Use Inferway H3 video in ComfyUI

Before you start

1. ComfyUI 0.35.0 or later, running on Python 3.10 or later. The ComfyUI startup log prints both versions.
2. An Inferway API key: sign in and create one under Console → Keys.
3. Account balance. Each generated video is billed; the pricing page lists the current price.

Step 1 · Install the node pack

With ComfyUI-Manager: open Custom Nodes Manager, search for Inferway H3, click Install, then restart ComfyUI. If the version column only offers nightly, install that: it is the latest published code.

Manually, if Manager is unavailable or refuses the install: clone the repository into custom_nodes and install its one dependency with the same Python that runs ComfyUI.

cd ComfyUI/custom_nodes
git clone https://github.com/inferway/comfyui-inferway inferway-comfy
# Use the Python that runs ComfyUI
# (Windows portable build: ..\..\python_embeded\python.exe)
python -m pip install -r inferway-comfy/requirements.txt

Step 2 · Set your API key

The nodes have no API key field, so a key never ends up in a workflow file you share. They read the INFERWAY_API_KEY environment variable of the ComfyUI process: set it, then restart ComfyUI.

ComfyUI Desktop on Windows: run setx INFERWAY_API_KEY "your-key" once in a terminal, then restart the app. ComfyUI Desktop on macOS: run launchctl setenv INFERWAY_API_KEY "your-key", then restart the app; repeat after each reboot.

# macOS / Linux: in the shell that starts ComfyUI
export INFERWAY_API_KEY="your-key"
python main.py

# Windows portable: add to run_nvidia_gpu.bat (or run_cpu.bat),
# above the line that starts ComfyUI
set INFERWAY_API_KEY=your-key

Step 3 · Check the nodes loaded

After the restart, double-click the canvas and search for Inferway. Three nodes should appear. Inferway H3 Generate creates a video. Inferway H3 Resume fetches the video of an existing task without creating or billing a new one. Inferway H3 Cancel cancels a task that is still running on Inferway.

Step 4 · Generate your first video

First and last frame: open first-last-frame.json from the same folder, load an opening and a closing image, and the model generates the shot between them. Image modes work only while the model list advertises them. The node checks before it creates a task, so an unavailable mode is never billed.

1. Download the text-to-video workflow t2v.json from https://github.com/inferway/comfyui-inferway/blob/main/workflows/ui and open it in ComfyUI with Ctrl+O.
2. Edit the prompt. Choose a duration of 5 to 10 seconds and a resolution of 1344×768 or 768×1344.
3. Click Run. Generation usually takes a few minutes; the MP4 is saved under ComfyUI's output/video folder.

Stopping and resuming without paying twice

ComfyUI's Stop button, and the node's local wait timeout, only stop ComfyUI from waiting. The task keeps running on Inferway and is billed when it completes. To stop the task itself, run Inferway H3 Cancel with its interaction ID; the node reports whether you were charged.

If the connection drops, the browser closes, or the wait times out, do not click Run again: that creates and bills a second task. Find the interaction ID in the console's video history, or run python -m inferway_comfy history --limit 20 with the Python that runs ComfyUI, then fetch the video with Inferway H3 Resume.

Troubleshooting

1. The pack shows IMPORT FAILED, or no Inferway node appears: check that ComfyUI runs on Python 3.10 or later and that the dependency was installed with that same Python, then restart.
2. The node reports an invalid API key: the ComfyUI process did not receive INFERWAY_API_KEY. Set it as in step 2 and restart ComfyUI; a running ComfyUI does not pick up a newly set variable.
3. The node reports that the mode is unavailable: the image mode you wired is not offered right now. Use text-to-video, or first and last frame while it is listed.
4. The node reports a mode conflict: first/last frame images and reference images were wired to the same node. Use one kind per task.
5. ComfyUI-Manager refuses the install: install manually as in step 1.
6. Inferway is not in ComfyUI's built-in API node list: that list only contains nodes that ship inside ComfyUI itself. Inferway is a custom node pack; install it as above.