n8n-io/n8n · error · Error

Invalid `--filter` value for

Error message

Invalid `--filter` value for "${key}": value cannot be empty

What it means

Value-validation error in parseFilters. It fires when a --filter value matched the key:value shape but the value part is empty or whitespace-only after trimming, e.g. --filter "do:". The key parsed fine; only the value is missing.

Solutions

1. Provide a non-empty value after the colon, e.g. --filter "do:some guidance".
2. Remove the empty --filter argument entirely if no filtering is needed.
3. Trim whitespace-only values; they count as empty.

When it happens

Trigger: Thrown at packages/@n8n/ai-workflow-builder.ee/evaluations/cli/argument-parser.ts:480 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/48c7a838aefe1878. Report an issue: GitHub.

Appendix: source

Thrown at packages/@n8n/ai-workflow-builder.ee/evaluations/cli/argument-parser.ts:480

}

function parseFilters(args: {
	filter: string[];
	notionId?: string;
	technique?: string;
}): LangsmithExampleFilters | undefined {
	const filters: LangsmithExampleFilters = {};

	for (const raw of args.filter) {
		const match = raw.match(/^(\w+):(.+)$/);
		if (!match) {
			throw new Error('Invalid `--filter` format. Expected: --filter "key:value"');
		}

		const [, key, valueRaw] = match;
		const value = valueRaw.trim();
		if (value.length === 0) {
			throw new Error(`Invalid \`--filter\` value for "${key}": value cannot be empty`);
		}
		switch (key) {
			case 'do':
				filters.doSearch = value;
				break;
			case 'dont':
				filters.dontSearch = value;
				break;
			case 'technique':
				filters.technique = value;
				break;
			case 'id':
				filters.notionId = value;
				break;
			default:
				throw new Error(`Unknown filter key "${key}". Expected one of: do, dont, technique, id`);
		}
	}

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