Update Task tasks.task.update
If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the MCP server so that the assistant can utilize the official REST documentation.
Scope:
taskWho can execute the method:
- any user with access to edit the task
- task Creator
The method tasks.task.update updates a task.
Method Parameters
Required parameters are marked with *
|
Name |
Description |
|
taskId* |
Task identifier. The task identifier can be obtained when creating a new task or by using the get task list method |
|
fields* |
Values of task fields. At least one field must be provided in the parameter; otherwise, the method will return an error. You can pass the
|
Code Examples
How to Use Examples in Documentation
curl -X POST \
-H "Content-Type: application/json" \
-H "Accept: application/json" \
-d '{"taskId":11,"fields":{"UF_CRM_TASK":["L_4","C_7","CO_5","D_10"],"UF_TASK_WEBDAV_FILES":["n12345","n67890"],"RESPONSIBLE_ID":123}}' \
https://**put_your_bitrix24_address**/rest/**put_your_user_id_here**/**put_your_webhook_here**/tasks.task.update
curl -X POST \
-H "Content-Type: application/json" \
-H "Accept: application/json" \
-d '{"taskId":11,"fields":{"UF_CRM_TASK":["L_4","C_7","CO_5","D_10"],"UF_TASK_WEBDAV_FILES":["n12345","n67890"],"RESPONSIBLE_ID":123},"auth":"**put_access_token_here**"}' \
https://**put_your_bitrix24_address**/rest/tasks.task.update
try
{
const response = await $b24.callMethod(
"tasks.task.update",
{
taskId: 11, // Identifier of the task you want to update
fields: {
// Example of passing multiple values in the UF_CRM_TASK field
UF_CRM_TASK: [
"L_4", // Link to lead with id 4
"C_7", // Link to contact with id 7
"CO_5", // Link to company with id 5
"D_10" // Link to deal with id 10
],
// Example of passing multiple files in the UF_TASK_WEBDAV_FILES field
UF_TASK_WEBDAV_FILES: [
"n12345", // Identifier of the first disk file
"n67890" // Identifier of the second disk file
],
RESPONSIBLE_ID: 123 // Identifier of the new Participant
}
}
);
const result = response.getData().result;
console.info("Task successfully updated");
}
catch( error )
{
console.error(error);
}
try {
$response = $b24Service
->core
->call(
'tasks.task.update',
[
'taskId' => 11, // Identifier of the task you want to update
'fields' => [
// Example of passing multiple values in the UF_CRM_TASK field
'UF_CRM_TASK' => [
'L_4', // Link to lead with id 4
'C_7', // Link to contact with id 7
'CO_5', // Link to company with id 5
'D_10' // Link to deal with id 10
],
// Example of passing multiple files in the UF_TASK_WEBDAV_FILES field
'UF_TASK_WEBDAV_FILES' => [
'n12345', // Identifier of the first disk file
'n67890' // Identifier of the second disk file
],
'RESPONSIBLE_ID' => 123 // Identifier of the new Participant
]
]
);
$result = $response
->getResponseData()
->getResult();
echo 'Task successfully updated';
} catch (Throwable $e) {
error_log($e->getMessage());
echo 'Error updating task: ' . $e->getMessage();
}
BX24.callMethod(
"tasks.task.update",
{
taskId: 11, // Identifier of the task you want to update
fields: {
// Example of passing multiple values in the UF_CRM_TASK field
UF_CRM_TASK: [
"L_4", // Link to lead with id 4
"C_7", // Link to contact with id 7
"CO_5", // Link to company with id 5
"D_10" // Link to deal with id 10
],
// Example of passing multiple files in the UF_TASK_WEBDAV_FILES field
UF_TASK_WEBDAV_FILES: [
"n12345", // Identifier of the first disk file
"n67890" // Identifier of the second disk file
],
RESPONSIBLE_ID: 123 // Identifier of the new Participant
}
},
function(result) {
if (result.error()) {
console.error(result.error());
} else {
console.info("Task successfully updated");
}
}
);
require_once('crest.php');
$result = CRest::call(
'tasks.task.update',
[
'taskId' => 11, // Identifier of the task you want to update
'fields' => [
// Example of passing multiple values in the UF_CRM_TASK field
'UF_CRM_TASK' => [
'L_4', // Link to lead with id 4
'C_7', // Link to contact with id 7
'CO_5', // Link to company with id 5
'D_10' // Link to deal with id 10
],
// Example of passing multiple files in the UF_TASK_WEBDAV_FILES field
'UF_TASK_WEBDAV_FILES' => [
'n12345', // Identifier of the first disk file
'n67890' // Identifier of the second disk file
],
'RESPONSIBLE_ID' => 123 // Identifier of the new Participant
]
]
);
if (isset($result['error'])) {
echo 'Error: ' . $result['error_description'];
} else {
echo 'Task successfully updated';
}
Response Handling
HTTP Status: 200
{
"result": {
"task": {
"id": "8157",
"title": "Task Example",
"description": "Task description with [B]formatting[/B]",
"description": "",
"mark": null,
"priority": "1",
"multitask": "N",
"notViewed": "N",
"replicate": "N",
"stageId": "0",
"sprintId": null,
"backlogId": null,
"createdBy": "503",
"createdDate": "2025-10-06T17:40:12+02:00",
"responsibleId": "503",
"changedBy": "503",
"changedDate": "2025-10-07T16:32:02+02:00",
"statusChangedBy": "503",
"closedBy": "0",
"closedDate": null,
"activityDate": "2025-10-07T16:29:55+02:00",
"dateStart": null,
"deadline": "2025-12-31T23:59:00+02:00",
"startDatePlan": "2024-11-02T11:06:00+02:00",
"endDatePlan": "2024-11-02T19:06:00+02:00",
"guid": "{1a90e51d-5423-4c1e-b1a2-664a519b4612}",
"xmlId": null,
"commentsCount": "4",
"serviceCommentsCount": "4",
"allowChangeDeadline": "N",
"allowTimeTracking": "N",
"taskControl": "N",
"addInReport": "N",
"forkedByTemplateId": null,
"timeEstimate": "0",
"timeSpentInLogs": null,
"matchWorkTime": "N",
"forumTopicId": "1439",
"forumId": "11",
"siteId": "s1",
"subordinate": "Y",
"exchangeModified": null,
"exchangeId": null,
"outlookVersion": "8",
"viewedDate": "2025-10-07T16:30:34+02:00",
"sorting": null,
"durationFact": null,
"isMuted": "N",
"isPinned": "N",
"isPinnedInGroup": "N",
"flowId": null,
"descriptionInBbcode": "Y",
"status": "2",
"statusChangedDate": "2025-10-07T16:22:24+02:00",
"durationPlan": "0",
"durationType": "days",
"favorite": "N",
"groupId": "0",
"auditors": ["503", "547"],
"accomplices": [],
"checklist": [],
"group": [],
"creator": {
"id": "503",
"name": "Maria Johnson",
"link": "/company/personal/user/503/",
"icon": "https://mysite.com/b17053/resize_cache/45749/c0120a8d7c10d63c83e32398d1ec4d9e/main/c89/c89c6b7301880958ea704b5a8470635c/4R5A1256.png",
"workPosition": "Administrator"
},
"responsible": {
"id": "503",
"name": "Maria Johnson",
"link": "/company/personal/user/503/",
"icon": "https://mysite.com/b17053/resize_cache/45749/c0120a8d7c10d63c83e32398d1ec4d9e/main/c89/c89c6b7301880958ea704b5a8470635c/4R5A1256.png",
"workPosition": "Administrator"
},
"accomplicesData": [],
"auditorsData": {
"547": {
"id": "547",
"name": "Helen",
"link": "/company/personal/user/547/",
"icon": "/bitrix/images/tasks/default_avatar.png",
"workPosition": "Lawyer"
}
},
"newCommentsCount": 0,
"action": {
"accept": false,
"decline": false,
"complete": true,
"approve": false,
"disapprove": false,
"start": true,
"pause": false,
"delegate": true,
"remove": true,
"edit": true,
"defer": true,
"renew": false,
"create": true,
"changeDeadline": true,
"checklistAddItems": true,
"addFavorite": true,
"deleteFavorite": false,
"rate": true,
"take": false,
"edit.originator": false,
"checklist.reorder": true,
"elapsedtime.add": true,
"dayplan.timer.toggle": false,
"edit.plan": true,
"checklist.add": true,
"favorite.add": true,
"favorite.delete": false
},
"checkListTree": {
"nodeId": 0,
"fields": {
"id": null,
"copiedId": null,
"entityId": null,
"userId": 503,
"createdBy": null,
"parentId": null,
"title": "",
"sortIndex": null,
"displaySortIndex": "",
"isComplete": false,
"isImportant": false,
"completedCount": 0,
"members": [],
"attachments": [],
"nodeId": null
},
"action": [],
"descendants": []
},
"checkListCanAdd": true
}
},
"time": {
"start": 1759843922,
"finish": 1759843922.725389,
"duration": 0.7253890037536621,
"processing": 0,
"date_start": "2025-10-07T16:32:02+02:00",
"date_finish": "2025-10-07T16:32:02+02:00",
"operating_reset_at": 1759844522,
"operating": 0.4929828643798828
}
}
Returned Data
|
Name |
Description |
|
result |
Object with response data |
|
task |
Object with task description after the operation is performed |
|
time |
Information about the request execution time |
Error Handling
HTTP Status: 400
{
"error": "ERROR_CORE",
"error_description": "Cannot bind the node to itself\u003Cbr\u003E"
}
|
Name |
Description |
|
error |
String error code. It may consist of digits, Latin letters, and underscores |
|
error_description |
Textual description of the error. The description is not intended to be shown to the end user in its raw form |
Possible Error Codes
|
Code |
Description |
Value |
|
|
wrong task id |
The value in the |
|
|
CTaskItem All parameters in the constructor must have real class type (internal error) |
The required parameter |
|
|
Action on the task is not allowed (internal error) |
The user does not have permission to update the task or does not have access to the task |
|
|
Could not find value for parameter {fields} (internal error) |
The |
|
|
The user specified in the "Responsible" field was not found\u003Cbr\u003E |
The |
|
|
Invalid status\u003Cbr\u003E |
An incorrect value is specified in the |
|
|
The task specified in the "Parent Task" field was not found\u003Cbr\u003E |
The |
|
|
Cannot bind the node to itself\u003Cbr\u003E |
The |
|
|
Creating cyclic links in tasks is prohibited\u003Cbr\u003E |
The |
|
|
The end date specified in the scheduling is earlier than the start date\u003Cbr\u003E |
The date and time in the |
|
|
The duration of the task specified in the scheduling is too long\u003Cbr\u003E |
The value in the |
Statuses and System Error Codes
HTTP Status: 20x, 40x, 50x
The errors described below may occur when calling any method.
|
Status |
Code |
Description |
|
|
|
An internal server error has occurred. Please contact the server administrator or Bitrix24 technical support |
|
|
|
An internal server error has occurred. Please contact the server administrator or Bitrix24 technical support |
|
|
|
The request intensity limit has been exceeded |
|
|
|
The current method is not permitted for calls using batch |
|
|
|
The maximum length of parameters passed to the batch method has been exceeded |
|
|
|
Invalid access token or webhook code |
|
|
|
The HTTPS protocol is required for method calls |
|
|
|
The REST API is blocked due to overload. This is a manual individual block; please contact Bitrix24 technical support to lift it |
|
|
|
The REST API is only available on commercial plans |
|
|
|
The user associated with the access token or webhook used to call the method lacks the necessary permissions |
|
|
|
The manifest is not available |
|
|
|
The request requires higher privileges than those provided by the webhook token |
|
|
|
The provided access token has expired |
|
|
|
The user does not have access to the application. This means that the application is installed, but the portal administrator has restricted access to this application to specific users only |
|
|
|
The public part of the site is closed. To open the public part of the site on an on-premise installation, disable the "Temporary closure of the public part of the site" option. Path to the setting: Desktop > Settings > Product Settings > Module Settings > Main Module > Temporary closure of the public part of the site |
Continue Learning
- Tasks: Overview of Methods
- Add Task tasks.task.add
- Get Task by ID tasks.task.get
- Get the list of tasks tasks.task.list
- Delete Task tasks.task.delete
- Get the list of fields tasks.task.getFields
- How to Upload a File to a Task
- How to Attach a Task to a Smart Process
- How to Create a Comment in a Task and Attach a File