---
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markdown_url: "https://docs.composio.dev/toolkits/microsoft_todo.md"
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---

# Microsoft To Do

Microsoft To Do is a cloud-based task management application that lets users create, organize, and track task lists, tasks, checklist items, and reminders across devices via Microsoft Graph

- **Category:** task management
- **Auth:** OAUTH2
- **Composio-managed OAuth available?** No
- **Tools:** 25
- **Triggers:** 0
- **Slug:** `MICROSOFT_TODO`
- **Version:** 20261014_00

## Tools

### Complete Task

**Slug:** `MICROSOFT_TODO_COMPLETE_TASK`

Mark a Microsoft To Do task as completed. Convenience wrapper that always PATCHes status='completed'; the server auto-sets completedDateTime. Use Update Task to reopen a task (status='notStarted') or to change other fields.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list that contains the task. |
| `task_id` | string | Yes | Id of the task to mark as completed. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Create Checklist Item

**Slug:** `MICROSOFT_TODO_CREATE_CHECKLIST_ITEM`

Add a checklist item (subtask) to a Microsoft To Do task. Only display_name is required; the created item is returned with a GUID id, displayName, isChecked, and createdDateTime.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list containing the task (path param todoTaskListId). |
| `task_id` | string | Yes | Id of the task to add the subtask to (path param taskId). |
| `is_checked` | boolean | No | Whether the item starts checked (completed). Defaults server-side to false. |
| `display_name` | string | Yes | Text of the checklist item / subtask. Required — maps to the 'displayName' body field. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Create Linked Resource

**Slug:** `MICROSOFT_TODO_CREATE_LINKED_RESOURCE`

Attach a partner-application link to an existing Microsoft To Do task.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task to attach the linked resource to. |
| `web_url` | string | Yes | Deep link to the item in the source application. |
| `external_id` | string | Yes | Id of the item in the source application. |
| `display_name` | string | Yes | Title of the linked item. |
| `application_name` | string | Yes | Name of the source application. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Create Task

**Slug:** `MICROSOFT_TODO_CREATE_TASK`

Create a task in a Microsoft To Do task list. Only title is required. Dates are passed as flat ISO-8601 strings plus a shared timezone; the tool builds the Graph dateTimeTimeZone objects. Notes are passed as body_content (+ body_content_type). NOTE: To Do treats due dates as whole days — the time component of due_date_time is normalized to midnight on save.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `title` | string | Yes | Task title. Required — omitting it returns HTTP 400 'The property title is required'. |
| `status` | string ("notStarted" | "inProgress" | "completed" | "waitingOnOthers" | "deferred") | No | Task status: 'notStarted', 'inProgress', 'completed', 'waitingOnOthers', or 'deferred'. Defaults server-side to 'notStarted'. |
| `list_id` | string | Yes | Id of the task list to create the task in (path param todoTaskListId). |
| `time_zone` | string | No | IANA/Windows timezone name applied to due_date_time, start_date_time, and reminder_date_time (e.g. 'UTC', 'Pacific Standard Time'). Graph may normalize the returned dateTimeTimeZone to UTC rather than preserve this name. |
| `categories` | array | No | List of category name strings to tag the task with. |
| `importance` | string ("low" | "normal" | "high") | No | Task importance: 'low', 'normal', or 'high'. Defaults server-side to 'normal'. |
| `body_content` | string | No | Free-text notes/description for the task (maps to body.content). |
| `due_date_time` | string | No | Due date as an ISO-8601 local datetime, e.g. '2026-07-10T00:00:00'. Combined with time_zone into the Graph dueDateTime object. NOTE: To Do treats due dates as whole days — the time component is normalized to midnight on save (e.g. 17:00 becomes 00:00). |
| `is_reminder_on` | boolean | No | Whether a reminder is active. A provided reminder_date_time always activates it. |
| `start_date_time` | string | No | Start date as an ISO-8601 local datetime; combined with time_zone into the Graph startDateTime object. |
| `body_content_type` | string ("text" | "html") | No | Content type of body_content: 'text' or 'html' (maps to body.contentType). Only used when body_content is set. Microsoft To Do may normalize stored HTML to plain text and strip markup. |
| `reminder_date_time` | string | No | Reminder date/time as an ISO-8601 local datetime; combined with time_zone into the Graph reminderDateTime object. Providing this always activates the reminder. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Create Task List

**Slug:** `MICROSOFT_TODO_CREATE_TASK_LIST`

Create a new Microsoft To Do task list.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `display_name` | string | Yes | Name of the new task list. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Delete Checklist Item

**Slug:** `MICROSOFT_TODO_DELETE_CHECKLIST_ITEM`

Delete a checklist item (subtask) from a Microsoft To Do task. This permanently removes the checklist item (this cannot be undone).

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list that contains the task. |
| `task_id` | string | Yes | Id of the task that contains the checklist item. |
| `checklist_item_id` | string | Yes | Id (GUID) of the checklist item (subtask) to delete. This cannot be undone. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Delete Task

**Slug:** `MICROSOFT_TODO_DELETE_TASK`

Delete a task from a Microsoft To Do task list. WARNING: this also permanently removes the task's checklist items and linked resources.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list that contains the task to delete. |
| `task_id` | string | Yes | Id of the task to delete. Deleting a task permanently removes its checklist items and linked resources (this cannot be undone). |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Delete Task Attachment

**Slug:** `MICROSOFT_TODO_DELETE_TASK_ATTACHMENT`

Permanently delete a file attachment from a Microsoft To Do task. This cannot be undone.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task containing the attachment. |
| `attachment_id` | string | Yes | Id of the file attachment to permanently delete. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Delete Task List

**Slug:** `MICROSOFT_TODO_DELETE_TASK_LIST`

Delete a Microsoft To Do task list. WARNING: this cascades — all tasks in the list and their checklist items are permanently deleted.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list to delete. Deleting a list permanently removes all of its tasks and their checklist items (this cascade cannot be undone). |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Download Task Attachment

**Slug:** `MICROSOFT_TODO_DOWNLOAD_TASK_ATTACHMENT`

Download one file attached to a Microsoft To Do task. The file is offloaded to storage and returned as a downloadable reference rather than inline base64.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task containing the attachment. |
| `attachment_id` | string | Yes | Id of the file attachment to download. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Get Checklist Item

**Slug:** `MICROSOFT_TODO_GET_CHECKLIST_ITEM`

Get a single Microsoft To Do checklist item (subtask) by its id, within a task in a task list.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the To Do task list that contains the task (path param todoTaskListId). This is the long URL-safe id returned by the list/create task-list actions, not the display name. |
| `task_id` | string | Yes | Id of the task that owns the checklist item (path param taskId). This is the long URL-safe id returned by the list/create task actions. |
| `checklist_item_id` | string | Yes | Id (GUID) of the checklist item to fetch (path param checklistItemId). This is the GUID returned by the list/create checklist-item actions. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Get Current User

**Slug:** `MICROSOFT_TODO_GET_CURRENT_USER`

Return the profile of the Microsoft account connected to this toolkit (whoami / connection verification). Useful to confirm which mailbox the To Do tasks belong to before other operations.

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Get Task

**Slug:** `MICROSOFT_TODO_GET_TASK`

Get a single Microsoft To Do task by its id, within a task list. Set include_checklist_items=true to expand its checklist items inline.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `expand` | string | No | Advanced OData $expand expression. Normally leave unset and use include_checklist_items instead. |
| `list_id` | string | Yes | Id of the To Do task list that contains the task (path param todoTaskListId). This is the long URL-safe id returned by the list/create task-list actions, not the display name. |
| `task_id` | string | Yes | Id of the task to fetch (path param taskId). This is the long URL-safe id returned by the list/create task actions. |
| `include_checklist_items` | boolean | No | When true, request the task's checklist items (subtasks) inline. When false, the tool does not send a $expand query. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Get Task Attachment

**Slug:** `MICROSOFT_TODO_GET_TASK_ATTACHMENT`

Get metadata for one file attached to a Microsoft To Do task. Use Download Task Attachment to retrieve the file contents.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task containing the attachment. |
| `attachment_id` | string | Yes | Id of the file attachment to retrieve. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Get Task List

**Slug:** `MICROSOFT_TODO_GET_TASK_LIST`

Get a single Microsoft To Do task list by its id.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the To Do task list to fetch. This is the long URL-safe id returned by the list/create task-list actions (e.g. the `id` field), not the display name. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### List Checklist Items

**Slug:** `MICROSOFT_TODO_LIST_CHECKLIST_ITEMS`

List the checklist items (subtasks) of a To Do task. Auto-paginates so all subtasks are returned at once as {items: [...]}.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list that owns the task (path param todoTaskListId). Get one from MICROSOFT_TODO_LIST_TASK_LISTS. |
| `task_id` | string | Yes | Id of the task whose checklist items (subtasks) to return (path param taskId). Get one from MICROSOFT_TODO_LIST_TASKS. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### List Linked Resources

**Slug:** `MICROSOFT_TODO_LIST_LINKED_RESOURCES`

List external resources linked to a Microsoft To Do task. Auto-paginates the task's small linked-resource collection and returns all items at once.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task whose linked resources to list. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### List Task Attachments

**Slug:** `MICROSOFT_TODO_LIST_TASK_ATTACHMENTS`

List the files attached to a Microsoft To Do task. Returns attachment metadata without file contents, one page at a time, plus a next_cursor.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `cursor` | string | No | Pagination token from a previous call's next_cursor. Omit for the first page; pass it back unchanged to fetch the next page. |
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task whose file attachments to list. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### List Task Lists

**Slug:** `MICROSOFT_TODO_LIST_TASK_LISTS`

List the To Do task lists owned by the connected user. The built-in default list has wellknown_list_name='defaultList'; user-created lists have wellknown_list_name='none'. Always returns at least the default list. Select the default list by id or wellknown_list_name, never by the localized display_name.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `top` | integer | No | Max task lists to return per page (maps to OData $top). The server may cap this. If omitted the server uses its default page size. |
| `cursor` | string | No | Pagination token from a previous call's next_cursor. Omit for the first page; pass it back to fetch the next page. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### List Tasks

**Slug:** `MICROSOFT_TODO_LIST_TASKS`

List the tasks in a To Do task list. Checklist items (subtasks) are NOT returned by default; set include_checklist_items=true to expand them inline. Returns one page of tasks plus a next_cursor for the next page.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `top` | integer | No | Max tasks to return per page (maps to OData $top). The server may cap this. If omitted the server uses its default page size. |
| `cursor` | string | No | Pagination token from a previous call's next_cursor. Omit for the first page; pass it back to fetch the next page. |
| `expand` | string | No | Advanced OData $expand expression. Normally leave unset and use include_checklist_items instead; that derives $expand=checklistItems. |
| `filter` | string | No | Optional OData $filter expression, e.g. "status eq 'notStarted'" or "importance eq 'high'". Advanced; omit to return all tasks. |
| `list_id` | string | Yes | Id of the task list whose tasks to return (path param todoTaskListId). Get one from MICROSOFT_TODO_LIST_TASK_LISTS. |
| `include_checklist_items` | boolean | No | When true, expand each task's checklist items (subtasks) inline (maps to OData $expand=checklistItems). Default false. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Sync Task Lists

**Slug:** `MICROSOFT_TODO_SYNC_TASK_LISTS`

Read one page of Microsoft To Do task-list changes. Continue the current round with next_cursor, or store the terminal delta_token to retrieve only changes from a later round. Removed task lists retain their removal marker.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `cursor` | string | No | Opaque continuation cursor returned by the previous page in the current synchronization round. Pass it back unchanged. |
| `select` | string | No | Comma-separated OData fields to select on the initial request. This selection is retained by continuation cursors. |
| `delta_token` | string | No | Checkpoint returned after an earlier synchronization round completed. Omit when starting the first round. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Update Checklist Item

**Slug:** `MICROSOFT_TODO_UPDATE_CHECKLIST_ITEM`

Update a checklist item (subtask) of a Microsoft To Do task: rename it (display_name) and/or check/uncheck it (is_checked). Partial update: only the fields you pass are changed; at least one is required. Setting is_checked=true marks the subtask done.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task that owns the checklist item. |
| `is_checked` | boolean | No | Set true to check off the subtask (mark it done), false to uncheck it. Checking auto-populates checkedDateTime server-side. |
| `display_name` | string | No | New text for the checklist item (maps to displayName). Replaces the existing text when provided. |
| `checklist_item_id` | string | Yes | Id (GUID) of the checklist item (subtask) to update. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Update Task

**Slug:** `MICROSOFT_TODO_UPDATE_TASK`

Update fields of an existing Microsoft To Do task (title, notes, importance, status, due/start/reminder dates, categories). Partial update: only the fields you pass are changed; unset fields are left untouched. To mark a task done set status='completed' (or use the dedicated Complete Task tool).

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `title` | string | No | New task title. |
| `status` | string ("notStarted" | "inProgress" | "completed" | "waitingOnOthers" | "deferred") | No | Task status: 'notStarted', 'inProgress', 'completed', 'waitingOnOthers', or 'deferred'. Setting 'completed' auto-populates completedDateTime server-side. |
| `list_id` | string | Yes | Id of the task list containing the task to update. |
| `task_id` | string | Yes | Id of the task to update. |
| `time_zone` | string | No | IANA/Windows timezone name applied to any of the date fields provided (due_date_time, start_date_time, reminder_date_time). Defaults to 'UTC'. Graph may normalize returned dateTimeTimeZone values to UTC rather than preserve this name. |
| `categories` | array | No | Replacement list of category name strings to tag the task with. |
| `importance` | string ("low" | "normal" | "high") | No | Task importance: 'low', 'normal', or 'high'. |
| `body_content` | string | No | New notes/description for the task (maps to body.content). Replaces the existing notes when provided. |
| `due_date_time` | string | No | New due date as an ISO-8601 local datetime (e.g. '2026-07-10T00:00:00'). Combined with time_zone into the Graph dueDateTime object. Note: To Do treats due dates as whole days, so the time component is normalized to midnight on save. Pass null to clear it. |
| `is_reminder_on` | boolean | No | Whether a reminder is active. A provided reminder_date_time always activates it. |
| `start_date_time` | string | No | New start date as an ISO-8601 local datetime; combined with time_zone into the startDateTime object. Pass null to clear it. |
| `body_content_type` | string ("text" | "html") | No | Content type of body_content: 'text' or 'html' (maps to body.contentType). Only used when body_content is provided; defaults to 'text'. Microsoft To Do may normalize stored HTML to plain text and strip markup. |
| `reminder_date_time` | string | No | New reminder date/time as an ISO-8601 local datetime; combined with time_zone into the reminderDateTime object. Providing this always activates the reminder. Pass null to clear it. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Update Task List

**Slug:** `MICROSOFT_TODO_UPDATE_TASK_LIST`

Rename a Microsoft To Do task list (updates its displayName).

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `list_id` | string | Yes | Id of the task list to update. |
| `display_name` | string | Yes | New name for the task list. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |

### Upload Task Attachment

**Slug:** `MICROSOFT_TODO_UPLOAD_TASK_ATTACHMENT`

Attach a file up to 25 MB to a Microsoft To Do task. The tool automatically uses a single request for files under 3 MB and a chunked upload session for larger files.

#### Input Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `file` | object | Yes | File to attach. Files under 3 MB use a single request; larger files up to 25 MB use a chunked upload session automatically. |
| `list_id` | string | Yes | Id of the task list containing the task. |
| `task_id` | string | Yes | Id of the task that should receive the file attachment. |

#### Output

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `data` | string | Yes | Data from the action execution |
| `error` | string | No | Error if any occurred during the execution of the action |
| `successful` | boolean | Yes | Whether or not the action execution was successful or not |