# Checklists and to-do lists Premium users can now create collaborative checklists in any chat to track tasks and coordinate teams — or manage shopping and to-do lists. ### Checklists #### Creating checklists todoItem#cba9a52f id:int title:TextWithEntities = TodoItem; todoList#49b92a26 flags:# others_can_append:flags.0?true others_can_complete:flags.1?true title:TextWithEntities list:Vector = TodoList; inputMediaTodo#9fc55fde todo:TodoList = InputMedia; todoCompletion#221bb5e4 id:int completed_by:Peer date:int = TodoCompletion; messageMediaToDo#8a53b014 flags:# todo:TodoList completions:flags.0?Vector = MessageMedia; ---functions--- messages.sendMedia#330e77f flags:# silent:flags.5?true background:flags.6?true clear_draft:flags.7?true noforwards:flags.14?true update_stickersets_order:flags.15?true invert_media:flags.16?true allow_paid_floodskip:flags.19?true peer:InputPeer reply_to:flags.0?InputReplyTo media:InputMedia message:string random_id:long reply_markup:flags.2?ReplyMarkup entities:flags.3?Vector schedule_date:flags.10?int schedule_repeat_period:flags.24?int send_as:flags.13?InputPeer quick_reply_shortcut:flags.17?InputQuickReplyShortcut effect:flags.18?long allow_paid_stars:flags.21?long suggested_post:flags.22?SuggestedPost = Updates; Use [messages.sendMedia](/method/messages.sendMedia.md) with [inputMediaTodo](/constructor/inputMediaTodo.md) to post a to-do list: this will generate a message containing a [messageMediaToDo](/constructor/messageMediaToDo.md), containing the todo list, and detailed information about [item completions »](#mark-items-as-completed). The title of a todo list has a maximum length equal to [todo_title_length_max »](/api/config.md#todo-title-length-max). During creation, [todoList](/constructor/todoList.md).`others_can_append` can be set to allow users different from yourself to invoke [messages.appendTodoList](/method/messages.appendTodoList.md) to append items to the list. [todoList](/constructor/todoList.md).`others_can_complete` can be set to allow users different from yourself to mark items as (not) completed with [messages.toggleTodoCompleted](/method/messages.toggleTodoCompleted.md). The passed [todoItem](/constructor/todoItem.md)s are composed of a title (maximum length equal to [todo_item_length_max »](/api/config.md#todo-item-length-max)) and a positive (non-zero) ID, unique within the context of the current list. A specific task within a checklist message can be linked to using the `task` parameter of a [message deep link »](/api/links.md#message-links), which contains the [todoItem](/constructor/todoItem.md).`id` of the task to highlight. A todo list can have at most [todo_items_max »](/api/config.md#todo-items-max) items. #### Modifying checklists todoItem#cba9a52f id:int title:TextWithEntities = TodoItem; messageActionTodoAppendTasks#c7edbc83 list:Vector = MessageAction; ---functions--- messages.appendTodoList#21a61057 peer:InputPeer msg_id:int list:Vector = Updates; messages.editMessage#51e842e1 flags:# no_webpage:flags.1?true invert_media:flags.16?true peer:InputPeer id:int message:flags.11?string media:flags.14?InputMedia reply_markup:flags.2?ReplyMarkup entities:flags.3?Vector schedule_date:flags.15?int schedule_repeat_period:flags.18?int quick_reply_shortcut_id:flags.17?int = Updates; Use [messages.appendTodoList](/method/messages.appendTodoList.md) to append items to the to-do list after creation: this will emit [service messages](/constructor/messageService.md) of type [messageActionTodoAppendTasks](/constructor/messageActionTodoAppendTasks.md). The newly appended [todoItem](/constructor/todoItem.md)s must have an ID that isn't already contained within the item list, otherwise a `TODO_ITEM_DUPLICATE` RPC error will be emitted. [messages.editMessage](/method/messages.editMessage.md) can be used to remove tasks from the list, by re-specifying a modified copy of the existing [todoList](/constructor/todoList.md) as an [inputMediaTodo](/constructor/inputMediaTodo.md): removing items in this manner will not erase the completion tasks of non-deleted items, as long as their IDs aren't changed. The same method can also be used in the same manner to add multiple tasks to the list without emitting a [messageActionTodoAppendTasks](/constructor/messageActionTodoAppendTasks.md) service message. #### Mark items as completed todoCompletion#221bb5e4 id:int completed_by:Peer date:int = TodoCompletion; messageMediaToDo#8a53b014 flags:# todo:TodoList completions:flags.0?Vector = MessageMedia; messageActionTodoCompletions#cc7c5c89 completed:Vector incompleted:Vector = MessageAction; ---functions--- messages.toggleTodoCompleted#d3e03124 peer:InputPeer msg_id:int completed:Vector incompleted:Vector = Updates; Use [messages.toggleTodoCompleted](/method/messages.toggleTodoCompleted.md) to toggle some items as completed or not completed using their IDs: this will emit [service messages](/constructor/messageService.md) of type [messageActionTodoCompletions](/constructor/messageActionTodoCompletions.md), and the [todoCompletion](/constructor/todoCompletion.md) list in the message's [messageMediaToDo](/constructor/messageMediaToDo.md) will be updated accordingly. Starting from layer 217, [anonymous group admins »](/api/rights.md#anonymous-admins) that invoke [messages.toggleTodoCompleted](/method/messages.toggleTodoCompleted.md) will emit [messageActionTodoCompletions](/constructor/messageActionTodoCompletions.md) and [todoCompletion](/constructor/todoCompletion.md)s on behalf of the group itself, or the default `send_as` configured by [messages.saveDefaultSendAs](/method/messages.saveDefaultSendAs.md), see [here »](/api/channel.md#sending-messages-on-behalf-of-owned-channels-and-groups) for more info on `send_as`. #### Reply to specific items inputReplyToMessage#3bd4b7c2 flags:# reply_to_msg_id:int top_msg_id:flags.0?int reply_to_peer_id:flags.1?InputPeer quote_text:flags.2?string quote_entities:flags.3?Vector quote_offset:flags.4?int monoforum_peer_id:flags.5?InputPeer todo_item_id:flags.6?int poll_option:flags.7?bytes = InputReplyTo; messageReplyHeader#1b97dd66 flags:# reply_to_scheduled:flags.2?true forum_topic:flags.3?true quote:flags.9?true reply_to_msg_id:flags.4?int reply_to_peer_id:flags.0?Peer reply_from:flags.5?MessageFwdHeader reply_media:flags.8?MessageMedia reply_to_top_id:flags.1?int quote_text:flags.6?string quote_entities:flags.7?Vector quote_offset:flags.10?int todo_item_id:flags.11?int poll_option:flags.12?bytes = MessageReplyHeader; Clients can send messages in reply to specific items of todo lists, through the `todo_item_id` field of [inputReplyToMessage](/constructor/inputReplyToMessage.md) and [messageReplyHeader](/constructor/messageReplyHeader.md), set when replying to todo lists