GPT Image 2 / 2.5 Generator

GPT Image 2 has no open weights. You cannot download it, so "in my ComfyUI workflow" is always going to mean "call it over the network." There are two doors: Comfy's official Partner Nodes (which need a Comfy account and prepaid credits) and an API-wrapper node pointed at a key you already own. This is the second door - a node for people who have an OpenAI-compatible relay key (New-API, One-API, and friends) and want to drop gpt-image-2 straight into a graph next to their local upscaler and masking.

To be clear about what it is: the node runs no model. It's an HTTP client dressed as a generator. Give it a base_url, an api_key, and a model name, and it POSTs your prompt to /v1/images/generations (text), /v1/images/edits (when you wire in reference images), or /v1/responses (if you force it). It picks the endpoint automatically from whether you've attached an image, returns a standard ComfyUI IMAGE tensor, and hands you a bonus INFO_JSON string with request diagnostics. The enthusiasm is easy to understand: GPT Image 2 dominated r/comfyui from April 2026, and since it's closed, API nodes like this are how it gets used seriously.

The inputs that actually matter

• api_key - required, and deliberately never persisted to disk. You retype it every session. Annoying, but it means your key can't leak out of a config file.
• base_url - the trap. The default is pre-filled with the author's own demo gateway (http://38.145.218.40:12001). You almost certainly want to replace it with your relay's address.
• model - free text, and it has to match the model name your relay has configured (gpt-image-2, openai/gpt-5.4-image-2, whatever alias the upstream uses).
• resolution × aspect_ratio - mutually exclusive, and this is the pack's best idea. 1:1 has no 4K, 16:9/9:16 have no 1K, 3:1 is 4K-only. The node hard-blocks illegal combos before they're sent (and a bundled front-end script makes the dropdown physically refuse them), because an illegal combo means burning a 5–15 minute request that comes back 502.
• quality (auto/low/medium/high), n (1–10), seed (−1 = random, omitted otherwise).
• edit_mode (generate/reference/outpaint) plus image_1…image_16 and reference_strength for the image-edit path.
• timeout (default 900s) and infinite_timeout (on by default). 4K/High genuinely takes 5–15 minutes; keep the timeout long.

What it doesn't do (read this twice)

negative_prompt, style_preset, enhance_prompt, and safety_check all exist in the UI, but GPT Image 2 doesn't accept any of them. The node prints a console notice and strips them before the request. Don't tune a negative prompt - put "avoid X" in the positive prompt instead. Same story with reference_strength: it reads like it should control style blending, but it's popped out of the payload. There's also no retry on 5xx or network errors, on purpose - retrying a paid generation means double-billing. Failures throw a RuntimeError with full diagnostics: HTTP status, server header, cf-ray, x-request-id, and the response body.

Install

ComfyUI Manager → Install via Git URL:

https://github.com/qianchi7/ComfyUI-SillyDream-GPT-Image-2.git

…or the manual way:

cd ComfyUI/custom_nodes
git clone https://github.com/qianchi7/ComfyUI-SillyDream-GPT-Image-2.git
pip install requests Pillow numpy

Then restart ComfyUI - not just refresh the page; custom nodes only load at startup. There are no model downloads; the dependencies are the three tiny ones above. Search the node palette for "GPT Image 2 Generator" (category "GPT Image 2"), and grab a starter from Workflow → Browse Templates → GPT-Image-2.

When it 502s

• 502/503: drop to 2K + medium to validate the chain, then raise again. If you must do 4K/High, check your reverse proxy's proxy_read_timeout (needs ≥1800s) or enable infinite_timeout.
• Read the diagnostics to locate the fault: a cf-ray header → Cloudflare/relay layer; server: nginx → your own proxy; server: Go → the New-API/One-API relay; server: OpenAI → the real upstream.
• HTTP 400 "Unknown parameter": the node auto-strips the offending field and retries; if it keeps failing, your model name doesn't match what the relay has.
• Can't connect: verify base_url opens from a browser. Portable installs need python_embeded\python.exe -m pip install requests Pillow numpy.

One trust note, because it's this category: an API-wrapper node holds your key and phones home by design, and this exact node shape was once used to ship malware (the LLMVISION incident). Nothing here is accusing this pack - it's MIT-licensed and the config handling is unusually careful about not persisting keys. Just actually look at the base_url you're pasting a paid key into. With a relay key in hand, this is the cleanest way to get gpt-image-2's typography and reference-image chops into a graph that otherwise never leaves your GPU.