feat(lsp)!: remove client-server handlers from vim.lsp.handlers

- Partition the handlers in vim.lsp.handlers as:
  - client to server response handlers (RCS)
  - server to client request handlers (RSC)
  - server to client notification handlers (NSC)

  Note use string indexes instead of protocol.methods for improved
  typing in LuaLS (tip: use hover on RCS, RSC or NSC).

12 files changed, 374 insertions, 356 deletions

diff --git a/runtime/doc/deprecated.txt b/runtime/doc/deprecated.txt
index 9c973b20bd..5e809ad26c 100644
--- a/runtime/doc/deprecated.txt
+++ b/runtime/doc/deprecated.txt
@@ -50,6 +50,12 @@ LSP
 • *vim.lsp.buf.completion*		Use |vim.lsp.completion.trigger()| instead.
 • vim.lsp.buf_request_all		The `error` key has been renamed to `err` inside
 					the result parameter of the handler.
+• *vim.lsp.with()*			Pass configuration to equivalent
+					functions in `vim.lsp.buf.*'.
+• |vim.lsp.handlers|
+	No longer support client to server response handlers. Only server to
+	client requests/notification handlers are supported.
+• *vim.lsp.handlers.signature_help()*	Use |vim.lsp.buf.signature_help()| instead.
 
 ------------------------------------------------------------------------------
 DEPRECATED IN 0.10					*deprecated-0.10*
diff --git a/runtime/doc/lsp.txt b/runtime/doc/lsp.txt
index 804eb171f7..6e5c85c019 100644
--- a/runtime/doc/lsp.txt
+++ b/runtime/doc/lsp.txt
@@ -195,41 +195,41 @@ Requests and notifications defined by the LSP specification are referred to as
 They are also listed below. Note that handlers depend on server support: they
 won't run if your server doesn't support them.
 
-- callHierarchy/incomingCalls
-- callHierarchy/outgoingCalls
-- textDocument/codeAction
-- textDocument/completion
-- textDocument/declaration*
-- textDocument/definition
-- textDocument/diagnostic
-- textDocument/documentHighlight
-- textDocument/documentSymbol
-- textDocument/formatting
-- textDocument/hover
-- textDocument/implementation*
-- textDocument/inlayHint
-- textDocument/prepareTypeHierarchy
-- textDocument/publishDiagnostics
-- textDocument/rangeFormatting
-- textDocument/rangesFormatting
-- textDocument/references
-- textDocument/rename
-- textDocument/semanticTokens/full
-- textDocument/semanticTokens/full/delta
-- textDocument/signatureHelp
-- textDocument/typeDefinition*
-- typeHierarchy/subtypes
-- typeHierarchy/supertypes
-- window/logMessage
-- window/showMessage
-- window/showDocument
-- window/showMessageRequest
-- workspace/applyEdit
-- workspace/configuration
-- workspace/executeCommand
-- workspace/inlayHint/refresh
-- workspace/symbol
-- workspace/workspaceFolders
+- `'callHierarchy/incomingCalls'`
+- `'callHierarchy/outgoingCalls'`
+- `'textDocument/codeAction'`
+- `'textDocument/completion'`
+- `'textDocument/declaration'`
+- `'textDocument/definition'`
+- `'textDocument/diagnostic'`
+- `'textDocument/documentHighlight'`
+- `'textDocument/documentSymbol'`
+- `'textDocument/formatting'`
+- `'textDocument/hover'`
+- `'textDocument/implementation'`
+- `'textDocument/inlayHint'`
+- `'textDocument/prepareTypeHierarchy'`
+- `'textDocument/publishDiagnostics'`
+- `'textDocument/rangeFormatting'`
+- `'textDocument/rangesFormatting'`
+- `'textDocument/references'`
+- `'textDocument/rename'`
+- `'textDocument/semanticTokens/full'`
+- `'textDocument/semanticTokens/full/delta'`
+- `'textDocument/signatureHelp'`
+- `'textDocument/typeDefinition*'`
+- `'typeHierarchy/subtypes'`
+- `'typeHierarchy/supertypes'`
+- `'window/logMessage'`
+- `'window/showMessage'`
+- `'window/showDocument'`
+- `'window/showMessageRequest'`
+- `'workspace/applyEdit'`
+- `'workspace/configuration'`
+- `'workspace/executeCommand'`
+- `'workspace/inlayHint/refresh'`
+- `'workspace/symbol'`
+- `'workspace/workspaceFolders'`
 
                                                                  *lsp-handler*
 LSP handlers are functions that handle |lsp-response|s to requests made by Nvim
@@ -238,7 +238,7 @@ there is no response, so they can't be handled. |lsp-notification|)
 
 Each response handler has this signature: >
 
-    function(err, result, ctx, config)
+    function(err, result, ctx)
 <
     Parameters: ~
       • {err}     (`table|nil`) Error info dict, or `nil` if the request
@@ -255,121 +255,53 @@ Each response handler has this signature: >
                                  request. Handlers can compare this to the
                                  current document version to check if the
                                  response is "stale". See also |b:changedtick|.
-      • {config}  (`table`) Handler-defined configuration table, which allows
-                  users to customize handler behavior.
-                  For an example, see:
-                      |vim.lsp.diagnostic.on_publish_diagnostics()|
-                  To configure a particular |lsp-handler|, see:
-                      |lsp-handler-configuration|
 
     Returns: ~
         Two values `result, err` where `err` is shaped like an RPC error: >
             { code, message, data? }
 <        You can use |vim.lsp.rpc.rpc_response_error()| to create this object.
 
-                                                   *lsp-handler-configuration*
-
-To configure the behavior of a builtin |lsp-handler|, the convenient method
-|vim.lsp.with()| is provided for users.
-
-  To configure the behavior of |vim.lsp.diagnostic.on_publish_diagnostics()|,
-  consider the following example, where a new |lsp-handler| is created using
-  |vim.lsp.with()| that no longer generates signs for the diagnostics: >lua
-
-    vim.lsp.handlers["textDocument/publishDiagnostics"] = vim.lsp.with(
-      vim.lsp.diagnostic.on_publish_diagnostics, {
-        -- Disable signs
-        signs = false,
-      }
-    )
-<
-  To enable signs, use |vim.lsp.with()| again to create and assign a new
-  |lsp-handler| to |vim.lsp.handlers| for the associated method: >lua
-
-    vim.lsp.handlers["textDocument/publishDiagnostics"] = vim.lsp.with(
-      vim.lsp.diagnostic.on_publish_diagnostics, {
-        -- Enable signs
-        signs = true,
-      }
-    )
-<
-  To configure a handler on a per-server basis, you can use the {handlers} key
-  for |vim.lsp.start_client()| >lua
-
-    vim.lsp.start_client {
-      ..., -- Other configuration omitted.
-      handlers = {
-        ["textDocument/publishDiagnostics"] = vim.lsp.with(
-          vim.lsp.diagnostic.on_publish_diagnostics, {
-            -- Disable virtual_text
-            virtual_text = false,
-          }
-        ),
-      },
-    }
-<
-  or if using "nvim-lspconfig", you can use the {handlers} key of `setup()`:
-  >lua
-
-    require('lspconfig').rust_analyzer.setup {
-      handlers = {
-        ["textDocument/publishDiagnostics"] = vim.lsp.with(
-          vim.lsp.diagnostic.on_publish_diagnostics, {
-            -- Disable virtual_text
-            virtual_text = false
-          }
-        ),
-      }
-    }
-<
-  Some handlers do not have an explicitly named handler function (such as
-  |vim.lsp.diagnostic.on_publish_diagnostics()|). To override these, first
-  create a reference to the existing handler: >lua
-
-    local on_references = vim.lsp.handlers["textDocument/references"]
-    vim.lsp.handlers["textDocument/references"] = vim.lsp.with(
-      on_references, {
-        -- Use location list instead of quickfix list
-        loclist = true,
-      }
-    )
-<
                                                       *lsp-handler-resolution*
-Handlers can be set by:
+Handlers can be set by (in increasing priority):
 
 - Setting a field in vim.lsp.handlers.                      *vim.lsp.handlers*
-  vim.lsp.handlers is a global table that contains the default mapping of
-  |lsp-method| names to |lsp-handlers|. To override the handler for the
-  `"textDocument/definition"` method: >lua
+  `vim.lsp.handlers` is a global table that contains the default mapping of
+  |lsp-method| names to lsp-handlers.
+
+  Example: >lua
 
-    vim.lsp.handlers["textDocument/definition"] = my_custom_default_definition
+    vim.lsp.handlers['textDocument/publishDiagnostics'] = my_custom_diagnostics_handler
 <
+  Note: this only applies for requests/notifications made by the
+  server to the client.
+
 - The {handlers} parameter of |vim.lsp.start()|. This sets the default
-  |lsp-handler| for the server being started. Example: >lua
+  |lsp-handler| for a specific server.
+
+  Example: >lua
 
     vim.lsp.start {
       ..., -- Other configuration omitted.
       handlers = {
-        ["textDocument/definition"] = my_custom_server_definition
+        ['textDocument/publishDiagnostics'] = my_custom_server_definition
       },
     }
+<
+  Note: this only applies for requests/notifications made by the
+  server to the client.
 
 - The {handler} parameter of |vim.lsp.buf_request_all()|. This sets
-  the |lsp-handler| ONLY for the given request(s). Example: >lua
+  the |lsp-handler| ONLY for the given request(s).
+
+  Example: >lua
 
     vim.lsp.buf_request_all(
       0,
-      "textDocument/definition",
+      'textDocument/publishDiagnostics',
       my_request_params,
       my_handler
     )
 <
-In summary, the |lsp-handler| will be chosen based on the current |lsp-method|
-in the following order:
-
-1. Handler passed to |vim.lsp.buf_request_all()|, if any.
-2. Handler defined in |vim.lsp.start()|, if any.
-3. Handler defined in |vim.lsp.handlers|, if any.
 
                                                             *vim.lsp.log_levels*
 Log levels are defined in |vim.log.levels|
@@ -955,14 +887,6 @@ tagfunc({pattern}, {flags})                                *vim.lsp.tagfunc()*
     Return: ~
         (`table[]`) tags A list of matching tags
 
-with({handler}, {override_config})                            *vim.lsp.with()*
-    Function to manage overriding defaults for LSP handlers.
-
-    Parameters: ~
-      • {handler}          (`lsp.Handler`) See |lsp-handler|
-      • {override_config}  (`table`) Table containing the keys to override
-                           behavior of the {handler}
-
 
 ==============================================================================
 Lua module: vim.lsp.client                                        *lsp-client*
@@ -1279,6 +1203,13 @@ Lua module: vim.lsp.buf                                              *lsp-buf*
     Fields: ~
       • {silent}?  (`boolean`)
 
+*vim.lsp.buf.signature_help.Opts*
+    Extends: |vim.lsp.util.open_floating_preview.Opts|
+
+
+    Fields: ~
+      • {silent}?  (`boolean`)
+
 
                                           *vim.lsp.buf.add_workspace_folder()*
 add_workspace_folder({workspace_folder})
@@ -1461,10 +1392,14 @@ rename({new_name}, {opts})                              *vim.lsp.buf.rename()*
                       ones where client.name matches this field.
                     • {bufnr}? (`integer`) (default: current buffer)
 
-signature_help()                                *vim.lsp.buf.signature_help()*
+signature_help({config})                        *vim.lsp.buf.signature_help()*
     Displays signature information about the symbol under the cursor in a
     floating window.
 
+    Parameters: ~
+      • {config}  (`vim.lsp.buf.signature_help.Opts?`) See
+                  |vim.lsp.buf.signature_help.Opts|.
+
 type_definition({opts})                        *vim.lsp.buf.type_definition()*
     Jumps to the definition of the type of the symbol under the cursor.
 
@@ -1514,66 +1449,24 @@ get_namespace({client_id}, {is_pull})
                      client. Defaults to push
 
                                           *vim.lsp.diagnostic.on_diagnostic()*
-on_diagnostic({_}, {result}, {ctx}, {config})
+on_diagnostic({_}, {result}, {ctx})
     |lsp-handler| for the method "textDocument/diagnostic"
 
-    See |vim.diagnostic.config()| for configuration options. Handler-specific
-    configuration can be set using |vim.lsp.with()|: >lua
-        vim.lsp.handlers["textDocument/diagnostic"] = vim.lsp.with(
-          vim.lsp.diagnostic.on_diagnostic, {
-            -- Enable underline, use default values
-            underline = true,
-            -- Enable virtual text, override spacing to 4
-            virtual_text = {
-              spacing = 4,
-            },
-            -- Use a function to dynamically turn signs off
-            -- and on, using buffer local variables
-            signs = function(namespace, bufnr)
-              return vim.b[bufnr].show_signs == true
-            end,
-            -- Disable a feature
-            update_in_insert = false,
-          }
-        )
-<
+    See |vim.diagnostic.config()| for configuration options.
 
     Parameters: ~
       • {result}  (`lsp.DocumentDiagnosticReport`)
       • {ctx}     (`lsp.HandlerContext`)
-      • {config}  (`vim.diagnostic.Opts`) Configuration table (see
-                  |vim.diagnostic.config()|).
 
                                  *vim.lsp.diagnostic.on_publish_diagnostics()*
-on_publish_diagnostics({_}, {result}, {ctx}, {config})
+on_publish_diagnostics({_}, {result}, {ctx})
     |lsp-handler| for the method "textDocument/publishDiagnostics"
 
-    See |vim.diagnostic.config()| for configuration options. Handler-specific
-    configuration can be set using |vim.lsp.with()|: >lua
-        vim.lsp.handlers["textDocument/publishDiagnostics"] = vim.lsp.with(
-          vim.lsp.diagnostic.on_publish_diagnostics, {
-            -- Enable underline, use default values
-            underline = true,
-            -- Enable virtual text, override spacing to 4
-            virtual_text = {
-              spacing = 4,
-            },
-            -- Use a function to dynamically turn signs off
-            -- and on, using buffer local variables
-            signs = function(namespace, bufnr)
-              return vim.b[bufnr].show_signs == true
-            end,
-            -- Disable a feature
-            update_in_insert = false,
-          }
-        )
-<
+    See |vim.diagnostic.config()| for configuration options.
 
     Parameters: ~
       • {result}  (`lsp.PublishDiagnosticsParams`)
       • {ctx}     (`lsp.HandlerContext`)
-      • {config}  (`vim.diagnostic.Opts?`) Configuration table (see
-                  |vim.diagnostic.config()|).
 
 
 ==============================================================================
@@ -1824,32 +1717,6 @@ stop({bufnr}, {client_id})                    *vim.lsp.semantic_tokens.stop()*
 
 
 ==============================================================================
-Lua module: vim.lsp.handlers                                    *lsp-handlers*
-
-                                           *vim.lsp.handlers.signature_help()*
-signature_help({_}, {result}, {ctx}, {config})
-    |lsp-handler| for the method "textDocument/signatureHelp".
-
-    The active parameter is highlighted with |hl-LspSignatureActiveParameter|. >lua
-        vim.lsp.handlers["textDocument/signatureHelp"] = vim.lsp.with(
-          vim.lsp.handlers.signature_help, {
-            -- Use a sharp border with `FloatBorder` highlights
-            border = "single"
-          }
-        )
-<
-
-    Parameters: ~
-      • {result}  (`lsp.SignatureHelp?`) Response from the language server
-      • {ctx}     (`lsp.HandlerContext`) Client context
-      • {config}  (`table`) Configuration table.
-                  • border: (default=nil)
-                    • Add borders to the floating window
-                    • See |vim.lsp.util.open_floating_preview()| for more
-                      options
-
-
-==============================================================================
 Lua module: vim.lsp.util                                            *lsp-util*
 
 *vim.lsp.util.open_floating_preview.Opts*
diff --git a/runtime/doc/news-0.10.txt b/runtime/doc/news-0.10.txt
index a5ded1ca22..35af570ec3 100644
--- a/runtime/doc/news-0.10.txt
+++ b/runtime/doc/news-0.10.txt
@@ -246,7 +246,7 @@ The following new features were added.
     indicator to see if a server supports a feature. Instead use
     `client.supports_method(<method>)`. It considers both the dynamic
     capabilities and static `server_capabilities`.
-  • `anchor_bias` option to |lsp-handlers| aids in positioning of floating
+  • `anchor_bias` option to lsp-handlers aids in positioning of floating
     windows.
   • |vim.lsp.util.locations_to_items()| sets the `user_data` of each item to
     the original LSP `Location` or `LocationLink`.
diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index c01bb46de7..f82cf4453e 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -87,7 +87,13 @@ LSP
   but no longer trigger the global handlers from `vim.lsp.handlers`
 • |vim.lsp.buf.typehierarchy()| now passes the correct params for each
   client request.
-
+• |vim.lsp.handlers.signature_help()| is no longer used.
+• |vim.lsp.diagnostic.on_publish_diagnostics()| and
+  |vim.lsp.diagnostic.on_diagnostic()| no longer accept a config parameter and
+  can no longer be configured with |vim.lsp.with()|.
+  Instead use: >lua
+    vim.diagnostic.config(config, vim.lsp.diagnostic.get_namespace(client_id))
+<
 
 LUA
 
diff --git a/runtime/lua/vim/lsp.lua b/runtime/lua/vim/lsp.lua
index a8ae283f64..42a0ccc3d4 100644
--- a/runtime/lua/vim/lsp.lua
+++ b/runtime/lua/vim/lsp.lua
@@ -1165,6 +1165,7 @@ function lsp.for_each_buffer_client(bufnr, fn)
   end
 end
 
+--- @deprecated
 --- Function to manage overriding defaults for LSP handlers.
 ---@param handler (lsp.Handler) See |lsp-handler|
 ---@param override_config (table) Table containing the keys to override behavior of the {handler}
diff --git a/runtime/lua/vim/lsp/_meta.lua b/runtime/lua/vim/lsp/_meta.lua
index 589a49c003..bf693ccc57 100644
--- a/runtime/lua/vim/lsp/_meta.lua
+++ b/runtime/lua/vim/lsp/_meta.lua
@@ -1,8 +1,8 @@
 ---@meta
 error('Cannot require a meta file')
 
----@alias lsp.Handler fun(err: lsp.ResponseError?, result: any, context: lsp.HandlerContext, config?: table): ...any
----@alias lsp.MultiHandler fun(results: table<integer,{err: lsp.ResponseError?, result: any}>, context: lsp.HandlerContext, config?: table): ...any
+---@alias lsp.Handler fun(err: lsp.ResponseError?, result: any, context: lsp.HandlerContext): ...any
+---@alias lsp.MultiHandler fun(results: table<integer,{err: lsp.ResponseError?, result: any}>, context: lsp.HandlerContext): ...any
 
 ---@class lsp.HandlerContext
 ---@field method string
diff --git a/runtime/lua/vim/lsp/buf.lua b/runtime/lua/vim/lsp/buf.lua
index 4818359fb3..152226a757 100644
--- a/runtime/lua/vim/lsp/buf.lua
+++ b/runtime/lua/vim/lsp/buf.lua
@@ -258,10 +258,72 @@ function M.implementation(opts)
   get_locations(ms.textDocument_implementation, opts)
 end
 
+local sig_help_ns = api.nvim_create_namespace('vim_lsp_signature_help')
+
+--- @class vim.lsp.buf.signature_help.Opts : vim.lsp.util.open_floating_preview.Opts
+--- @field silent? boolean
+
+-- TODO(lewis6991): support multiple clients
 --- Displays signature information about the symbol under the cursor in a
 --- floating window.
-function M.signature_help()
-  lsp.buf_request(0, ms.textDocument_signatureHelp, client_positional_params())
+--- @param config? vim.lsp.buf.signature_help.Opts
+function M.signature_help(config)
+  local method = ms.textDocument_signatureHelp
+
+  config = config or {}
+  config.focus_id = method
+
+  lsp.buf_request(0, method, client_positional_params(), function(err, result, ctx)
+    local client = assert(vim.lsp.get_client_by_id(ctx.client_id))
+
+    if err then
+      vim.notify(
+        client.name .. ': ' .. tostring(err.code) .. ': ' .. err.message,
+        vim.log.levels.ERROR
+      )
+      api.nvim_command('redraw')
+      return
+    end
+
+    if api.nvim_get_current_buf() ~= ctx.bufnr then
+      -- Ignore result since buffer changed. This happens for slow language servers.
+      return
+    end
+
+    -- When use `autocmd CompleteDone <silent><buffer> lua vim.lsp.buf.signature_help()` to call signatureHelp handler
+    -- If the completion item doesn't have signatures It will make noise. Change to use `print` that can use `<silent>` to ignore
+    if not result or not result.signatures or not result.signatures[1] then
+      if config.silent ~= true then
+        print('No signature help available')
+      end
+      return
+    end
+
+    local triggers =
+      vim.tbl_get(client.server_capabilities, 'signatureHelpProvider', 'triggerCharacters')
+
+    local ft = vim.bo[ctx.bufnr].filetype
+    local lines, hl = util.convert_signature_help_to_markdown_lines(result, ft, triggers)
+    if not lines or vim.tbl_isempty(lines) then
+      if config.silent ~= true then
+        print('No signature help available')
+      end
+      return
+    end
+
+    local fbuf = util.open_floating_preview(lines, 'markdown', config)
+
+    -- Highlight the active parameter.
+    if hl then
+      vim.hl.range(
+        fbuf,
+        sig_help_ns,
+        'LspSignatureActiveParameter',
+        { hl[1], hl[2] },
+        { hl[3], hl[4] }
+      )
+    end
+  end)
 end
 
 --- @deprecated
diff --git a/runtime/lua/vim/lsp/codelens.lua b/runtime/lua/vim/lsp/codelens.lua
index d8c6c27a98..fdbdda695a 100644
--- a/runtime/lua/vim/lsp/codelens.lua
+++ b/runtime/lua/vim/lsp/codelens.lua
@@ -261,7 +261,7 @@ end
 ---@param err lsp.ResponseError?
 ---@param result lsp.CodeLens[]
 ---@param ctx lsp.HandlerContext
-function M.on_codelens(err, result, ctx, _)
+function M.on_codelens(err, result, ctx)
   if err then
     active_refreshes[assert(ctx.bufnr)] = nil
     log.error('codelens', err)
diff --git a/runtime/lua/vim/lsp/diagnostic.lua b/runtime/lua/vim/lsp/diagnostic.lua
index c59e2db901..8fd30c7668 100644
--- a/runtime/lua/vim/lsp/diagnostic.lua
+++ b/runtime/lua/vim/lsp/diagnostic.lua
@@ -9,14 +9,6 @@ local augroup = api.nvim_create_augroup('vim_lsp_diagnostic', {})
 
 local DEFAULT_CLIENT_ID = -1
 
-local function get_client_id(client_id)
-  if client_id == nil then
-    client_id = DEFAULT_CLIENT_ID
-  end
-
-  return client_id
-end
-
 ---@param severity lsp.DiagnosticSeverity
 local function severity_lsp_to_vim(severity)
   if type(severity) == 'string' then
@@ -218,8 +210,7 @@ end
 --- @param client_id? integer
 --- @param diagnostics vim.Diagnostic[]
 --- @param is_pull boolean
---- @param config? vim.diagnostic.Opts
-local function handle_diagnostics(uri, client_id, diagnostics, is_pull, config)
+local function handle_diagnostics(uri, client_id, diagnostics, is_pull)
   local fname = vim.uri_to_fname(uri)
 
   if #diagnostics == 0 and vim.fn.bufexists(fname) == 0 then
@@ -231,91 +222,39 @@ local function handle_diagnostics(uri, client_id, diagnostics, is_pull, config)
     return
   end
 
-  client_id = get_client_id(client_id)
-  local namespace = M.get_namespace(client_id, is_pull)
-
-  if config then
-    --- @cast config table<string, table>
-    for _, opt in pairs(config) do
-      convert_severity(opt)
-    end
-    -- Persist configuration to ensure buffer reloads use the same
-    -- configuration. To make lsp.with configuration work (See :help
-    -- lsp-handler-configuration)
-    vim.diagnostic.config(config, namespace)
+  if client_id == nil then
+    client_id = DEFAULT_CLIENT_ID
   end
 
+  local namespace = M.get_namespace(client_id, is_pull)
+
   vim.diagnostic.set(namespace, bufnr, diagnostic_lsp_to_vim(diagnostics, bufnr, client_id))
 end
 
 --- |lsp-handler| for the method "textDocument/publishDiagnostics"
 ---
---- See |vim.diagnostic.config()| for configuration options. Handler-specific
---- configuration can be set using |vim.lsp.with()|:
----
---- ```lua
---- vim.lsp.handlers["textDocument/publishDiagnostics"] = vim.lsp.with(
----   vim.lsp.diagnostic.on_publish_diagnostics, {
----     -- Enable underline, use default values
----     underline = true,
----     -- Enable virtual text, override spacing to 4
----     virtual_text = {
----       spacing = 4,
----     },
----     -- Use a function to dynamically turn signs off
----     -- and on, using buffer local variables
----     signs = function(namespace, bufnr)
----       return vim.b[bufnr].show_signs == true
----     end,
----     -- Disable a feature
----     update_in_insert = false,
----   }
---- )
---- ```
+--- See |vim.diagnostic.config()| for configuration options.
 ---
 ---@param _ lsp.ResponseError?
 ---@param result lsp.PublishDiagnosticsParams
 ---@param ctx lsp.HandlerContext
----@param config? vim.diagnostic.Opts Configuration table (see |vim.diagnostic.config()|).
-function M.on_publish_diagnostics(_, result, ctx, config)
-  handle_diagnostics(result.uri, ctx.client_id, result.diagnostics, false, config)
+function M.on_publish_diagnostics(_, result, ctx)
+  handle_diagnostics(result.uri, ctx.client_id, result.diagnostics, false)
 end
 
 --- |lsp-handler| for the method "textDocument/diagnostic"
 ---
---- See |vim.diagnostic.config()| for configuration options. Handler-specific
---- configuration can be set using |vim.lsp.with()|:
----
---- ```lua
---- vim.lsp.handlers["textDocument/diagnostic"] = vim.lsp.with(
----   vim.lsp.diagnostic.on_diagnostic, {
----     -- Enable underline, use default values
----     underline = true,
----     -- Enable virtual text, override spacing to 4
----     virtual_text = {
----       spacing = 4,
----     },
----     -- Use a function to dynamically turn signs off
----     -- and on, using buffer local variables
----     signs = function(namespace, bufnr)
----       return vim.b[bufnr].show_signs == true
----     end,
----     -- Disable a feature
----     update_in_insert = false,
----   }
---- )
---- ```
+--- See |vim.diagnostic.config()| for configuration options.
 ---
 ---@param _ lsp.ResponseError?
 ---@param result lsp.DocumentDiagnosticReport
 ---@param ctx lsp.HandlerContext
----@param config vim.diagnostic.Opts Configuration table (see |vim.diagnostic.config()|).
-function M.on_diagnostic(_, result, ctx, config)
+function M.on_diagnostic(_, result, ctx)
   if result == nil or result.kind == 'unchanged' then
     return
   end
 
-  handle_diagnostics(ctx.params.textDocument.uri, ctx.client_id, result.items, true, config)
+  handle_diagnostics(ctx.params.textDocument.uri, ctx.client_id, result.items, true)
 end
 
 --- Clear push diagnostics and diagnostic cache.
diff --git a/runtime/lua/vim/lsp/handlers.lua b/runtime/lua/vim/lsp/handlers.lua
index ad827cfd34..2b7aefe0e1 100644
--- a/runtime/lua/vim/lsp/handlers.lua
+++ b/runtime/lua/vim/lsp/handlers.lua
@@ -5,10 +5,21 @@ local util = require('vim.lsp.util')
 local api = vim.api
 local completion = require('vim.lsp.completion')
 
---- @type table<string,lsp.Handler>
+--- @type table<string, lsp.Handler>
 local M = {}
 
--- FIXME: DOC: Expose in vimdocs
+--- @deprecated
+--- Client to server response handlers.
+--- @type table<vim.lsp.protocol.Method.ClientToServer, lsp.Handler>
+local RCS = {}
+
+--- Server to client request handlers.
+--- @type table<vim.lsp.protocol.Method.ServerToClient, lsp.Handler>
+local RSC = {}
+
+--- Server to client notification handlers.
+--- @type table<vim.lsp.protocol.Method.ServerToClient, lsp.Handler>
+local NSC = {}
 
 --- Writes to error buffer.
 ---@param ... string Will be concatenated before being written
@@ -18,14 +29,15 @@ local function err_message(...)
 end
 
 --- @see # https://microsoft.github.io/language-server-protocol/specifications/specification-current/#workspace_executeCommand
-M[ms.workspace_executeCommand] = function(_, _, _, _)
+RCS[ms.workspace_executeCommand] = function(_, _, _)
   -- Error handling is done implicitly by wrapping all handlers; see end of this file
 end
 
 --- @see # https://microsoft.github.io/language-server-protocol/specifications/specification-current/#progress
 ---@param params lsp.ProgressParams
 ---@param ctx lsp.HandlerContext
-M[ms.dollar_progress] = function(_, params, ctx)
+---@diagnostic disable-next-line:no-unknown
+RSC[ms.dollar_progress] = function(_, params, ctx)
   local client = vim.lsp.get_client_by_id(ctx.client_id)
   if not client then
     err_message('LSP[id=', tostring(ctx.client_id), '] client has shut down during progress update')
@@ -59,26 +71,26 @@ M[ms.dollar_progress] = function(_, params, ctx)
 end
 
 --- @see # https://microsoft.github.io/language-server-protocol/specifications/specification-current/#window_workDoneProgress_create
----@param result lsp.WorkDoneProgressCreateParams
+---@param params lsp.WorkDoneProgressCreateParams
 ---@param ctx lsp.HandlerContext
-M[ms.window_workDoneProgress_create] = function(_, result, ctx)
+RSC[ms.window_workDoneProgress_create] = function(_, params, ctx)
   local client = vim.lsp.get_client_by_id(ctx.client_id)
   if not client then
     err_message('LSP[id=', tostring(ctx.client_id), '] client has shut down during progress update')
     return vim.NIL
   end
-  client.progress:push(result)
+  client.progress:push(params)
   return vim.NIL
 end
 
 --- @see # https://microsoft.github.io/language-server-protocol/specifications/specification-current/#window_showMessageRequest
----@param result lsp.ShowMessageRequestParams
-M[ms.window_showMessageRequest] = function(_, result)
-  local actions = result.actions or {}
+---@param params lsp.ShowMessageRequestParams
+RSC[ms.window_showMessageRequest] = function(_, params)
+  local actions = params.actions or {}
   local co, is_main = coroutine.running()
   if co and not is_main then
     local opts = {
-      prompt = result.message .. ': ',
+      prompt = params.message .. ': ',
       format_item = function(action)
         return (action.title:gsub('\r\n', '\\r\\n')):gsub('\n', '\\n')
       end,
@@ -92,7 +104,7 @@ M[ms.window_showMessageRequest] = function(_, result)
     end)
     return coroutine.yield()
   else
-    local option_strings = { result.message, '\nRequest Actions:' }
+    local option_strings = { params.message, '\nRequest Actions:' }
     for i, action in ipairs(actions) do
       local title = action.title:gsub('\r\n', '\\r\\n')
       title = title:gsub('\n', '\\n')
@@ -108,19 +120,19 @@ M[ms.window_showMessageRequest] = function(_, result)
 end
 
 --- @see # https://microsoft.github.io/language-server-protocol/specifications/specification-current/#client_registerCapability
---- @param result lsp.RegistrationParams
-M[ms.client_registerCapability] = function(_, result, ctx)
+--- @param params lsp.RegistrationParams
+RSC[ms.client_registerCapability] = function(_, params, ctx)
   local client_id = ctx.client_id
   local client = assert(vim.lsp.get_client_by_id(client_id))
 
-  client.dynamic_capabilities:register(result.registrations)
+  client.dynamic_capabilities:register(params.registrations)
   for bufnr, _ in pairs(client.attached_buffers) do
     vim.lsp._set_defaults(client, bufnr)
   end
 
   ---@type string[]
   local unsupported = {}
-  for _, reg in ipairs(result.registrations) do
+  for _, reg in ipairs(params.registrations) do
     if reg.method == ms.workspace_didChangeWatchedFiles then
       vim.lsp._watchfiles.register(reg, ctx)
     elseif not client.dynamic_capabilities:supports_registration(reg.method) then
@@ -139,13 +151,13 @@ M[ms.client_registerCapability] = function(_, result, ctx)
 end
 
 --- @see # https://microsoft.github.io/language-server-protocol/specifications/specification-current/#client_unregisterCapability
---- @param result lsp.UnregistrationParams
-M[ms.client_unregisterCapability] = function(_, result, ctx)
+--- @param params lsp.UnregistrationParams
+RSC[ms.client_unregisterCapability] = function(_, params, ctx)
   local client_id = ctx.client_id
   local client = assert(vim.lsp.get_client_by_id(client_id))
-  client.dynamic_capabilities:unregister(result.unregisterations)
+  client.dynamic_capabilities:unregister(params.unregisterations)
 
-  for _, unreg in ipairs(result.unregisterations) do
+  for _, unreg in ipairs(params.unregisterations) do
     if unreg.method == ms.workspace_didChangeWatchedFiles then
       vim.lsp._watchfiles.unregister(unreg, ctx)
     end
@@ -153,20 +165,20 @@ M[ms.client_unregisterCapability] = function(_, result, ctx)
   return vim.NIL
 end
 
+-- TODO(lewis6991): Do we need to notify other servers?
 --- @see # https://microsoft.github.io/language-server-protocol/specifications/specification-current/#workspace_applyEdit
-M[ms.workspace_applyEdit] = function(_, workspace_edit, ctx)
+RSC[ms.workspace_applyEdit] = function(_, params, ctx)
   assert(
-    workspace_edit,
+    params,
     'workspace/applyEdit must be called with `ApplyWorkspaceEditParams`. Server is violating the specification'
   )
   -- TODO(ashkan) Do something more with label?
   local client_id = ctx.client_id
   local client = assert(vim.lsp.get_client_by_id(client_id))
-  if workspace_edit.label then
-    print('Workspace edit', workspace_edit.label)
+  if params.label then
+    print('Workspace edit', params.label)
   end
-  local status, result =
-    pcall(util.apply_workspace_edit, workspace_edit.edit, client.offset_encoding)
+  local status, result = pcall(util.apply_workspace_edit, params.edit, client.offset_encoding)
   return {
     applied = status,
     failureReason = result,
@@ -182,8 +194,8 @@ local function lookup_section(table, section)
 end