fix(core): Route split in batches chains through loop output (#32968)

packages/@n8n/workflow-sdk/src/workflow-builder.integration.test.ts

@@ -681,6 +681,36 @@ describe('New SDK API', () => {
 			// Process Item loops back to Split In Batches via nextBatch()
 			expect(json.connections['Process Item'].main[0]![0].node).toBe('Process Batches');
 		});
+
+		it('chains nodes after a bare splitInBatches builder from the loop output', () => {
+			const t = createTrigger('Start');
+			const defineScenarios = createNode('Define Scenarios');
+			const loop = splitInBatches({
+				version: 3,
+				config: {
+					name: 'Loop Each Item',
+					parameters: { batchSize: 1, options: {} },
+				},
+			});
+			const generatePrompt = createNode('Generate Prompt');
+			const extractPrompt = createNode('Extract Prompt');
+			const logResult = createNode('Log Result');
+
+			const wf = workflow('test', 'Agentic AI Image Generator')
+				.add(t)
+				.to(defineScenarios)
+				.to(loop)
+				.to(generatePrompt)
+				.to(extractPrompt)
+				.to(logResult)
+				.to(nextBatch(loop));
+
+			const json = wf.toJSON();
+
+			expect(json.connections['Loop Each Item'].main[0] ?? []).toEqual([]);
+			expect(json.connections['Loop Each Item'].main[1]![0].node).toBe('Generate Prompt');
+			expect(json.connections['Log Result'].main[0]![0].node).toBe('Loop Each Item');
+		});
 	});
 
 	describe('API Integration: Complete Workflow Examples', () => {

packages/@n8n/workflow-sdk/src/workflow-builder.ts

@@ -345,8 +345,9 @@ class WorkflowBuilderImpl implements WorkflowBuilder {
 				}
 			}
 
-			this._currentNode = headName;
-			this._currentOutput = 0;
+			const continuation = thenHandler.handleThen?.(nodeOrComposite, headName, 0, ctx);
+			this._currentNode = continuation?.currentNode ?? headName;
+			this._currentOutput = continuation?.currentOutput ?? 0;
 			return this;
 		}
 

packages/@n8n/workflow-sdk/src/workflow-builder/plugins/composite-handlers/split-in-batches-handler.ts

@@ -130,8 +130,30 @@ export const splitInBatchesHandler: CompositeHandlerPlugin<SplitInBatchesBuilder
 			processingSibBuilders.delete(input);
 		}
 	},
+
+	handleThen(
+		input: SplitInBatchesBuilderShape,
+		currentNode: string,
+	): {
+		currentNode: string;
+		currentOutput: number;
+	} {
+		return {
+			currentNode,
+			currentOutput: hasConfiguredTargets(input) ? 0 : 1,
+		};
+	},
 };
 
+function hasConfiguredTargets(input: SplitInBatchesBuilderShape): boolean {
+	return (
+		'_doneTarget' in input ||
+		'_eachTarget' in input ||
+		(input._doneBatches !== undefined && input._doneBatches.length > 0) ||
+		(input._eachBatches !== undefined && input._eachBatches.length > 0)
+	);
+}
+
 /**
  * Process named syntax: splitInBatches(sibNode, { done: ..., each: ... })
  */