Struct TaskNotificationMessage 

pub struct TaskNotificationMessage {

    pub session_id: String,
    pub task_id: String,
    pub run_id: Option<String>,
    pub status: TaskStatus,
    pub reason: Option<TaskEndReason>,
    pub summary: String,
    pub output_file: Option<String>,
    pub tool_use_id: Option<String>,
    pub usage: Option<TaskUsage>,
    pub resource_links: Vec<ResourceLink>,
    pub handback: Option<TaskHandback>,
    pub handback_report: Option<HandbackReport>,
    pub skip_transcript: Option<bool>,
    pub ambient: Option<bool>,
    pub uuid: Option<String>,
}

task_notification system message — emitted once when a background task completes or fails.

Fields

session_id: String

task_id: String

run_id: Option<String>

Id of the task run this notification closes; see TaskStartedMessage::run_id (CLI 2.1.292+).

status: TaskStatus

reason: Option<TaskEndReason>

Machine-readable cause, set only when the task did not end through an ordinary completion, failure, or stop (CLI 2.1.273+).

summary: String

output_file: Option<String>

tool_use_id: Option<String>

usage: Option<TaskUsage>

resource_links: Vec<ResourceLink>

For a backgrounded MCP task that completed, the resource_link content blocks of its final result — the files it returned by reference — collected from the raw result before the CLI renders it as text. Join to the originating call via tool_use_id. Absent when the result had none or the task is any other type (CLI 2.1.259+).

handback: Option<TaskHandback>

On a completed notification of a subagent that reports through the SubagentHandback tool: how its report reached its caller. Left out when the subagent failed, was stopped, or is still waiting on work; summary is then not a report. When present, summary holds harness notes written for the model. A later notification for the same task_id replaces what an earlier one showed (CLI 2.1.292+).

handback_report: Option<HandbackReport>

The report a send or flagged hand-back delivered: when present, render it instead of summary, with its warning, if any, above its text. Absent for withheld (CLI 2.1.292+).

skip_transcript: Option<bool>

ambient: Option<bool>

True for housekeeping tasks the CLI does not surface as user work; hosts should exclude them from activity indicators (CLI 2.1.259+).

uuid: Option<String>

Trait Implementations

impl Clone for TaskNotificationMessage

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TaskNotificationMessage

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for TaskNotificationMessage

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for TaskNotificationMessage

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.