CODE_MODE_API_MISUSE

CODE_MODE_API_MISUSE

Error message

${namePrefix}uses mode: 'runOnceForEachItem' but calls $input.${disallowedInputMethod}(). $input.${disallowedInputMethod}() is only available in runOnceForAllItems (the default). Switch mode to runOnceForAllItems, or use $input.item / $json for per-item work.

What it means

CODE_MODE_API_MISUSE is a lint issue. When mode is 'runOnceForEachItem', lintJsCode() flags any call to $input.first(), $input.last(), $input.all(), or $input.itemMatching(n) — these only exist in runOnceForAllItems. The walker matches $input.<method>() specifically.

Source

Thrown at packages/@n8n/workflow-sdk/src/lint/code-node/js.ts:194

	if (sawForbiddenImport) {
		issues.push(
			lintIssue({
				code: 'CODE_NODE_FORBIDDEN_IMPORT',
				message:
					`${namePrefix}Code node imports a module unavailable in the sandbox (luxon, openai, langchain, …). ` +
					'Use JavaScript `Date`/`Intl`, `$now`/`$today`, existing workflow data, or dedicated AI nodes instead.',
				lintTarget: 'jsCode',
				nodeName: options.nodeName,
				parameterPath: 'jsCode',
			}),
		);
	}

	if (options.mode === 'runOnceForEachItem' && disallowedInputMethod !== undefined) {
		issues.push(
			lintIssue({
				code: 'CODE_MODE_API_MISUSE',
				message:
					`${namePrefix}uses mode: 'runOnceForEachItem' but calls $input.${disallowedInputMethod}(). ` +
					`$input.${disallowedInputMethod}() is only available in runOnceForAllItems (the default). ` +
					'Switch mode to runOnceForAllItems, or use $input.item / $json for per-item work.',
				lintTarget: 'jsCode',
				nodeName: options.nodeName,
				parameterPath: 'jsCode',
			}),
		);
	}

	if (hasNestedTemplateLiteral(ast)) {
		issues.push(
			lintIssue({
				code: 'CODE_NESTED_TEMPLATE_LITERAL',
				message:
					`${namePrefix}Code node uses nested template literals, which often break after save. ` +
					'Build multi-line strings with arrays joined by a runtime separator, e.g. ' +

View on GitHub (pinned to 5ac6606e81)

Solutions

Switch the Code node mode to runOnceForAllItems (the default) if you need $input.all()/first()/last().
Keep runOnceForEachItem and use $input.item / $json for per-item work instead.

Example fix

// before — mode: 'runOnceForEachItem'
return $input.all().map((i) => i.json.x);
// after — mode: 'runOnceForAllItems'
return $input.all().map((i) => i.json.x);
// (or keep per-item mode and use:)
// return $json.x;

Defensive patterns

Strategy: validation

Validate before calling

import { lintJsCode } from '@n8n/workflow-sdk/lint/code-node/js';
const issues = lintJsCode(jsCode, { mode: 'runOnceForEachItem' });
if (issues.some((i) => i.code === 'CODE_MODE_API_MISUSE')) {
  throw new Error('runOnceForEachItem cannot use $input.first/last/all/itemMatching; switch mode or use $input.item.');
}

Prevention

In runOnceForEachItem use $input.item / $json only.
If you need $input.all()/first()/last(), set mode to runOnceForAllItems.
Lint with the same mode the node will run in.

When it happens

Trigger: mode: 'runOnceForEachItem' combined with $input.all(), $input.first(), $input.last(), or $input.itemMatching(0) anywhere in jsCode.

Common situations: LLM mixes per-item mode with all-items APIs; developer toggles mode without updating the code body; copied snippet assumes all-items context.

Related errors

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/0a629d6035c13dc1. Report an issue: GitHub.