Enum ServerError 

#[non_exhaustive]
pub enum ServerError {
    Protocol(Box<Error>),
    Core(RegistryError),
    Transport(TransportError),
    Handler {
        message: String,
        context: Option<String>,
    },
    Configuration {
        message: String,
        key: Option<String>,
    },
    Authentication {
        message: String,
        method: Option<String>,
    },
    Authorization {
        message: String,
        resource: Option<String>,
    },
    RateLimit {
        message: String,
        retry_after: Option<u64>,
    },
    Lifecycle(String),
    Shutdown(String),
    Middleware {
        name: String,
        message: String,
    },
    Registry(String),
    Routing {
        message: String,
        method: Option<String>,
    },
    NotFound {
        resource: String,
    },
    Internal(String),
    Io(Error),
    Serialization(Error),
    Timeout {
        operation: String,
        timeout_ms: u64,
    },
    ResourceExhausted {
        resource: String,
        current: Option<usize>,
        max: Option<usize>,
    },
}

Comprehensive server error types

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.

Protocol(Box<Error>)

Protocol-level error from client or protocol layer

This variant preserves the original protocol error, including error codes like -1 for user rejection. This ensures transparency when forwarding client errors (e.g., sampling/elicitation rejections) back through the server to calling clients.

When converting to turbomcp_protocol::Error, this variant is unwrapped directly to preserve error semantics and codes.

Core(RegistryError)

Core errors

Transport(TransportError)

Transport layer errors

Handler

Handler registration errors

Fields

message: String

Error message

context: Option<String>

Optional error context

Configuration

Configuration errors

Fields

message: String

Error message

key: Option<String>

Configuration key that caused the error

Authentication

Authentication errors

Fields

message: String

Error message

method: Option<String>

Authentication method that failed

Authorization

Authorization errors

Fields

message: String

Error message

resource: Option<String>

Resource being accessed

RateLimit

Rate limiting errors

Fields

message: String

Error message

retry_after: Option<u64>

Retry after seconds

Lifecycle(String)

Server lifecycle errors

Shutdown(String)

Server shutdown errors

Middleware

Middleware errors

Fields

name: String

Middleware name

message: String

Error message

Registry(String)

Registry errors

Routing

Routing errors

Fields

message: String

Error message

method: Option<String>

Request method that failed

NotFound

Resource not found

Fields

resource: String

Resource that was not found

Internal(String)

Internal server errors

Io(Error)

IO errors

Serialization(Error)

Serialization errors

Timeout

Timeout errors

Fields

operation: String

Operation that timed out

timeout_ms: u64

Timeout in milliseconds

ResourceExhausted

Resource exhaustion

Fields

resource: String

Resource type

current: Option<usize>

Current usage

max: Option<usize>

Maximum allowed

Implementations

impl ServerError

pub fn handler(message: impl Into<String>) -> Self

Create a new handler error

pub fn handler_with_context( message: impl Into<String>, context: impl Into<String>, ) -> Self

Create a handler error with context

pub fn configuration(message: impl Into<String>) -> Self

Create a new configuration error

pub fn configuration_with_key( message: impl Into<String>, key: impl Into<String>, ) -> Self

Create a configuration error with key

pub fn authentication(message: impl Into<String>) -> Self

Create a new authentication error

pub fn authentication_with_method( message: impl Into<String>, method: impl Into<String>, ) -> Self

Create an authentication error with method

pub fn authorization(message: impl Into<String>) -> Self

Create a new authorization error

pub fn authorization_with_resource( message: impl Into<String>, resource: impl Into<String>, ) -> Self

Create an authorization error with resource

pub fn rate_limit(message: impl Into<String>) -> Self

Create a new rate limit error

pub fn rate_limit_with_retry( message: impl Into<String>, retry_after: u64, ) -> Self

Create a rate limit error with retry after

pub fn middleware(name: impl Into<String>, message: impl Into<String>) -> Self

Create a new middleware error

pub fn routing(message: impl Into<String>) -> Self

Create a new routing error

pub fn routing_with_method( message: impl Into<String>, method: impl Into<String>, ) -> Self

Create a routing error with method

pub fn not_found(resource: impl Into<String>) -> Self

Create a not found error

pub fn timeout(operation: impl Into<String>, timeout_ms: u64) -> Self

Create a timeout error

pub fn resource_exhausted(resource: impl Into<String>) -> Self

Create a resource exhausted error

pub fn resource_exhausted_with_usage( resource: impl Into<String>, current: usize, max: usize, ) -> Self

Create a resource exhausted error with usage info

pub const fn is_retryable(&self) -> bool

Check if this error is retryable

pub const fn is_fatal(&self) -> bool

Check if this error should cause server shutdown

pub fn error_code(&self) -> i32

Get error code for JSON-RPC responses

Trait Implementations

impl Debug for ServerError

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

Formats the value using the given formatter.

impl Display for ServerError

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

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<Box<Error>> for ServerError

fn from(core_error: Box<Error>) -> Self

Converts to this type from the input type.

impl From<Error> for ServerError

fn from(source: Error) -> Self

Converts to this type from the input type.

impl From<Error> for ServerError

fn from(source: Error) -> Self

Converts to this type from the input type.

impl From<RegistryError> for ServerError

fn from(source: RegistryError) -> Self

Converts to this type from the input type.

impl From<ServerError> for Box<Error>

This conversion preserves protocol errors directly when they come from clients (ServerError::Protocol variant), ensuring error codes like -1 for user rejection are maintained through the server layer.

Error Code Preservation

When a client returns an error (e.g., user rejects sampling with code -1), the server receives it as ServerError::Protocol(Error{ kind: UserRejected }). This conversion unwraps it directly, preserving the original error code when the error is sent back to calling clients.

fn from(server_error: ServerError) -> Self

Converts to this type from the input type.

impl From<ToolTimeoutError> for ServerError

fn from(timeout_error: ToolTimeoutError) -> Self

Converts to this type from the input type.

impl From<TransportError> for ServerError

fn from(source: TransportError) -> Self

Converts to this type from the input type.