Keys and regions

Every node page has a Keys needed row. This page explains how those keys relate to regions and models.

Which key a node needs

Nodes	Key	Region
Seedream, Seedance, Video Query Tasks, BytePlus LLM	ModelArk API key	ap-southeast-1 or eu-west-1
Create Image, Video and Audio Asset, Asset Library	ModelArk API key and IAM access key and secret key	Follows the ModelArk region
Seed Audio, Seed Speech TTS, ASR, Voice Clone	Seed Speech API key	ap-southeast-1 only
vCube Video Enhance, Video Smoothness Enhance, Image Quality Enhance	AI MediaKit API key	ap-southeast-1 only

The keys are separate products and never interchangeable. Using a ModelArk API key on a speech node gives an Invalid Seed Speech API key error. How to create and save each key: API keys.

Regions

ModelArk has two regions:

• ap-southeast-1 (Singapore), the default.
• eu-west-1.

A ModelArk API key belongs to the region where you created it. Pick the same region in Settings → BytePlus next to the key. If they do not match, BytePlus answers Invalid API Key (401), and Settings refuses to save the key.

Seed Speech and AI MediaKit run in ap-southeast-1 only. They have no region setting.

Note

The region picked in Settings is saved as BYTEPLUS_REGION. An environment variable with that name wins over the file, and Settings then refuses to save a different region. Change or remove the variable and restart ComfyUI, or pick the region it names.

Models are activated per region

Each model must be activated in the ModelArk console for the region you use. A model you have not activated fails with has not activated the model.

Some models are not offered in every region. Seedream 5.0 Lite is not available in eu-west-1. If you pick it there, the node stops before sending anything and tells you to choose another model or region.

Changing a key takes effect at once

You do not need to restart ComfyUI after you save, replace or remove a key in Settings, or after you edit user/.env. The pack reads the file again whenever it changes and rebuilds its connection when the key or region changes. The same holds for the IAM access key and secret key used by the asset library.

An environment variable is read when ComfyUI starts, so changing one needs a restart.

Caching

ComfyUI caches a node’s result by its input values. The key is not an input. If you run an unchanged workflow after changing a key, ComfyUI reuses the cached result and sends no new request. Change a prompt or seed to force a fresh run.

Where the key is stored

Keys live in user/.env in your ComfyUI folder, written so that, where your system supports it, only you can read it. They are not in workflows, node outputs or logs. Settings can only show whether a key is set and its last four characters.