Klaviyo

At a glance

Availability: Experimental (how to enable).
Auth: API key.
Connection: The key from KLAVIYO_API_KEY is sent as the Klaviyo-API-Key prefixed Authorization header.
Docs: https://developers.klaviyo.com/en/reference/api_overview

Set these per environment. See Connect an integration.

Variable	Required	Description
`KLAVIYO_API_KEY`	Yes	Klaviyo private API key (starts with pk_) Docs.

Sign in to Klaviyo: Go to https://www.klaviyo.com and sign in. A free account is sufficient for testing.
Create a private API key: Open Settings → Account → API Keys (https://www.klaviyo.com/settings/account/api-keys) and create a private key. Grant it read/write access to Profiles, Lists, Segments, Metrics, and Events.
Set the environment variable: Add the key to your .env as KLAVIYO_API_KEY=pk_…
Verify access: Run the List Lists tool to confirm the key works.

Klaviyo authenticates with ‘Authorization: Klaviyo-API-Key <key>’ - not a Bearer token
Every request requires a ‘revision’ header; tools default it to 2026-04-15

Tool	Access	Description
List Profiles	Read	List customer profiles
Get Profile	Read	Get a customer profile by ID
Create Profile	Write	Create a new customer profile
List Lists	Read	List marketing lists
List Segments	Read	List audience segments
List Metrics	Read	List tracked event metrics (e.g. Placed Order, Opened Email)
Create Event	Write	Track a custom event for a profile