Enum McpError 

pub enum McpError {
    Rpc {
        code: i64,
        message: String,
        data: Option<Value>,
    },
    Closed(String),
    Timeout(u64),
    Aborted,
    Http {
        status: u16,
        message: String,
    },
    AuthRequired {
        challenge: Option<String>,
    },
    SessionExpired,
    SignInRequired,
    Network(String),
    Other(String),
}

Why an MCP request or connection failed. Messages match pi-mcp’s.

Variants

Rpc

The server answered with a JSON-RPC error, or sent something invalid.

Fields

code: i64

JSON-RPC error code.

message: String

The server’s message.

data: Option<Value>

Extra data the server attached.

Closed(String)

The connection is closed or not open.

Timeout(u64)

No response within the timeout.

Aborted

The caller cancelled the request.

Http

An HTTP request failed with a status.

Fields

status: u16

HTTP status.

message: String

Description with the start of the body.

AuthRequired

The server answered 401.

Fields

challenge: Option<String>

The WWW-Authenticate challenge.

SessionExpired

The server no longer knows the session (404 with a session id).

SignInRequired

The stored OAuth credentials cannot be used or refreshed, so the user has to sign in (again).

Network(String)

The request could not reach the server.

Other(String)

Anything else, such as a server process that could not start.

Implementations

impl McpError

pub fn closed() -> McpError

pi’s McpConnectionClosedError with its default message.

pub fn invalid(message: impl Into<String>) -> McpError

An invalid-request error with message.

pub fn status(&self) -> Option<u16>

The HTTP status, for HTTP failures.

pub fn is_transient(&self) -> bool

Network failures and overloaded or restarting servers, worth another attempt.

Trait Implementations

impl Clone for McpError

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 McpError

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

Formats the value using the given formatter.

impl Display for McpError

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

Formats the value using the given formatter.

impl Error for McpError

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 PartialEq for McpError

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for McpError