FILTER_MISSING_COMBINATOR

FILTER_MISSING_COMBINATOR

Error message

${nodeRef} is missing 'combinator' in ${paramPath}. Add: combinator: 'and'

What it means

Error-level validator issue (code FILTER_MISSING_COMBINATOR) emitted when a Filter node's filter value has no 'combinator' key. The combinator ('and' / 'or') defines how multiple conditions are combined; omitting it leaves evaluation ambiguous, so the validator requires it explicitly.

Source

Thrown at packages/@n8n/workflow-sdk/src/workflow-builder/plugins/validators/filter-node-validator.ts:61

			originalName,
			parameterPath: `${paramPath}.options`,
		});
	}

	if (!Array.isArray(filterValue.conditions) || filterValue.conditions.length === 0) {
		issues.push({
			code: 'FILTER_MISSING_CONDITIONS',
			message: `${nodeRef} is missing or has empty 'conditions' array in ${paramPath}. Add at least one condition with leftValue, operator, and rightValue.`,
			severity: 'error',
			nodeName,
			originalName,
			parameterPath: `${paramPath}.conditions`,
		});
	}

	if (filterValue.combinator === undefined) {
		issues.push({
			code: 'FILTER_MISSING_COMBINATOR',
			message: `${nodeRef} is missing 'combinator' in ${paramPath}. Add: combinator: 'and'`,
			severity: 'error',
			nodeName,
			originalName,
			parameterPath: `${paramPath}.combinator`,
		});
	}

	return issues;
}

export const filterNodeValidator: ValidatorPlugin = {
	id: 'core:filter-node',
	name: 'Filter Node Validator',
	nodeTypes: FILTER_NODE_TYPES,
	priority: 40,

	validateNode(

View on GitHub (pinned to 5ac6606e81)

Solutions

Add combinator: 'and' (or 'or') to the filter value.
Confirm the combinator matches the intended logic across all conditions.
Re-run the validator to confirm the error clears.

Example fix

// before
filter({ options: {...}, conditions: [...] })
// after
filter({
  options: {...},
  conditions: [...],
  combinator: 'and'
})

Defensive patterns

Strategy: validation

Validate before calling

if (filterValue.combinator === undefined) {
  // error: add combinator: 'and' | 'or'
}

Type guard

function isCombinator(v: unknown): v is 'and' | 'or' {
  return v === 'and' || v === 'or';
}

Prevention

Always set combinator explicitly on Filter nodes with multiple conditions.
Do not rely on implicit defaults — make the logic visible.
Run the filter validator as part of local builds.

When it happens

Trigger: Defining a filter with conditions and options but no combinator; assuming a default combinator is inferred.

Common situations: Minimal filter config; LLM-generated filter that omitted the key; migration from a single-condition filter that never needed a combinator.

Related errors

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/9ba15efb4ad0caa9. Report an issue: GitHub.