task_update MCP tool

Updates an existing task in an agent’s checklist. Can change the task’s status, subject, description, or add dependency edges between tasks. Equivalent to murmur task update in the CLI.

Parameters

Name	Type	Required	Description
`task_id`	string	yes	ID of the task to update.
`status`	string	no	New task status: `pending`, `in_progress`, `completed`, or `deleted`.
`subject`	string	no	New task subject.
`description`	string	no	New task description.
`add_blocks`	string[]	no	Task IDs that this task blocks. Adds forward dependency edges.
`add_blocked_by`	string[]	no	Task IDs that block this task. Adds reverse dependency edges.
`slug`	string	no	Agent slug. Empty means self. Use an absolute path like `/w/{workspace}/{owner_provider}/{account}/{slug}` (e.g. `/w/backend/github_oauth/alice/fix-auth`) to target an agent outside your own path.
`workspace`	string	no	Workspace name. Overrides the session default. Required only when nothing else supplies one: off a VM, with no session default, and with a slug that is not a `/w/{workspace}/...` path.

Dependency edges

Tasks can declare dependencies on other tasks using add_blocks and add_blocked_by. These edges express ordering constraints:

add_blocks: “this task blocks those tasks” — the listed tasks cannot start until this one completes.
add_blocked_by: “this task is blocked by those tasks” — this task cannot start until the listed tasks complete.

Both directions create the same underlying edge. Use whichever reads more naturally for your use case.

Response

Returns a confirmation string: updated task <task_id>.

Examples

Mark a task completed

{
  "task_id": "t_abc123",
  "status": "completed"
}

Response:

updated task t_abc123

Update subject and description

{
  "task_id": "t_abc123",
  "subject": "Add pagination to the users API (v2)",
  "description": "Use cursor-based pagination instead of offset."
}

Add dependency edges

{
  "task_id": "t_deploy",
  "add_blocked_by": ["t_tests", "t_review"]
}

This means t_deploy cannot start until both t_tests and t_review are completed.

Delete a task

{
  "task_id": "t_abc123",
  "status": "deleted"
}

Errors

Code	Meaning	What to do
`INVALID_ARGUMENT`	Unknown status value or invalid task ID.	Check the error message. Valid statuses: `pending`, `in_progress`, `completed`, `deleted`.
`NOT_FOUND`	Task or agent not found.	Check the `task_id` and `slug`. Use `task_list` to see existing tasks.
`UNAUTHENTICATED`	Identity token is missing or expired.	Check credentials.

murmur task update — equivalent CLI command
task_create — create a new task
task_list — list all tasks
task_get — get a single task

Getting Started

Core Concepts

Guides

task_update MCP tool

Parameters

Dependency edges

Response

Examples

Mark a task completed

Update subject and description

Add dependency edges

Delete a task

Errors

​Parameters

​Dependency edges

​Response

​Examples

​Mark a task completed

​Update subject and description

​Add dependency edges

​Delete a task

​Errors

​Related

Parameters

Dependency edges

Response

Examples

Mark a task completed

Update subject and description

Add dependency edges

Delete a task

Errors

Related