Struct ValidationError 

pub struct ValidationError {
    pub code: ValidationErrorCode,
    pub field: String,
    pub message: String,
    pub expected: Option<String>,
    pub actual: Option<Value>,
    pub context: Option<Value>,
}

Available on non-WebAssembly only.

Structured validation error with elicitation support

Fields

code: ValidationErrorCode

The error code

field: String

The field that failed validation

message: String

Human-readable error message

expected: Option<String>

Expected format/value description

actual: Option<Value>

The actual value that failed (for debugging)

context: Option<Value>

Additional context for the error

Implementations

impl ValidationError

pub fn new(code: ValidationErrorCode, field: impl Into<String>) -> Self

Create a new validation error

pub fn expected(self, expected: impl Into<String>) -> Self

Set the expected value/format description

pub fn actual(self, actual: impl Into<Value>) -> Self

Set the actual value that failed validation

pub fn context(self, context: impl Into<Value>) -> Self

Set additional context

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

Set a custom message

pub fn to_json(&self) -> Value

Convert to a JSON value for elicitation

pub fn to_error(&self) -> Error

Convert to an MCP Error

Trait Implementations

impl Clone for ValidationError

fn clone(&self) -> ValidationError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ValidationError

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

Formats the value using the given formatter.