Enum ParseMessageError 

pub enum ParseMessageError {
    BatchUnsupported,
    Json(Error),
}

Error returned by parse_message_typed for the cases the untagged JsonRpcMessage enum can’t distinguish on its own.

JsonRpcMessage is #[serde(untagged)] over Request/Response/Notification. A top-level JSON array (a JSON-RPC §7 batch) fails serde’s variant match with a generic “data did not match any variant” diagnostic; MCP 2025-11-25 deprecates batches, so callers want to respond with a clear -32600 Invalid Request rather than echoing serde’s text.

Variants

BatchUnsupported

Top-level JSON array (deprecated batch shape).

Json(Error)

Anything else (parse error, unknown variant, etc.).

Trait Implementations

impl Debug for ParseMessageError

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

Formats the value using the given formatter.

impl Display for ParseMessageError

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

Formats the value using the given formatter.

impl Error for ParseMessageError

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<Error> for ParseMessageError

fn from(e: Error) -> Self

Converts to this type from the input type.