diff --git a/packages/cli/src/modules/instance-ai/eval/__tests__/eval-mocked-credentials-helper.test.ts b/packages/cli/src/modules/instance-ai/eval/__tests__/eval-mocked-credentials-helper.test.ts
index 356d13b6fa7..7f96c592917 100644
--- a/packages/cli/src/modules/instance-ai/eval/__tests__/eval-mocked-credentials-helper.test.ts
+++ b/packages/cli/src/modules/instance-ai/eval/__tests__/eval-mocked-credentials-helper.test.ts
@@ -415,11 +415,7 @@ describe('EvalMockedCredentialsHelper', () => {
 	});
 
 	describe('getDecrypted — schema synthesis when id is null', () => {
-		// Core's eval-mode bypass passes `{ id: null, name: type }` when a node
-		// has no credentials configured at all. The inner helper throws
-		// CredentialNotFoundError on a null id; the catch below schema-synthesizes
-		// (and applies the URL rewrite) so vendor SDK traffic stays inside the
-		// wire server instead of escaping to the real provider with 401.
+		// `{ id: null }` short-circuits to schema synthesis without delegating to the inner helper.
 		const propsSchema = [
 			{
 				name: 'apiKey',
@@ -441,7 +437,7 @@ describe('EvalMockedCredentialsHelper', () => {
 		function makeSynthesizingInner(): ICredentialsHelper {
 			return makeInner({
 				getCredentialsProperties: jest.fn().mockReturnValue(propsSchema),
-				// Inner throws on a null-id lookup → catch fires → schema synthesis.
+				// Not reached for a null id (short-circuits first); left rejecting so a regression fails loudly.
 				getDecrypted: jest.fn().mockRejectedValue(new CredentialNotFoundError('null', 'openAiApi')),
 			});
 		}
@@ -569,6 +565,65 @@ describe('EvalMockedCredentialsHelper', () => {
 		});
 	});
 
+	describe('no-id credential references — regression for "Found credential with no ID."', () => {
+		// Id-less refs (builder "set up later" placeholders, core's `{ id: null }`) make the real
+		// inner throw UnexpectedError, not CredentialNotFoundError — so the helper must synthesize, not delegate.
+		const propsSchema = [
+			{
+				name: 'apiKey',
+				displayName: 'API Key',
+				type: 'string' as const,
+				default: '',
+				typeOptions: { password: true },
+			},
+		];
+
+		it.each([
+			['null id (fully-unconfigured bypass)', { id: null, name: 'telegramApi' }],
+			['empty-string id (placeholder)', { id: '', name: 'Telegram cred' }],
+			['missing id (placeholder)', { name: 'Telegram cred' }],
+		])('synthesizes without delegating to inner — %s', async (_label, creds) => {
+			const inner = makeInner({
+				getCredentialsProperties: jest.fn().mockReturnValue(propsSchema),
+				// Stands in for core's UnexpectedError on a falsy id — fails loudly if the short-circuit regresses.
+				getDecrypted: jest.fn().mockRejectedValue(new Error('Found credential with no ID.')),
+			});
+			const helper = new EvalMockedCredentialsHelper(inner);
+
+			const result = await helper.getDecrypted(
+				fakeAdditionalData,
+				creds as INodeCredentialsDetails,
+				'telegramApi',
+				'manual',
+				{ node: fakeNode } as IExecuteData,
+			);
+
+			expect(result.__evalMockedCredential).toBe(true);
+			expect(inner.getDecrypted).not.toHaveBeenCalled();
+			expect(helper.mockedCredentials).toEqual([
+				{ nodeName: 'Telegram', credentialType: 'telegramApi', credentialId: undefined },
+			]);
+		});
+
+		it('still delegates (and surfaces the throw) when an id IS present', async () => {
+			// A present id whose lookup fails with a non-CredentialNotFoundError must still propagate.
+			const inner = makeInner({
+				getDecrypted: jest.fn().mockRejectedValue(new Error('database is down')),
+			});
+			const helper = new EvalMockedCredentialsHelper(inner);
+
+			await expect(
+				helper.getDecrypted(
+					fakeAdditionalData,
+					{ id: 'real-id', name: 'Telegram cred' },
+					'telegramApi',
+					'manual',
+				),
+			).rejects.toThrow('database is down');
+			expect(inner.getDecrypted).toHaveBeenCalled();
+		});
+	});
+
 	describe('authenticate', () => {
 		it('passes the request through unchanged for marker payloads', async () => {
 			const inner = makeInner();
diff --git a/packages/cli/src/modules/instance-ai/eval/eval-mocked-credentials-helper.ts b/packages/cli/src/modules/instance-ai/eval/eval-mocked-credentials-helper.ts
index bab3f96a7d8..827cf42ce7f 100644
--- a/packages/cli/src/modules/instance-ai/eval/eval-mocked-credentials-helper.ts
+++ b/packages/cli/src/modules/instance-ai/eval/eval-mocked-credentials-helper.ts
@@ -104,6 +104,21 @@ export class EvalMockedCredentialsHelper extends ICredentialsHelper {
 		raw?: boolean,
 		expressionResolveValues?: ICredentialsExpressionResolveValues,
 	): Promise<ICredentialDataDecryptedObject> {
+		// Id-less refs make the inner helper throw UnexpectedError (not CredentialNotFoundError),
+		// which the catch below won't handle — synthesize a mock here instead of delegating.
+		if (!nodeCredentials.id) {
+			this.mockedCredentials.push({
+				nodeName: executeData?.node?.name ?? 'unknown',
+				credentialType: type,
+				credentialId: undefined,
+			});
+			const synthesized = {
+				...buildEvalMockCredentials(this.inner.getCredentialsProperties(type)),
+				[MOCK_MARKER]: true,
+			} as ICredentialDataDecryptedObject;
+			return this.applyServerUrlRewrite(synthesized, type, nodeCredentials, executeData);
+		}
+
 		let credentials: ICredentialDataDecryptedObject;
 		try {
 			credentials = await this.inner.getDecrypted(
@@ -118,28 +133,13 @@ export class EvalMockedCredentialsHelper extends ICredentialsHelper {
 		} catch (error) {
 			if (!(error instanceof CredentialNotFoundError)) throw error;
 
+			// id present but absent from the DB — a bare marker stub is enough; URL rewrite still runs below.
 			this.mockedCredentials.push({
 				nodeName: executeData?.node?.name ?? 'unknown',
 				credentialType: type,
 				credentialId: nodeCredentials.id ?? undefined,
 			});
-
-			// When called with no credential id (eval-mode bypass for nodes
-			// with no credentials of any type configured), schema-synthesize
-			// so the wire-server URL rewrite below has a real `url` field to
-			// augment. Otherwise vendor SDK traffic would escape to the real
-			// provider with placeholder values and 401 at the wire layer.
-			// `buildEvalMockCredentials` is typed `Record<string, unknown>` —
-			// schema defaults can be richer than `CredentialInformation`, but
-			// at runtime emits only JSON-shaped values, which is what the
-			// rewrite path consumes.
-			credentials =
-				nodeCredentials.id === null
-					? ({
-							...buildEvalMockCredentials(this.inner.getCredentialsProperties(type)),
-							[MOCK_MARKER]: true,
-						} as ICredentialDataDecryptedObject)
-					: { [MOCK_MARKER]: true };
+			credentials = { [MOCK_MARKER]: true };
 		}
 
 		return this.applyServerUrlRewrite(credentials, type, nodeCredentials, executeData);