n8n errors / Schema
ERROR: Unknown top-level item key: pairedItems [item 0]
Cause
A node (often Google Sheets) emits an invalid 'pairedItems' key that the Code node's strict validator rejects (only json, binary, error, pairedItem, index are allowed).
Fix
Add a Code node before the failing node to delete the key: for (const item of $input.all()) { delete item.pairedItems; } return $input.all();. Permanently fix by upgrading to n8n v1.18.1+ which resolves the upstream Google Sheets bug.
Part of the Automation Error Index — n8n errors: browse all.
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