Directive to immediately emit a tool error result signal.
Used when a tool cannot be executed (e.g., unknown tool name, configuration error). This directive ensures the Machine receives a tool_result signal and doesn't deadlock waiting for a response that will never arrive.
Unlike ToolExec, this directive does not spawn a task - it synchronously emits
an error signal back to the agent.
Summary
Functions
Create a new EmitToolError directive.