n8n-io/n8n · error · Error

Planner produced invalid output after ${MAX_PLANNER_RETRIES

Error message

Planner produced invalid output after ${MAX_PLANNER_RETRIES + 1} attempts: ${lastError}

What it means

Error "Planner produced invalid output after ${MAX_PLANNER_RETRIES + 1} attempts: ${lastError}" thrown in n8n-io/n8n.

Source

Thrown at packages/@n8n/ai-workflow-builder.ee/src/agents/planner.agent.ts:175

				? [contextMessage]
				: [
						contextMessage,
						new HumanMessage(
							`Your previous output was invalid: ${lastError}. Please output a valid JSON plan with summary, trigger, and steps fields.`,
						),
					];

		const output = await agent.invoke({ messages }, config);
		const parsedPlan = plannerOutputSchema.safeParse(output.structuredResponse);
		if (parsedPlan.success) {
			plan = parsedPlan.data;
			break;
		}
		lastError = parsedPlan.error.message;
	}

	if (!plan) {
		throw new Error(
			`Planner produced invalid output after ${MAX_PLANNER_RETRIES + 1} attempts: ${lastError}`,
		);
	}
	const decisionValue: unknown = interrupt({ type: 'plan', plan });
	const decision = parsePlanDecision(decisionValue);

	if (decision.action === 'approve') {
		return {
			planDecision: 'approve',
			planOutput: plan,
			mode: 'build',
			planFeedback: null,
			planPrevious: null,
		};
	}

	if (decision.action === 'reject') {
		return {

View on GitHub (pinned to 5ac6606e81)

When it happens

Trigger: Thrown at packages/@n8n/ai-workflow-builder.ee/src/agents/planner.agent.ts:175 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/0ccf71cfe0fec760. Report an issue: GitHub.