Work with task collaborators

All plansProject Member

A task in Onplana has one assignee, the person accountable for getting it done. Real work is often shared, though: a designer and a developer on the same screen, a reviewer who signs it off, a specialist pulled in for a day. Collaborators are those people. The task stays one person’s responsibility, and everyone working on it can find it, hear about it and update it.

A task can have up to 20 collaborators, on every plan.

What a collaborator can and cannot do

A collaborator can	Collaborating does not let them
See the task in My Work, marked Collaborating	Reassign the task to someone else
Edit it as the assignee would: status, progress, dates, description and the other fields	Add or remove other collaborators
Comment on it	Move it to another project
Attach files, and delete the files they attached	Delete it
Get notified when they are added, and about new comments
Leave the task whenever they like

Two things qualify that table.

Collaborating works inside a person’s project role. It does not add to it. With the default roles, Project Contributors and up can edit the tasks they work on and comment on them. A Project Viewer who collaborates sees the task and hears about it, but cannot change it.
The right-hand column is what collaborating does not grant. Someone whose project role already allows those actions, such as a Project Manager, can still take them, exactly as before.

Collaborators carry no workload. Capacity, workload, cost and resource leveling count the assignee only, and a task with collaborators but no assignee still counts as unassigned.

Who can add and remove collaborators

You can add or remove collaborators on a task when your project role lets you assign tasks, and you can either edit any task in the project or you are the task’s assignee. With the default roles that means:

the project’s Owner and its Project Managers, on any task;
a Project Member, on a task assigned to them.

Organization Owners and Admins act as Project Owner on every project, and Portfolio Managers act as Project Manager. Project Contributors and Viewers cannot add collaborators. Your admin can change these defaults in the permission matrix.

Anyone can remove themselves from a task, whatever their role.

A collaborator must be a member of the task’s project and active in your workspace. The picker lists the project’s members, apart from the assignee. When the person you want is not on the project yet, Someone missing? at the foot of the picker either invites them or, if you cannot invite people, asks the project’s managers to add them.

Add collaborators on the web

Open the task from any view.
In the panel on the right, find Collaborators, directly under Assignee.
Select Add collaborators and pick one or more people. Each change saves straight away; there is nothing else to confirm.

To take someone off, open the picker and clear them. When Onplana cannot add someone, a message says why: they are not on the project, they already hold the task, or the task has reached 20 collaborators.

You can also name collaborators while creating a task. Open More options and use Collaborators, which appears when you are allowed to add them to the task you are creating. They are added the moment the task exists.

Where collaborators show up

List, Board, Sprint, Backlog and Gantt show a small +N beside the assignee. Point at it to see who they are.
Grid has a Collaborators column, hidden until you turn it on from Columns. It is read-only there; change collaborators on the task itself.
My Work lists the tasks you collaborate on alongside the ones assigned to you. Each carries a Collaborating chip naming who holds the task, and the Role filter narrows the list to Assigned to me or Collaborating.
Mine, the toggle on the List view, shows the tasks assigned to you or that you collaborate on.
The task’s History records who added or removed collaborators, and so does the project’s activity feed.

Stop collaborating

When you no longer need to follow a task, open it and select Stop collaborating under Collaborators. It is always there for your own place on a task, whatever your role. If you can manage the task’s collaborators, clear yourself in the picker instead.

Notifications

Added to a task. You get a notification, and an email too if you receive email for Task assigned to me in your notification preferences. Being removed sends nothing.
Comments. A new comment on the task reaches its collaborators along with the assignee. Nobody is told about their own comment.
Schedule updates. When someone opens the project in Onplana Schedule and sends back changes that move the task’s dates or remove it, the collaborators are told along with the assignee.
Workflows (Pro plan and up) can include collaborators: Send in-app notification has Also notify the task’s collaborators, and Send email accepts Task collaborators as a recipient.

Calendar sync and Microsoft To Do stay with the assignee. A task you only collaborate on does not appear in your calendar or your To Do list.

From ChatGPT or Claude

With Onplana connected in ChatGPT or Claude, ask in plain words:

Add Priya and Sam as collaborators on the "Checkout redesign" task.

The agent uses the update_task_collaborators tool, which adds and removes people in one call. People are named the way an assignee is: by full or first name, email address or user ID. A name that matches nobody in your workspace, or matches more than one person, is left out and comes back as a warning rather than as a guess. Anyone Onplana does not add, for example because they are not on the project, comes back with the reason.

The agent is held to the same rules as the web app. If it says it is not allowed to change a task’s collaborators, check your role on that project.

You can name collaborators while creating work, too:

create_task and bulk_create_tasks take a list of collaborators for each task. The people must already be on the project.
instantiate_plan, which builds a whole plan in one call, first adds a named collaborator to the project when they are an active member of your workspace, the same way it does for assignees.

Reading works the same way. get_task and list_tasks return each task’s collaborators, and list_my_tasks returns the tasks you hold or collaborate on, with your role on each.

An AI agent can be a collaborator as well, if it is on the project. Adding it does not hand it the task: to have an agent do the work, assign the task to it. See Create a project from ChatGPT or Claude for planning work this way.

Imported plans

When a file names more than one person on a task, one becomes the assignee and the others become collaborators.

Microsoft Project files (.mpp and Project XML): the first resource on a task becomes its assignee. A resource assigned at 0% units, meaning someone on the task with no work of their own, is passed over for that. When every resource on a task is at 0%, the task gets no assignee, and the import’s warnings say how many tasks that happened to. Every resource that is not the assignee and whose email address belongs to an active member of your workspace becomes a collaborator. If they are not on the project yet, they are added to it first as a Project Contributor. A resource who is not in your workspace yet is kept with the task and becomes a collaborator when they accept an invitation to join. A resource the file names without an email address cannot be matched automatically; type an address for it on the wizard’s Resources step and it is matched like the rest.
Microsoft Planner and Project for the web: assignees after the first become collaborators when they match someone in your workspace. The import summary counts any it could not match.

An import never notifies the people it adds as collaborators. See Import a Microsoft Project file.

Coming to the Onplana Tasks apps

The browser extension, the Windows and Mac apps, and the iPhone and Android apps gain collaborators with their next releases. Until then, manage collaborators on the web or through ChatGPT or Claude.

The Excel and Microsoft Project XML exports carry the assignee only.

FAQs

Can a task have more than one assignee? No. A task has one assignee, who is accountable for it, and up to 20 collaborators who work on it with them.

Why can I not add someone? They may not be a member of the task’s project, they may already be its assignee, or the task may have 20 collaborators. If the picker is greyed out, your project role does not let you change this task’s collaborators; you can still remove yourself.

What happens if I make a collaborator the assignee? They stop being a collaborator. The assignee is never also listed as a collaborator.

What happens when a collaborator leaves the project? They stop collaborating on its tasks. The same happens when someone leaves your workspace.

Do collaborators count toward capacity or workload? No. Capacity, workload, cost and resource leveling count the assignee only.

What happens to collaborators when a task is copied, moved or repeated? A copy into another project keeps the collaborators who are members there. A task moved to another project keeps only the collaborators who are members of the new project. The next occurrence of a recurring task keeps its collaborators.

If I delete a task and restore it, are the collaborators back? Yes, the ones who are still on the project. See Restore from the recycle bin.

Work with tasks, the fields on a task and who can edit it
Work from My Work, where your tasks and collaborations come together
Understand roles and permissions, the project roles behind these rules
Import a Microsoft Project file, how resources become assignees and collaborators

Was this helpful?