ComfyUI Automation Skill

This skill provides a reliable, standardized workflow for interacting with ComfyUI. It is specifically designed to be easily executed by automated agents.

1. Environment Setup & Verification

ComfyUI should be installed in the primary workspace. Never install directly using root pip to avoid OS conflicts (PEP 668); always use a virtual environment (venv).

Check if installed:

ls /root/.openclaw/workspace/ComfyUI/venv/bin/activate

If missing, install:

cd /root/.openclaw/workspace
git clone https://github.com/comfyanonymous/ComfyUI.git
cd ComfyUI
python3 -m venv venv
source venv/bin/activate
pip install --upgrade pip
pip install -r requirements.txt

2. Workflow Format

ComfyUI workflows must be in API Format (a flat JSON dictionary where keys are stringified Node IDs). If the user provides a standard UI format JSON (which contains links, pos, groups arrays), kindly request the API Format or use an appropriate converter.

3. Checking and Downloading Missing Models

Workflows will fail if the required weights (UNet, Checkpoints, VAE, LoRA, CLIP) are missing from the ComfyUI/models/ subdirectories. To avoid redownloading large files, always check if the file exists first.

Use the provided script to scan the workflow JSON for model requirements and check them against the local directory:

python3 scripts/analyze_models.py /path/to/workflow_api.json /root/.openclaw/workspace/ComfyUI

Downloading: If models are missing, formulate a download script. Always use wget -nc (no clobber) or -c (continue) to prevent overwriting or duplicate downloads. Example:

cd /root/.openclaw/workspace/ComfyUI/models/checkpoints
wget -nc https://huggingface.co/path/to/model.safetensors

4. Execution via API

Do not try to run ComfyUI workflows by modifying the UI state. Instead:

1. Ensure the ComfyUI server is running locally (usually port 8188).
2. Write a lightweight Python wrapper that loads the API JSON, alters necessary parameters (like Prompts or Seeds), and posts it to the API.

Example Python Wrapper:

import json, urllib.request, random

# 1. Load the template
with open("workflow_api.json", "r") as f:
    workflow = json.load(f)

# 2. Inject user variables (Identify the correct Node IDs beforehand)
# workflow["27"]["inputs"]["text"] = "A beautiful sunset..."
# workflow["3"]["inputs"]["seed"] = random.randint(1, 9999999)

# 3. Submit to API
payload = json.dumps({"prompt": workflow}).encode('utf-8')
req = urllib.request.Request("http://127.0.0.1:8188/prompt", data=payload)
req.add_header('Content-Type', 'application/json')
res = json.loads(urllib.request.urlopen(req).read())
print(f"Prompt queued with ID: {res['prompt_id']}")

5. Error Handling & Reporting

• Missing Nodes: If the API returns an error about a missing class/node, locate the corresponding Custom Node repository, clone it into ComfyUI/custom_nodes/, and pip install -r requirements.txt inside its folder using the venv.
• OOM (Out of Memory): If the GPU runs out of VRAM, suggest adding optimization arguments like --lowvram to the ComfyUI startup command.
• Reporting: Always report the explicit failure reason to the user, including which node failed and what is missing.