Klaviyo Common Errors

Overview

Quick reference for the most common Klaviyo API errors with real error payloads, root causes, and solutions. Because Klaviyo returns JSON:API errors (a status code plus a structured errors[] array), this skill walks you from a raw exception to a targeted fix: extract the status code, match it against the catalog, apply the documented remedy.

The full per-status-code catalog and the SDK-level failure table live in references/ to keep this workflow scannable — drill in once you know which status code you are chasing.

Prerequisites

• klaviyo-api SDK installed (npm install klaviyo-api — note: not @klaviyo/sdk)
• A private API key (pk_*) exported as KLAVIYO_PRIVATE_KEY
• Access to the application logs where the failed request was recorded, so you can Read the stack trace and Grep for the status code and error code