ComfyUI-Imagent
BYOK OpenAI image generation and editing nodes for ComfyUI.
Bring your own OpenAI API key — calls go directly to OpenAI, no proxy, no extra credits.
✨ Features
- 🖼️ Two nodes — Imagent: OpenAI Image (text-to-image) and Imagent: OpenAI Image Edit (edit, inpaint, multi-reference compose).
- 🤖 Current gpt-image models —
gpt-image-2.5-flare,gpt-image-2.5-sunburst,gpt-image-2. - ✍️ Text-to-image with full control over size, quality, background, and output format.
- 🎨 Edit + inpaint (mask) — supply a mask to repaint a specific region; white pixels mark the area to edit.
- 🔗 Multi-reference compositing — feed up to 16 reference images to the edit node (auto-growing input).
- 🎛️ Per-model UI — the
modelwidget is dynamic: switching models swaps the size list and shows only the options that model supports (no invalid combos). - 🏞️ Up to 8 images per call — batch generation in a single node execution.
- 🛡️ Optional content moderation —
auto(default) orlow. - 🔑 BYOK — your own OpenAI API key, your own costs. Unlike ComfyUI's built-in OpenAI nodes (which route through ComfyUI's paid proxy), Imagent calls the OpenAI API directly. No proxy, no per-image credit markup.
- 🚫 DALL·E intentionally excluded — all DALL·E models were shut down by OpenAI in 2026.
📦 Installation
Requires ComfyUI ≥ 0.23.0 — the nodes use the
comfy_apiIO schema (DynamicCombo) for the per-model UI.
Option A — ComfyUI Manager (recommended)
Open ComfyUI Manager → Custom Nodes Manager, search for Imagent, click Install, and restart ComfyUI.
Option B — git clone
cd ComfyUI/custom_nodes
git clone https://github.com/agarzon/ComfyUI-Imagent.git
pip install -r ComfyUI-Imagent/requirements.txt
Restart ComfyUI.
🔑 API key
Imagent reads your key in this order:
- Environment variable (preferred): set
OPENAI_API_KEYbefore launching ComfyUI. config.json: copyconfig.example.json→config.json(gitignored) in the extension directory and add your key.
Note: OpenAI may require API Organization Verification before gpt-image models can be called. If your key is valid but you receive an authorization error, complete verification in the OpenAI dashboard — the error message logged to the ComfyUI console will tell you.
🧩 Nodes
🤖 Imagent: OpenAI Image
Text-to-image generation via images.generate.
| Parameter | Type | Values / Notes |
|---|---|---|
prompt |
STRING | Text description of the image to generate |
model |
DynamicCombo | gpt-image-2.5-flare (default), gpt-image-2.5-sunburst, gpt-image-2. Switching the model swaps the options below. |
↳ size |
COMBO | auto, the three base sizes, five high-res presets, and custom. |
↳↳ custom_width / custom_height |
INT | Appear only when size = custom. 480–3840, step 16; both multiples of 16; aspect ≤ 3:1; total pixels 655,360–8,294,400. |
↳ background |
COMBO | gpt-image-2.5: auto, opaque, transparent (needs png/webp). gpt-image-2: auto, opaque. |
quality |
COMBO | auto, low, medium, high, plus xhigh / max on gpt-image-2.5 (other models fall back to high). |
output_format |
COMBO | png, jpeg, webp |
output_compression |
INT | 0–100. Applied only for jpeg and webp. |
moderation |
COMBO | auto (default), low. Sent only when not auto. |
n |
INT | 1–8 images per call |
Rows marked ↳ live inside the dynamic model widget (appear only for models that support them); ↳↳ rows are nested one level deeper and appear only when their parent option is selected.
No
seedwidget: OpenAI's image API has no seed, so it can't make outputs reproducible. ComfyUI's normal input-based caching applies — re-queuing an unchanged graph returns the cached image; change the prompt (or any input) to regenerate.
Outputs: image (IMAGE tensor, batch of n) and mask (MASK tensor). Errors are logged to the ComfyUI console.
ComfyUI's IMAGE type is RGB, so when background = transparent the alpha channel comes out on
mask instead — following the LoadImage convention, mask = 1 - alpha, meaning a transparent
region reads as selected (1.0). The image preview will look black in those regions; that is the
alpha being discarded for display, not a failed generation. To get a transparent file, feed
image and mask into Join Image with Alpha (it inverts the mask internally, so no
InvertMask in between) and save the result. Opaque output gives an all-zero mask.
🤖 Imagent: OpenAI Image Edit
Image editing, inpainting, and multi-reference compositing via images.edit.
| Parameter | Type | Values / Notes |
|---|---|---|
prompt |
STRING | Description of the desired edit |
model |
DynamicCombo | Same three models; switching swaps the options below. |
↳ size |
COMBO | Same as the generate node. |
↳↳ custom_width / custom_height |
INT | Appear only when size = custom. Same rules as the generate node. |
↳ background |
COMBO | gpt-image-2.5: auto/opaque/transparent; gpt-image-2: auto/opaque. |
images |
IMAGE (auto-grow) | Reference image(s) to edit — grows up to 16 slots; at least one required. |
quality |
COMBO | auto, low, medium, high, plus xhigh / max on gpt-image-2.5. |
output_format |
COMBO | png, jpeg, webp |
moderation |
COMBO | auto (default), low |
n |
INT | 1–8 images per call |
mask (optional) |
MASK | White = region to edit. Inpainting requires exactly one reference image. |
Rows marked ↳ live inside the dynamic model widget; ↳↳ rows appear only when their parent option is selected.
No
input_fidelitywidget: every model shipped here always uses high input fidelity, and passing the parameter is an error. It only applied to the retired gpt-image-1.x models.
Outputs: image (IMAGE tensor, batch of n) and mask (MASK tensor). Errors are logged to the ComfyUI console.
ComfyUI's IMAGE type is RGB, so when background = transparent the alpha channel comes out on
mask instead — following the LoadImage convention, mask = 1 - alpha, meaning a transparent
region reads as selected (1.0). The image preview will look black in those regions; that is the
alpha being discarded for display, not a failed generation. To get a transparent file, feed
image and mask into Join Image with Alpha (it inverts the mask internally, so no
InvertMask in between) and save the result. Opaque output gives an all-zero mask.
Quick-start recipes:
- Edit: connect one image to
images, write aprompt, leavemaskdisconnected. - Inpaint: connect one image +
mask(white = area to repaint), write aprompt. - Multi-reference: connect several images (the input grows as you wire them up), write a
prompt. Mask not supported for multi-image calls.
🛠️ Development
python3 -m venv .venv
.venv/bin/pip install -e ".[test]"
.venv/bin/pytest -q
Smoke testing with Docker
Set your API key first — either export OPENAI_API_KEY in your shell, or copy config.example.json → config.json and add your key. Then:
docker compose -f docker/docker-compose.yml up -d --build
ComfyUI will be available at http://localhost:8188 with Imagent pre-loaded. For Python changes, restart the container. The repo is bind-mounted into the container's custom_nodes/ directory.
🐾 The story behind the name
Imagent = image + agent. A small model-driven agent that images things into existence — and edits them once they're there.
It comes from Wallrus, whose own name blends a social wall with a walrus. Two friendly ideas, one tool: straightforward, reliable image generation without the middleman.
💙 Sponsored by Wallrus
ComfyUI-Imagent is proudly sponsored by Wallrus. If Imagent makes your ComfyUI workflow nicer, go say hi. 👋
📄 License
MIT © 2026 Alexander Garzon
