invalid-mark-as-lro-target

Id

@azure-tools/typespec-client-generator-core/invalid-mark-as-lro-target

Severity: warning

This diagnostic is issued when @markAsLro is applied to an operation that does not return a non-error model response.

Impact

• Area: Legacy LRO SDK metadata. Generation continues with the operation treated as a regular method because no model response is available for forced LRO metadata.
• Not affected: The service operation’s HTTP behavior and response type are unchanged.

❌ Incorrect Usage

@markAsLro
@post
op start(): string; // LRO marker requires a model response

Diagnostic Message

TCGC reports:

@markAsLro decorator can only be applied to operations that return a model. We will ignore this decorator.

✅ How to Fix

Apply @markAsLro only to operations that return a model, or remove the decorator.

model StartResponse {
  id: string;
}

@markAsLro
@post
op start(): StartResponse;

Suppression

This diagnostic should not be suppressed. Fix the target so it is a valid long-running operation, or remove @markAsLro.