Struct CancelledNotificationParams 

pub struct CancelledNotificationParams {
    pub meta: Option<NotificationMetaObject>,
    pub reason: Option<String>,
    pub request_id: RequestId,
}

Latest MCP Protocol 2026_07_28 Parameters for a notifications/cancelled notification.

JSON schema

{
 "description": "Parameters for a notifications/cancelled notification.",
 "type": "object",
 "required": [
   "requestId"
 ],
 "properties": {
   "_meta": {
     "$ref": "#/$defs/NotificationMetaObject"
   },
   "reason": {
     "description": "An optional string describing the reason for the cancellation. This MAY be logged or presented to the user.",
     "type": "string"
   },
   "requestId": {
     "description": "The ID of the request to cancel.\n\nThis MUST correspond to the ID of a request the client previously issued.",
     "$ref": "#/$defs/RequestId"
   }
 }
}

Fields

meta: Option<NotificationMetaObject>

reason: Option<String>

An optional string describing the reason for the cancellation. This MAY be logged or presented to the user.

request_id: RequestId

The ID of the request to cancel. This MUST correspond to the ID of a request the client previously issued.

Trait Implementations

impl Clone for CancelledNotificationParams

fn clone(&self) -> CancelledNotificationParams

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CancelledNotificationParams

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

Formats the value using the given formatter.

impl Default for CancelledNotificationParams

fn default() -> CancelledNotificationParams

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for CancelledNotificationParams

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for CancelledNotificationParams

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

where __S: Serializer,

Serialize this value into the given Serde serializer.