kill MCP tool - Murmur

Cancels an agent task and its entire subtree of child agents. The agent’s VM is terminated and all in-progress work stops. Equivalent to murmur kill in the CLI.

This is a destructive operation. The agent and all its children are permanently cancelled. Use interrupt if you only want to stop the current turn.

Parameters

Name	Type	Required	Description
`slug`	string	yes	Agent task slug to kill. 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.

Response

Returns a confirmation string: killed <slug>.

Examples

Kill an agent

{
  "slug": "fix-auth"
}

Response:

killed fix-auth

Kill using absolute path

{
  "slug": "/w/backend/github_oauth/bob/api-refactor"
}

Errors

Code	Meaning	What to do
`NOT_FOUND`	No agent with that slug exists.	Check the slug. Use `ls` to see running agents.
`UNAUTHENTICATED`	Identity token is missing or expired.	Check credentials.

murmur kill — equivalent CLI command
interrupt — stop the current turn without killing the agent
ls — list running agents
status — check agent state
spawn — create an agent