n8n-io/n8n · error · NodeOperationError

${error}

Error message

${error}

What it means

Catch-all around executeWorkflow in the Retriever Workflow node: launching the sub-workflow threw. The raw error is normalized (json-serializable message) so it reliably reaches the execution log instead of being lost in serialization.

Solutions

1. Read the embedded message — sub-workflow crash or configuration error
2. Run the sub-workflow directly to reproduce and fix it

When it happens

Trigger: Thrown at packages/@n8n/nodes-langchain/nodes/retrievers/RetrieverWorkflow/RetrieverWorkflow.node.ts:408 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/bd24f914d030f92d. Report an issue: GitHub.

Appendix: source

Thrown at packages/@n8n/nodes-langchain/nodes/retrievers/RetrieverWorkflow/RetrieverWorkflow.node.ts:408

				let receivedData: ExecuteWorkflowData;
				try {
					receivedData = await this.executeFunctions.executeWorkflow(
						workflowInfo,
						items,
						config?.getChild(),
						{
							parentExecution: {
								executionId: workflowProxy.$execution.id,
								workflowId: workflowProxy.$workflow.id,
							},
							returnLastRunOnly: true, // Retrieved documents are the sub-workflow's final-run output, not its intermediate pipeline steps.
						},
					);
				} catch (error) {
					// Make sure a valid error gets returned that can by json-serialized else it will
					// not show up in the frontend
					throw new NodeOperationError(this.executeFunctions.getNode(), error as Error);
				}

				const receivedItems = receivedData.data?.[0] ?? [];

				const returnData: Document[] = [];
				for (const [index, itemData] of receivedItems.entries()) {
					const pageContent = objectToString(itemData.json);
					returnData.push(
						new Document({
							pageContent: `### ${index + 1}. Context data:\n${pageContent}`,
							metadata: {
								...baseMetadata,
								itemIndex: index,
								executionId: receivedData.executionId,
							},
						}),
					);
				}

View on GitHub (pinned to 5ac6606e81)