CatsAPI Seedream 5 Pro

Seedream 5 Pro is the flagship tier of ByteDance's image line, and this node is the door into it from ComfyUI. If you've read the Lite article, here's the short version: it's the same node in every way that matters - same inputs, same outputs, same wrapper, one different model key under the hood. Pro is the version you pay up for when the render has to be the good one: a client shot, a hero image, a portfolio piece. Lite is for drafts and experiments.

Why you'd reach for it

Seedream has no open weights, and Pro is the strongest member of a family you can't download. For anything that needs that closed-model quality inside a workflow - then composited, upscaled, or masked by your local nodes - this is how it gets there. The whole trade is on the table: no GPU, no VRAM dance, but every run costs coins, and your prompt leaves the machine to a server whose content policy is ByteDance's, not yours.

How it works

Identical machinery to the rest of the CatsAPI pack: the node asks the server what a run will cost, checks your balance and the max_coins cap, submits the prompt, polls until the job completes, downloads the PNGs into ComfyUI/output/catsapi/, and converts them to an IMAGE tensor. The code-level difference between Pro and Lite is literally one line - the model key seedream5Pro instead of seedream5Lite. Everything downstream is shared.

The inputs that matter

• prompt - multiline; the whole job.
• image_size - square (default) or portrait/landscape 4:3 / 16:9. There's no resolution or quality input; imageSize is all Seedream 5 accepts.
• num_images - 1 to 4 per run.
• seed - -1 leaves it to the API; set a non-negative value to reproduce a result.
• max_coins - the spending gate.
• reference_image - up to 4 images; a hard error beyond that.
• api_key_override - leave empty on your own box.

Outputs

images (the IMAGE tensor), file_paths (the downloaded PNG paths as JSON), cost_coins, task_id, metadata. Wire images straight into Preview Image or the next stage of your graph.

Installing

cd ComfyUI/custom_nodes
git clone https://github.com/maodeyu180/ComfyUI_Catsapi.git

Restart, then:

export CATSAPI_API_KEY=cats-your-key
python main.py

(~/.catsapi.env is an alternative.) No pip install needed - the client is pure stdlib.

Common issues

• Pro costs more than Lite - that's the whole point of the tiering, and cost_coins tells you the difference per run. Prototype on Lite, then switch this node in once the prompt is right.
• No reproduction - seed at -1 randomizes; set it.
• Reference batch too big - more than 4 into reference_image is a deliberate hard error.
• Key problems - the key must start with cats-, and any key with ... in it is rejected before sending.

As with the rest of this pack, the honest note: it's a young first-party integration with zero Reddit footprint. Inspect the small source if you're the paranoid sort, keep the key in an env var, and never share a workflow with api_key_override filled in, because it's baked into the JSON.