Enum ServerError 

#[non_exhaustive]
pub enum ServerError {
    TaskNotFound(TaskId),
    TaskNotCancelable(TaskId),
    InvalidParams(String),
    Serialization(Error),
    Http(Error),
    HttpClient(String),
    Transport(String),
    PushNotSupported,
    Internal(String),
    MethodNotFound(String),
    Protocol(A2aError),
    PayloadTooLarge(String),
    UnsupportedOperation(String),
    InvalidStateTransition {
        task_id: TaskId,
        from: TaskState,
        to: TaskState,
    },
}

Server framework error type.

Each variant maps to a specific A2A ErrorCode via to_a2a_error.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

TaskNotFound(TaskId)

The requested task was not found.

TaskNotCancelable(TaskId)

The task is in a terminal state and cannot be canceled.

InvalidParams(String)

Invalid method parameters.

Serialization(Error)

JSON serialization/deserialization failure.

Http(Error)

Hyper HTTP error.

HttpClient(String)

HTTP client-side error (e.g. push notification delivery).

Transport(String)

Transport-layer error.

PushNotSupported

The agent does not support push notifications.

Internal(String)

An internal server error.

MethodNotFound(String)

The requested JSON-RPC method was not found.

Protocol(A2aError)

An A2A protocol error propagated from the executor.

PayloadTooLarge(String)

The request body exceeds the configured size limit.

UnsupportedOperation(String)

The operation is not supported for the current task state (e.g. sending a message to a terminal task, subscribing to a completed task).

InvalidStateTransition

An invalid task state transition was attempted.

Fields

task_id: TaskId

The task ID.

from: TaskState

The current state.

to: TaskState

The attempted target state.

Implementations

impl ServerError

pub fn to_a2a_error(&self) -> A2aError

Converts this server error into an A2aError suitable for wire responses.

Mapping

Variant	ErrorCode
TaskNotFound	TaskNotFound
TaskNotCancelable	TaskNotCancelable
InvalidParams	InvalidParams
Serialization	ParseError
MethodNotFound	MethodNotFound
PushNotSupported	PushNotificationNotSupported
UnsupportedOperation	UnsupportedOperation
everything else	InternalError

Trait Implementations

impl Debug for ServerError

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

Formats the value using the given formatter.

impl Display for ServerError

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

Formats the value using the given formatter.

impl Error for ServerError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<A2aError> for ServerError

fn from(e: A2aError) -> ServerError

Converts to this type from the input type.

impl From<Error> for ServerError

fn from(e: Error) -> ServerError

Converts to this type from the input type.

impl From<Error> for ServerError

fn from(e: Error) -> ServerError

Converts to this type from the input type.