Send a transactional email. Provide subject+body OR a template UUID.

Track an event for a contact (creates the contact if missing). Used to drive workflows and segment filters. Requires PLUNK_PUBLIC_KEY (pk_*) to be set — /v1/track is gated by the public key, not the secret key.

Validate that an email address is deliverable.

List contacts. Supports cursor pagination, search (case-insensitive email substring), subscription-state filter, and column sort. subscribed, sort=email|createdAt, and dir require Plunk v0.12+.

Get a single contact by UUID.

Create or upsert a contact by email. Emails are normalized server-side (case + whitespace) on v0.12+, so you don't need to lowercase or trim client-side.

Update fields on an existing contact (PATCH). Pass email to change the address — returns 409 if another contact already uses it. In data, null deletes a key, empty strings are ignored, reserved keys are filtered out.

Delete a contact by UUID.

Subscribe a contact via their public id (the id embedded in unsubscribe links, NOT the regular UUID). For batch subscribes by regular id, use plunk_bulk_subscribe_contacts.

Unsubscribe a contact via their public id. For batch unsubscribes by regular id, use plunk_bulk_unsubscribe_contacts.

Upload an image (e.g. for use in templates or campaigns). Pass the file as base64. Note: the underlying endpoint is multipart; this tool sends a JSON shim — if your Plunk version requires multipart, use the dashboard upload flow.