feat(output): add toggle for maximum rendered messages

Add a workflow action and command to toggle ui.output.max_messages between a finite
number and nil (no limit). Wire the action into the API, keymaps (<leader>otm),
types, and UI so users can enable/disable the message limit from the output
notice or via command. The toggle notifies the user of the current state. Also
ensure render_output returns its promise/value so callers can await rendering when
requested.

Author: sudo-tee

lua/opencode/api.lua

@@ -89,6 +89,7 @@ local action_groups = {
     debug_session = workflow.debug_session,
     toggle_tool_output = workflow.toggle_tool_output,
     toggle_reasoning_output = workflow.toggle_reasoning_output,
+    toggle_max_messages = workflow.toggle_max_messages,
     submit_input_prompt = workflow.submit_input_prompt,
     run = workflow.run,
     run_new_session = workflow.run_new_session,

lua/opencode/commands/handlers/workflow.lua

@@ -283,6 +283,22 @@ function M.actions.toggle_reasoning_output()
   ui.render_output()
 end
 
+local original_max_messages = config.ui.output.max_messages
+function M.actions.toggle_max_messages()
+  local current = config.ui.output.max_messages
+  local next_val
+  if type(current) == 'number' and current > 0 then
+    next_val = nil
+  else
+    next_val = original_max_messages or 20
+  end
+
+  local action_text = next_val == nil and 'Disabling' or 'Enabling'
+  local val_text = next_val == nil and 'none' or tostring(next_val)
+  vim.notify(action_text .. ' message limit to ' .. val_text, vim.log.levels.INFO)
+  config.values.ui.output.max_messages = next_val
+end
+
 M.actions.review = Promise.async(function(args)
   local new_session = core.create_new_session('Code review checklist for diffs and PRs'):await()
   if not new_session then
@@ -453,6 +469,10 @@ M.command_defs = {
     desc = 'Toggle reasoning output visibility in the output window',
     execute = M.actions.toggle_reasoning_output,
   },
+  toggle_max_messages = {
+    desc = 'Toggle maximum number of rendered messages',
+    execute = M.actions.toggle_max_messages,
+  },
   paste_image = {
     desc = 'Paste image from clipboard and add to context',
     execute = M.actions.paste_image,

lua/opencode/config.lua

@@ -56,7 +56,9 @@ M.defaults = {
       ['<leader>ox'] =  { 'swap_position',                                     desc = 'Swap window position' },
       ['<leader>otr'] = { 'toggle_reasoning_output',                           desc = 'Toggle reasoning output' },
       ['<leader>ott'] = { 'toggle_tool_output',                                desc = 'Toggle tool output' },
+      ['<leader>otm'] = { 'toggle_max_messages',                               desc = 'Toggle max messages' },
       ['<leader>o/'] =  { 'quick_chat',                   mode = { 'n', 'x' }, desc = 'Quick chat with current context' },
+
     },
     output_window = {
       ['<esc>'] =       { 'close',                                             desc = 'Close Opencode windows' },

lua/opencode/types.lua

@@ -499,7 +499,7 @@
 
 ---@class OutputAction
 ---@field text string Action text
----@field type 'diff_revert_all'|'diff_revert_selected_file'|'diff_open'|'diff_restore_snapshot_file'|'diff_restore_snapshot_all'|'select_child_session' Type of action
+---@field type 'diff_revert_all'|'diff_revert_selected_file'|'diff_open'|'diff_restore_snapshot_file'|'diff_restore_snapshot_all'|'select_child_session'|'toggle_max_messages'
 ---@field args? string[] Optional arguments for the command
 ---@field key string keybinding for the action
 ---@field display_line number Line number to display the action

lua/opencode/ui/formatter.lua

@@ -106,6 +106,14 @@ function M._format_hidden_messages_notice(hidden_count)
   local message_text = hidden_count == 1 and 'message is' or 'messages are'
 
   output:add_line(string.format('> %d older %s not displayed.', hidden_count, message_text))
+  output:add_action({
+    text = 'Show [A]ll messages',
+    type = 'toggle_max_messages',
+    args = {},
+    key = 'A',
+    display_line = output:get_line_count() - 1,
+    range = { from = output:get_line_count() - 1, to = output:get_line_count() - 1 },
+  })
   output:add_empty_line()
 
   return output

lua/opencode/ui/renderer.lua

@@ -141,19 +141,31 @@ local function upsert_hidden_messages_notice(hidden_count)
 
   if not existing_message then
     ensure_message_rendered(notice_message)
-    return
+  else
+    local existing_part = ctx.render_state:get_part(HIDDEN_MESSAGES_NOTICE_PART_ID)
+    if not existing_part or not existing_part.part then
+      hide_rendered_message(HIDDEN_MESSAGES_NOTICE_MESSAGE_ID)
+      ensure_message_rendered(notice_message)
+    else
+      ctx.render_state:set_message(notice_message, existing_message.line_start, existing_message.line_end)
+      ctx.render_state:set_part(notice_message.parts[1], existing_part.line_start, existing_part.line_end)
+    end
   end
 
-  local existing_part = ctx.render_state:get_part(HIDDEN_MESSAGES_NOTICE_PART_ID)
-  if not existing_part or not existing_part.part then
-    hide_rendered_message(HIDDEN_MESSAGES_NOTICE_MESSAGE_ID)
-    ensure_message_rendered(notice_message)
-    return
+  local part_data = ctx.render_state:get_part(HIDDEN_MESSAGES_NOTICE_PART_ID)
+  if part_data then
+    ctx.render_state:add_actions(HIDDEN_MESSAGES_NOTICE_PART_ID, {
+      {
+        text = 'Toggle Max Messages',
+        type = 'toggle_max_messages',
+        args = {},
+        key = 'm',
+        range = { from = part_data.line_start, to = part_data.line_end },
+        display_line = part_data.line_start,
+      },
+    })
+    flush.mark_part_dirty(HIDDEN_MESSAGES_NOTICE_PART_ID, HIDDEN_MESSAGES_NOTICE_MESSAGE_ID)
   end
-
-  ctx.render_state:set_message(notice_message, existing_message.line_start, existing_message.line_end)
-  ctx.render_state:set_part(notice_message.parts[1], existing_part.line_start, existing_part.line_end)
-  flush.mark_part_dirty(HIDDEN_MESSAGES_NOTICE_PART_ID, HIDDEN_MESSAGES_NOTICE_MESSAGE_ID)
 end
 
 ---@param message_id string

lua/opencode/ui/ui.lua

@@ -473,12 +473,14 @@ end
 ---from opencode
 ---@param synchronous? boolean If true, waits until session is fully rendered
 ---@param opts? {force_scroll?: boolean}
+---@return Promise<OpencodeMessage[]> | OpencodeMessage[] | nil
 function M.render_output(synchronous, opts)
   local ret = renderer.render_full_session(opts)
 
   if ret and synchronous then
     ret:wait()
   end
+  return ret
 end
 
 ---@param lines string[]