7 @@ end
 ---@param lines string[]
 ---@param start_range vim.lsp.sync.Range
 ---@param end_range vim.lsp.sync.Range
----@param position_encoding string
+---@param position_encoding 'utf-8'|'utf-16'|'utf-32'
 ---@param line_ending string
 ---@return integer
 local function compute_range_length(lines, start_range, end_range, position_encoding, line_ending)
@@ -352,7 +355,9 @@ local function compute_range_length(lines, start_range, end_range, position_enco
   for idx = start_range.line_idx + 1, end_range.line_idx - 1 do
     -- Length full line plus newline character
     if #lines[idx] > 0 then
-      range_length = range_length + str_utfindex(lines[idx], position_encoding) + #line_ending
+      range_length = range_length
+        + str_utfindex(assert(lines[idx]), position_encoding)
+        + #line_ending
     else
       range_length = range_length + line_ending_length
     end
@@ -372,7 +377,7 @@ end
 ---@param firstline integer line to begin search for first difference
 ---@param lastline integer line to begin search in old_lines for last difference
 ---@param new_lastline integer line to begin search in new_lines for last difference
----@param position_encoding string encoding requested by language server
+---@param position_encoding 'utf-8'|'utf-16'|'utf-32' encoding requested by language server
 ---@param line_ending string
 ---@return lsp.TextDocumentContentChangeEvent : see https://microsoft.github.io/language-server-protocol/specification/#textDocumentContentChangeEvent
 function M.compute_diff(
diff --git a/runtime/lua/vim/lsp/util.lua b/runtime/lua/vim/lsp/util.lua
index 1f83d71edf..277bb8211b 100644
--- a/runtime/lua/vim/lsp/util.lua
+++ b/runtime/lua/vim/lsp/util.lua
@@ -68,6 +68,7 @@ local function get_border_size(opts)
   end
 
   --- @param e string
+  --- @return integer
   local function border_height(e)
     return #e > 0 and 1 or 0
   end
@@ -133,9 +134,9 @@ function M.set_lines(lines, A, B, new_lines)
     error('Invalid range: ' .. vim.inspect({ A = A, B = B, #lines, new_lines }))
   end
   local prefix = ''
-  local suffix = lines[i_n]:sub(B[2] + 1)
+  local suffix = assert(lines[i_n]):sub(B[2] + 1)
   if A[2] > 0 then
-    prefix = lines[i_0]:sub(1, A[2])
+    prefix = assert(lines[i_0]):sub(1, A[2])
   end
   local n = i_n - i_0 + 1
   if n ~= #new_lines then
@@ -181,7 +182,7 @@ end
 ---
 ---@param bufnr integer bufnr to get the lines from
 ---@param rows integer[] zero-indexed line numbers
----@return table<integer, string>|string a table mapping rows to lines
+---@return table<integer, string> # a table mapping rows to lines
 local function get_lines(bufnr, rows)
   --- @type integer[]
   rows = type(rows) == 'table' and rows or { rows }
@@ -219,7 +220,7 @@ local function get_lines(bufnr, rows)
   -- get the data from the file
   local fd = uv.fs_open(filename, 'r', 438)
   if not fd then
-    return ''
+    return {}
   end
   local stat = assert(uv.fs_fstat(fd))
   local data = assert(uv.fs_read(fd, stat.size, 0))
@@ -322,6 +323,8 @@ function M.apply_text_edits(text_edits, bufnr, position_encoding)
     end
   end
 
+  --- @cast text_edits  (lsp.TextEdit|{_index: integer})[]
+
   -- Sort text_edits
   ---@param a lsp.TextEdit | { _index: integer }
   ---@param b lsp.TextEdit | { _index: integer }
@@ -1298,7 +1301,6 @@ end
 ---   2. Successive empty lines are collapsed into a single empty line
 ---   3. Thematic breaks are expanded to the given width
 ---
----@private
 ---@param contents string[]
 ---@param opts? vim.lsp.util._normalize_markdown.Opts
 ---@return string[] table of lines containing normalized Markdown
@@ -1369,7 +1371,6 @@ local function close_preview_autocmd(events, winnr, bufnrs)
   end
 end
 
----@private
 --- Computes size of float needed to show contents (with optional wrapping)
 ---
 ---@param contents string[] of lines to show in window
@@ -1796,7 +1797,7 @@ function M.symbols_to_items(symbols, bufnr, position_encoding)
       'symbols_to_items must be called with valid position encoding',
       vim.log.levels.WARN
     )
-    position_encoding = vim.lsp.get_clients({ bufnr = bufnr })[1].offset_encoding
+    position_encoding = assert(vim.lsp.get_clients({ bufnr = bufnr })[1]).offset_encoding
   end
 
   local items = {} --- @type vim.quickfix.entry[]
@@ -1874,11 +1875,11 @@ end
 ---@return string filetype or "markdown" if it was unchanged.
 function M.try_trim_markdown_code_blocks(lines)
   vim.deprecate('vim.lsp.util.try_trim_markdown_code_blocks()', 'nil', '0.12')
-  local language_id = lines[1]:match('^```(.*)')
+  local language_id = assert(lines[1]):match('^```(.*)')
   if language_id then
     local has_inner_code_fence = false
     for i = 2, (#lines - 1) do
-      local line = lines[i]
+      local line = lines[i] --[[@as string]]
       if line:sub(1, 3) == '```' then
         has_inner_code_fence = true
         break
@@ -1937,7 +1938,7 @@ end
 --- Utility function for getting the encoding of the first LSP client on the given buffer.
 ---@deprecated
 ---@param bufnr integer buffer handle or 0 for current, defaults to current
----@return string encoding first client if there is one, nil otherwise
+---@return 'utf-8'|'utf-16'|'utf-32' encoding first client if there is one, nil otherwise
 function M._get_offset_encoding(bufnr)
   validate('bufnr', bufnr, 'number', true)
 
@@ -1963,6 +1964,7 @@ function M._get_offset_encoding(bufnr)
       )
     end
   end
+  --- @cast offset_encoding -? hack - not safe
 
   return offset_encoding
 end
@@ -2056,7 +2058,7 @@ end
 --- Create the workspace params
 ---@param added lsp.WorkspaceFolder[]
 ---@param removed lsp.WorkspaceFolder[]
----@return lsp.WorkspaceFoldersChangeEvent
+---@return lsp.DidChangeWorkspaceFoldersParams
 function M.make_workspace_params(added, removed)
   return { event = { added = added, removed = removed } }
 end
@@ -2105,7 +2107,7 @@ function M.character_offset(buf, row, col, offset_encoding)
       'character_offset must be called with valid offset encoding',
       vim.log.levels.WARN
     )
-    offset_encoding = vim.lsp.get_clients({ bufnr = buf })[1].offset_encoding
+    offset_encoding = assert(vim.lsp.get_clients({ bufnr = buf })[1]).offset_encoding
   end
   return vim.str_utfindex(line, offset_encoding, col, false)
 end
@@ -2168,7 +2170,6 @@ end
 ---@field method? vim.lsp.protocol.Method.ClientToServer.Request
 ---@field type? string
 
----@private
 --- Cancel all {filter}ed requests.
 ---
 ---@param filter? vim.lsp.util._cancel_requests.Filter
@@ -2203,10 +2204,9 @@ end
 ---@field client_id? integer Client ID to refresh (default: all clients)
 ---@field handler? lsp.Handler
 
----@private
 --- Request updated LSP information for a buffer.
 ---
----@param method string LSP method to call
+---@param method vim.lsp.protocol.Method.ClientToServer.Request LSP method to call
 ---@param opts? vim.lsp.util._refresh.Opts Options table
 function M._refresh(method, opts)
   opts = opts or {}
diff --git a/runtime/lua/vim/secure.lua b/runtime/lua/vim/secure.lua
index 169214871a..c3731bf595 100644
--- a/runtime/lua/vim/secure.lua
+++ b/runtime/lua/vim/secure.lua
@@ -27,8 +27,8 @@ end
 --- If {fullpath} is a directory, then nothing is read from the filesystem, and
 --- `contents = true` and `hash = "directory"` is returned instead.
 ---
----@param fullpath (string) Path to a file or directory to read.
----@param bufnr (number?) The number of the buffer.
+---@param fullpath string Path to a file or directory to read.
+---@param bufnr integer? The number of the buffer.
 ---@return string|boolean? contents the contents of the file, or true if it's a directory
 ---@return string? hash the hash of the contents, or "directory" if it's a directory
 local function compute_hash(fullpath, bufnr)
diff --git a/runtime/lua/vim/shared.lua b/runtime/lua/vim/shared.lua
index 73b7408118..9ce24719aa 100644
--- a/runtime/lua/vim/shared.lua
+++ b/runtime/lua/vim/shared.lua
@@ -105,7 +105,7 @@ end
 --- @return fun():string? : Iterator over the split components
 function vim.gsplit(s, sep, opts)
   local plain --- @type boolean?
-  local trimempty = false
+  local trimempty = false --- @type boolean?
   if type(opts) == 'boolean' then
     plain = opts -- For backwards compatibility.
   else
@@ -616,7 +616,7 @@ function vim.spairs(t)
   --- @cast t table<any,any>
 
   -- collect the keys
-  local keys = {}
+  local keys = {} --- @type string[]
   for k in pairs(t) do
     table.insert(keys, k)
   end
@@ -1027,7 +1027,7 @@ do
   ---
   --- @param name string Argument name
   --- @param value any Argument value
-  --- @param validator vim.validate.Validator
+  --- @param validator vim.validate.Validator :
   ---   - (`string|string[]`): Any value that can be returned from |lua-type()| in addition to
   ---     `'callable'`: `'boolean'`, `'callable'`, `'function'`, `'nil'`, `'number'`, `'string'`, `'table'`,
   ---     `'thread'`, `'userdata'`.
@@ -1194,7 +1194,6 @@ do
   end
 end
 
---- @private
 --- @generic T
 --- @param root string
 --- @param mod T
@@ -1214,7 +1213,6 @@ function vim._defer_require(root, mod)
   })
 end
 
---- @private
 --- Creates a module alias/shim that lazy-loads a target module.
 ---
 --- Unlike `vim.defaulttable()` this also:
@@ -1423,7 +1421,7 @@ function vim._resolve_bufnr(bufnr)
 end
 
 --- @generic T
---- @param x elem_or_list<T>?
+--- @param x T|T[]
 --- @return T[]
 function vim._ensure_list(x)
   if type(x) == 'table' then
@@ -1432,4 +1430,7 @@ function vim._ensure_list(x)
   return { x }
 end
 
+-- Use max 32-bit signed int value to avoid overflow on 32-bit systems. #31633
+vim._maxint = 2 ^ 32 - 1
+
 return vim
diff --git a/runtime/lua/vim/text.lua b/runtime/lua/vim/text.lua
index 93220a2e42..25126d738d 100644
--- a/runtime/lua/vim/text.lua
+++ b/runtime/lua/vim/text.lua
@@ -79,7 +79,7 @@ end
 ---
 --- @param size integer Number of spaces.
 --- @param text string Text to indent.
---- @param opts? { expandtab?: number }
+--- @param opts? { expandtab?: integer }
 --- @return string # Indented text.
 --- @return integer # Indent size _before_ modification.
 function M.indent(size, text, opts)
@@ -91,7 +91,7 @@ function M.indent(size, text, opts)
   local tabspaces = opts.expandtab and (' '):rep(opts.expandtab) or nil
 
   --- Minimum common indent shared by all lines.
-  local old_indent --[[@type number?]]
+  local old_indent --- @type integer?
   local prefix = tabspaces and ' ' or nil -- Indent char (space or tab).
   --- Check all non-empty lines, capturing leading whitespace (if any).
   --- @diagnostic disable-next-line: no-unknown
@@ -106,7 +106,7 @@ function M.indent(size, text, opts)
     end
     prefix = prefix and prefix or line_ws:sub(1, 1)
     local _, end_ = line_ws:find('^[' .. prefix .. ']+')
-    old_indent = math.min(old_indent or math.huge, end_ or 0)
+    old_indent = math.min(old_indent or math.huge, end_ or 0) --[[@as integer?]]
   end
   -- Default to 0 if all lines are empty.
   old_indent = old_indent or 0
diff --git a/runtime/lua/vim/treesitter.lua b/runtime/lua/vim/treesitter.lua
index c2df96d9b4..01ef856b31 100644
--- a/runtime/lua/vim/treesitter.lua
+++ b/runtime/lua/vim/treesitter.lua
@@ -280,18 +280,19 @@ function M.get_captures_at_pos(bufnr, row, col)
     end
 
     local q = buf_highlighter:get_query(tree:lang())
+    local query = q:query()
 
     -- Some injected languages may not have highlight queries.
-    if not q:query() then
+    if not query then
       return
     end
 
-    local iter = q:query():iter_captures(root, buf_highlighter.bufnr, row, row + 1)
+    local iter = query:iter_captures(root, buf_highlighter.bufnr, row, row + 1)
 
     for id, node, metadata, match in iter do
       if M.is_in_node_range(node, row, col) then
         ---@diagnostic disable-next-line: invisible
-        local capture = q._query.captures[id] -- name of the capture in the query
+        local capture = query.captures[id] -- name of the capture in the query
         if capture ~= nil then
           local _, pattern_id = match:info()
           table.insert(matches, {
diff --git a/runtime/lua/vim/treesitter/_query_linter.lua b/runtime/lua/vim/treesitter/_query_linter.lua
index 6975b7d441..8cab984598 100644
--- a/runtime/lua/vim/treesitter/_query_linter.lua
+++ b/runtime/lua/vim/treesitter/_query_linter.lua
@@ -154,7 +154,6 @@ local function lint_match(buf, match, query, lang_context, diagnostics)
   end
 end
 
---- @private
 --- @param buf integer Buffer to lint
 --- @param opts vim.treesitter.query.lint.Opts|QueryLinterNormalizedOpts|nil Options for linting
 function M.lint(buf, opts)
@@ -193,13 +192,11 @@ function M.lint(buf, opts)
   vim.diagnostic.set(namespace, buf, diagnostics)
 end
 
---- @private
 --- @param buf integer
 function M.clear(buf)
   vim.diagnostic.reset(namespace, buf)
 end
 
---- @private
 --- @param findstart 0|1
 --- @param base string
 function M.omnifunc(findstart, base)
diff --git a/runtime/lua/vim/treesitter/_range.lua b/runtime/lua/vim/treesitter/_range.lua
index 885df570c2..014f3b1c2e 100644
--- a/runtime/lua/vim/treesitter/_range.lua
+++ b/runtime/lua/vim/treesitter/_range.lua
@@ -72,7 +72,6 @@ M.cmp_pos = {
 
 setmetatable(M.cmp_pos, { __call = cmp_pos })
 
----@private
 ---Check if a variable is a valid range object
 ---@param r any
 ---@return boolean
@@ -92,7 +91,6 @@ function M.validate(r)
   return true
 end
 
----@private
 ---@param r1 Range
 ---@param r2 Range
 ---@return boolean
@@ -113,7 +111,6 @@ function M.intercepts(r1, r2)
   return true
 end
 
----@private
 ---@param r1 Range6
 ---@param r2 Range6
 ---@return Range6?
@@ -126,7 +123,6 @@ function M.intersection(r1, r2)
   return { rs[1], rs[2], rs[3], re[4], re[5], re[6] }
 end
 
----@private
 ---@param r Range
 ---@return integer, integer, integer, integer
 function M.unpack4(r)
@@ -137,14 +133,12 @@ function M.unpack4(r)
   return r[1], r[2], r[3 + off_1], r[4 + off_1]
 end
 
----@private
 ---@param r Range6
 ---@return integer, integer, integer, integer, integer, integer
 function M.unpack6(r)
   return r[1], r[2], r[3], r[4], r[5], r[6]
 end
 
----@private
 ---@param r1 Range
 ---@param r2 Range
 ---@return boolean whether r1 contains r2
@@ -188,7 +182,6 @@ local function get_offset(source, index)
   return byte
 end
 
----@private
 ---@param source integer|string
 ---@param range Range
 ---@return Range6
diff --git a/runtime/lua/vim/treesitter/dev.lua b/runtime/lua/vim/treesitter/dev.lua
index 1ce1916d4b..f44db7b668 100644
--- a/runtime/lua/vim/treesitter/dev.lua
+++ b/runtime/lua/vim/treesitter/dev.lua
@@ -15,7 +15,7 @@ local TSTreeView = {}
 ---@class (private) vim.treesitter.dev.TSTreeViewOpts
 ---@field anon boolean If true, display anonymous nodes.
 ---@field lang boolean If true, display the language alongside each node.
----@field indent number Number of spaces to indent nested lines.
+---@field indent integer Number of spaces to indent nested lines.
 
 ---@class (private) vim.treesitter.dev.Node
 ---@field node TSNode Treesitter node
@@ -290,7 +290,7 @@ end
 --- The node number is dependent on whether or not anonymous nodes are displayed.
 ---
 ---@param i integer Node number to get
----@return vim.treesitter.dev.Node
+---@return vim.treesitter.dev.Node?
 ---@package
 function TSTreeView:get(i)
   local t = self.opts.anon and self.nodes or self.named
@@ -329,8 +329,7 @@ end
 --- source buffer as its only argument and should return a string.
 --- @field title (string|fun(bufnr:integer):string|nil)
 
---- @private
----
+--- @nodoc
 --- @param opts vim.treesitter.dev.inspect_tree.Opts?
 function M.inspect_tree(opts)
   vim.validate('opts', opts, 'table', true)
@@ -401,7 +400,7 @@ function M.inspect_tree(opts)
 
       -- update source window if original was closed
       if not api.nvim_win_is_valid(win) then
-        win = vim.fn.win_findbuf(buf)[1]
+        win = assert(vim.fn.win_findbuf(buf)[1])
       end
 
       api.nvim_set_current_win(win)
@@ -475,7 +474,7 @@ function M.inspect_tree(opts)
 
       -- update source window if original was closed
       if not api.nvim_win_is_valid(win) then
-        win = vim.fn.win_findbuf(buf)[1]
+        win = assert(vim.fn.win_findbuf(buf)[1])
       end
 
       local topline, botline = vim.fn.line('w0', win), vim.fn.line('w$', win)
@@ -599,7 +598,7 @@ local function update_editor_highlights(query_win, base_win, lang)
   end
 end
 
---- @private
+--- @nodoc
 --- @param lang? string language to open the query editor for.
 --- @return boolean? `true` on success, `nil` on failure
 --- @return string? error message, if applicable
diff --git a/runtime/lua/vim/treesitter/language.lua b/runtime/lua/vim/treesitter/language.lua
index f70f99421c..5255e233fa 100644
--- a/runtime/lua/vim/treesitter/language.lua
+++ b/runtime/lua/vim/treesitter/language.lua
@@ -41,7 +41,7 @@ function M.get_lang(filetype)
     return ft_to_lang[filetype]
   end
   -- for subfiletypes like html.glimmer use only "main" filetype
-  filetype = vim.split(filetype, '.', { plain = true })[1]
+  filetype = assert(vim.split(filetype, '.', { plain = true })[1])
   return ft_to_lang[filetype] or filetype
 end
 
diff --git a/runtime/lua/vim/treesitter/languagetree.lua b/runtime/lua/vim/treesitter/languagetree.lua
index d560302f8c..c3dfb86689 100644
--- a/runtime/lua/vim/treesitter/languagetree.lua
+++ b/runtime/lua/vim/treesitter/languagetree.lua
@@ -49,7 +49,10 @@ local hrtime = vim.uv.hrtime
 local default_parse_timeout_ns = 3 * 1000000
 
 ---@type Range2
-local entire_document_range = { 0, math.huge }
+local entire_document_range = {
+  0,
+  math.huge --[[@as integer]],
+}
 
 ---@alias TSCallbackName
 ---| 'changedtree'
diff --git a/runtime/lua/vim/treesitter/query.lua b/runtime/lua/vim/treesitter/query.lua
index 8d0a185de6..b50d59e674 100644
--- a/runtime/lua/vim/treesitter/query.lua
+++ b/runtime/lua/vim/treesitter/query.lua
@@ -193,7 +193,7 @@ function M.get_files(lang, query_name, is_included)
       local langlist = modeline:match(MODELINE_FORMAT)
       if langlist then
         ---@diagnostic disable-next-line:param-type-mismatch
-        for _, incllang in ipairs(vim.split(langlist, ',', true)) do
+        for _, incllang in ipairs(vim.split(langlist, ',')) do
           local is_optional = incllang:match('%(.*%)')
 
           if is_optional then
@@ -778,7 +778,7 @@ local directive_handlers = {
 --- Adds a new predicate to be used in queries
 ---
 ---@param name string Name of the predicate, without leading #
----@param handler fun(match: table<integer,TSNode[]>, pattern: integer, source: integer|string, predicate: any[], metadata: vim.treesitter.query.TSMetadata): boolean?
+---@param handler fun(match: table<integer,TSNode[]>, pattern: integer, source: integer|string, predicate: any[], metadata: vim.treesitter.query.TSMetadata): boolean? #
 ---   - see |vim.treesitter.query.add_directive()| for argument meanings
 ---@param opts? vim.treesitter.query.add_predicate.Opts
 function M.add_predicate(name, handler, opts)
@@ -818,7 +818,7 @@ end
 --- metadata table `metadata[capture_id].key = value`
 ---
 ---@param name string Name of the directive, without leading #
----@param handler fun(match: table<integer,TSNode[]>, pattern: integer, source: integer|string, predicate: any[], metadata: vim.treesitter.query.TSMetadata)
+---@param handler fun(match: table<integer,TSNode[]>, pattern: integer, source: integer|string, predicate: any[], metadata: vim.treesitter.query.TSMetadata) #
 ---   - match: A table mapping capture IDs to a list of captured nodes
 ---   - pattern: the index of the matching pattern in the query file
 ---   - predicate: list of strings containing the full directive being called, e.g.
diff --git a/runtime/lua/vim/ui/clipboard/osc52.lua b/runtime/lua/vim/ui/clipboard/osc52.lua
index 73f64c9743..a49b690965 100644
--- a/runtime/lua/vim/ui/clipboard/osc52.lua
+++ b/runtime/lua/vim/ui/clipboard/osc52.lua
@@ -22,7 +22,7 @@ end
 function M.paste(reg)
   local clipboard = reg == '+' and 'c' or 'p'
   return function()
-    local contents = nil
+    local contents = nil --- @type string?
     local id = vim.api.nvim_create_autocmd('TermResponse', {
       callback = function(args)
         local resp = args.data.sequence ---@type string
diff --git a/src/gen/gen_eval_files.lua b/src/gen/gen_eval_files.lua
index 221c7975f6..d1bd089dd8 100755
--- a/src/gen/gen_eval_files.lua
+++ b/src/gen/gen_eval_files.lua
@@ -32,6 +32,7 @@ local LUA_API_RETURN_OVERRIDES = {
   nvim_get_command = 'table<string,vim.api.keyset.command_info>',
   nvim_get_keymap = 'vim.api.keyset.get_keymap[]',
   nvim_get_mark = 'vim.api.keyset.get_mark',
+  nvim_eval_statusline = 'vim.api.keyset.eval_statusline_ret',
 
   -- Can also return table<string,vim.api.keyset.get_hl_info>, however we need to
   -- pick one to get some benefit.
@@ -45,6 +46,7 @@ local LUA_API_RETURN_OVERRIDES = {
   nvim_get_option_info2 = 'vim.api.keyset.get_option_info',
   nvim_parse_cmd = 'vim.api.keyset.parse_cmd',
   nvim_win_get_config = 'vim.api.keyset.win_config',
+  nvim_win_text_height = 'vim.api.keyset.win_text_height_ret',
 }
 
 local LUA_API_KEYSET_OVERRIDES = {
diff --git a/src/gen/luacats_parser.lua b/src/gen/luacats_parser.lua
index 36bdc44076..cfc3c3b022 100644
--- a/src/gen/luacats_parser.lua
+++ b/src/gen/luacats_parser.lua
@@ -147,6 +147,9 @@ local function process_doc_line(line, state)
     cur_obj.fields = {}
   elseif kind == 'field' then
     --- @cast parsed nvim.luacats.Field
+    if parsed.desc == '' then
+      parsed.desc = nil
+    end
     parsed.desc = parsed.desc or state.doc_lines and table.concat(state.doc_lines, '\n') or nil
     if parsed.desc then
       parsed.desc = vim.trim(parsed.desc)
diff --git a/src/nvim/eval.lua b/src/nvim/eval.lua
index 11b9d36be9..4c0c9cb412 100644
--- a/src/nvim/eval.lua
+++ b/src/nvim/eval.lua
@@ -3970,6 +3970,7 @@ M.funcs = {
     ]=],
     name = 'getcurpos',
     params = { { 'winid', 'integer' } },
+    returns = '[integer, integer, integer, integer, integer]',
     signature = 'getcurpos([{winid}])',
   },
   getcursorcharpos = {
@@ -4313,6 +4314,7 @@ M.funcs = {
     ]=],
     name = 'getmatches',
     params = { { 'win', 'integer' } },
+    returns = 'vim.fn.getmatches.ret.item[]',
     signature = 'getmatches([{win}])',
   },
   getmousepos = {
@@ -4428,7 +4430,7 @@ M.funcs = {
     ]=],
     name = 'getpos',
     params = { { 'expr', 'string' } },
-    returns = 'integer[]',
+    returns = '[integer, integer, integer, integer]',
     signature = 'getpos({expr})',
   },
   getqflist = {
@@ -4672,7 +4674,11 @@ M.funcs = {
       <
     ]=],
     name = 'getregion',
-    params = { { 'pos1', 'table' }, { 'pos2', 'table' }, { 'opts', 'table' } },
+    params = {
+      { 'pos1', '[integer, integer, integer, integer]' },
+      { 'pos2', '[integer, integer, integer, integer]' },
+      { 'opts', '{type?:string, exclusive?:boolean}' },
+    },
     returns = 'string[]',
     signature = 'getregion({pos1}, {pos2} [, {opts}])',
   },
@@ -4712,8 +4718,12 @@ M.funcs = {
       			(default: |FALSE|)
     ]=],
     name = 'getregionpos',
-    params = { { 'pos1', 'table' }, { 'pos2', 'table' }, { 'opts', 'table' } },
-    returns = 'integer[][][]',
+    params = {
+      { 'pos1', '[integer, integer, integer, integer]' },
+      { 'pos2', '[integer, integer, integer, integer]' },
+      { 'opts', '{type?:string, exclusive?:boolean, eol?:boolean}' },
+    },
+    returns = '[ [integer, integer, integer, integer], [integer, integer, integer, integer] ][]',
     signature = 'getregionpos({pos1}, {pos2} [, {opts}])',
   },
   getregtype = {
@@ -8648,6 +8658,7 @@ M.funcs = {
     ]=],
     name = 'readfile',
     params = { { 'fname', 'string' }, { 'type', 'string' }, { 'max', 'integer' } },
+    returns = 'string[]',
     signature = 'readfile({fname} [, {type} [, {max}]])',
   },
   reduce = {
@@ -9998,7 +10009,7 @@ M.funcs = {
 
     ]=],
     name = 'setmatches',
-    params = { { 'list', 'any' }, { 'win', 'integer' } },
+    params = { { 'list', 'vim.fn.getmatches.ret.item[]' }, { 'win', 'integer' } },
     signature = 'setmatches({list} [, {win}])',
   },
   setpos = {
@@ -12924,6 +12935,7 @@ M.funcs = {
     ]=],
     name = 'virtcol',
     params = { { 'expr', 'string|any[]' }, { 'list', 'boolean' }, { 'winid', 'integer' } },
+    returns = 'integer|[integer, integer]',
     signature = 'virtcol({expr} [, {list} [, {winid}]])',
   },
   virtcol2col = {