A task’s priority, client_batch_id or metadata may be updated via the API with a request to a unique URL using the projectId, taskId and access_key.

The priority field is an integer specifying the task’s new priority. Tasks with lower priority values will be worked on first, and the default is 0. Range of value is between -2147483648 and 2147483647.

The client_batch_id field is a string specifying the task’s new client_batch_id. Please inform your project manager if you update a task's client_batch_id, as it can affect reporting.

The metadata field is an object specifying the task’s new metadata. Metadata is a free-form object that can be used to store any additional information about the task. Note that the new metadata will replace the existing metadata, so if you want to update only a specific key, you need to pass the entire metadata object.

You can check current task info via the Get status of a set of tasks endpoint or the Get status of a single task endpoint.