fix(protocol): add RequestAborted error code for AbortSignal cancellation

packages/core/src/errors/sdkErrors.ts

@@ -22,6 +22,8 @@ export enum SdkErrorCode {
     // Transport errors
     /** Request timed out waiting for response */
     RequestTimeout = 'REQUEST_TIMEOUT',
+    /** Request was aborted via AbortSignal */
+    RequestAborted = 'REQUEST_ABORTED',
     /** Connection was closed */
     ConnectionClosed = 'CONNECTION_CLOSED',
     /** Failed to send message */

packages/core/src/shared/protocol.ts

@@ -907,7 +907,14 @@ export abstract class Protocol<ContextT extends BaseContext> {
                     .catch(error => this._onerror(new Error(`Failed to send cancellation: ${error}`)));
 
                 // Wrap the reason in an SdkError if it isn't already
-                const error = reason instanceof SdkError ? reason : new SdkError(SdkErrorCode.RequestTimeout, String(reason));
+                let error: SdkError;
+                if (reason instanceof SdkError) {
+                    error = reason;
+                } else if (reason instanceof DOMException && reason.name === 'AbortError') {
+                    error = new SdkError(SdkErrorCode.RequestAborted, reason.message);
+                } else {
+                    error = new SdkError(SdkErrorCode.RequestAborted, String(reason));
+                }
                 reject(error);
             };
 

packages/core/test/shared/protocol.test.ts

@@ -209,6 +209,24 @@ describe('protocol tests', () => {
         }
     });
 
+    test('should throw RequestAborted (not RequestTimeout) when aborted via AbortSignal', async () => {
+        await protocol.connect(transport);
+        const mockSchema: ZodType<{ result: string }> = z.object({ result: z.string() });
+        const controller = new AbortController();
+
+        const requestPromise = testRequest(protocol, { method: 'example', params: {} }, mockSchema, {
+            signal: controller.signal,
+            timeout: 60_000
+        });
+
+        controller.abort(new DOMException('User cancelled', 'AbortError'));
+
+        const error = await requestPromise.catch((e: unknown) => e);
+        expect(error).toBeInstanceOf(SdkError);
+        expect((error as SdkError).code).toBe(SdkErrorCode.RequestAborted);
+        expect((error as SdkError).code).not.toBe(SdkErrorCode.RequestTimeout);
+    });
+
     test('should invoke onclose when the connection is closed', async () => {
         const oncloseMock = vi.fn();
         protocol.onclose = oncloseMock;