Enum ToolError 

pub enum ToolError {
    Edit(EditError),
    Skill(SkillRefusal),
    InvalidArguments {
        message: String,
    },
    NotFound {
        message: String,
    },
    Forbidden {
        message: String,
    },
    Retryable {
        message: String,
        retry_after_seconds: u64,
    },
    StagedStateChanged {
        message: String,
        entities: Vec<Value>,
    },
    Refused {
        code: ToolErrorCode,
        message: String,
        details: Map<String, Value>,
    },
    InsufficientScope {
        required: McpScope,
    },
    Internal(String),
}

Why a tool call failed. Mapped to a tool result or a JSON-RPC error by the protocol layer.

Variants

Edit(EditError)

An edit the engines rejected; shown to the agent with its fix.

Skill(SkillRefusal)

InvalidArguments

Fields

message: String

NotFound

Fields

message: String

Forbidden

The user’s role doesn’t allow this on that course or page.

Fields

message: String

Retryable

A dependency (validator, storage) is down or busy; the same call can be retried.

Fields

message: String

retry_after_seconds: u64

StagedStateChanged

Another call changed the staged state this call read, so nothing was staged; the call can be repeated after reading again.

Fields

message: String

entities: Vec<Value>

{entity_type, entity_id} of each entity that changed; empty when the whole changeset closed.

Refused

The call changed nothing because it would break a rule of publishing or reverting; code names the rule and details what to fix.

Fields

code: ToolErrorCode

message: String

details: Map<String, Value>

InsufficientScope

The token lacks a scope; answered with an HTTP 403 so the client can step up.

Fields

required: McpScope

Internal(String)

Implementations

impl ToolError

pub fn no_edit_rights() -> Self

The user’s roles don’t allow editing the course.

pub fn retryable(message: impl Into<String>, retry_after_seconds: u64) -> Self

A dependency is down or busy; the agent may repeat the same call after retry_after_seconds.

pub fn forbidden_or_internal( error: AuthorizationError, message: impl Into<String>, ) -> Self

A refusal with message when error is one; an internal error when the check couldn’t be made.

pub fn refused( code: ToolErrorCode, message: impl Into<String>, details: Value, ) -> Self

A ToolError::Refused with the fields of details, a JSON object.

pub fn into_json(self) -> Value

The error object of the result the agent gets. Dispatch answers insufficient scopes and internal errors with protocol errors instead.

pub fn into_result(self) -> ToolResult

The isError result the agent gets; see ToolError::into_json.

Trait Implementations

impl Debug for ToolError

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

Formats the value using the given formatter.

impl Display for ToolError

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

Formats the value using the given formatter.

impl Error for ToolError

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<AuthorizationError> for ToolError

fn from(error: AuthorizationError) -> Self

Converts to this type from the input type.

impl From<EditError> for ToolError

fn from(source: EditError) -> Self

Converts to this type from the input type.

impl From<ModelError> for ToolError

fn from(error: ModelError) -> Self

Converts to this type from the input type.

impl From<SkillRefusal> for ToolError

fn from(source: SkillRefusal) -> Self

Converts to this type from the input type.

impl From<ValidatorError> for ToolError

fn from(error: ValidatorError) -> Self

Converts to this type from the input type.