ComfyUI Skill for Hermes Agent: Setup, Workflows, and Execution

The ComfyUI skill equips Hermes Agent with the ability to generate images, video, audio, and 3D content through ComfyUI diffusion workflows. It uses the official comfy-cli for setup and lifecycle management, and direct REST/WebSocket API calls for workflow execution. This guide covers everything from hardware checks and installation to running complex batch jobs and troubleshooting common pitfalls.

What it does

This skill turns Hermes Agent into a generative media powerhouse. It can:

Generate images with Stable Diffusion, SDXL, Flux, SD3, and other models.
Run specific ComfyUI workflow files provided by the user or from the skill's own library.
Chain generative steps like text-to-image, upscaling, and face restoration in a single pipeline.
Handle advanced pipelines including ControlNet, inpainting, and img2img.
Manage the ComfyUI queue, check installed models, and install custom nodes.
Generate video and audio via AnimateDiff, Hunyuan, Wan, AudioCraft, and similar tools.

The skill is bundled with Hermes Agent (installed by default) and is available on macOS, Linux, and Windows.

Before you start

Before using this skill, you need a working ComfyUI environment. The skill provides two layers for this:

┌─────────────────────────────────────────────────────┐
│ Layer 1: comfy-cli (official lifecycle tool)        │
│   Setup, server lifecycle, custom nodes, models     │
│   → comfy install / launch / stop / node / model    │
└─────────────────────────┬───────────────────────────┘
                          │
┌─────────────────────────▼───────────────────────────┐
│ Layer 2: REST/WebSocket API + skill scripts         │
│   Workflow execution, param injection, monitoring   │
│   POST /api/prompt, GET /api/view, WS /ws           │
│   → run_workflow.py, run_batch.py, ws_monitor.py    │
└─────────────────────────────────────────────────────┘

The official CLI is excellent for installation and server management but has minimal workflow execution support. The REST/WS API fills that gap, the scripts handle parameter injection, execution monitoring, and output download that the CLI doesn't do.

Detect your environment

First, check what's already available:

# What's available?
command -v comfy >/dev/null 2>&1 && echo "comfy-cli: installed"
curl -s http://127.0.0.1:8188/system_stats 2>/dev/null && echo "server: running"

# Can this machine run ComfyUI locally? (GPU/VRAM/disk check)
python3 scripts/hardware_check.py

If nothing is installed, see Setup & Onboarding below, but always run the hardware check first.

One-line health check

python3 scripts/health_check.py
# → JSON: comfy_cli on PATH? server reachable? at least one checkpoint? smoke-test passes?

Core Workflow

Step 1: Get a workflow JSON in API format

Workflows must be in API format (each node has class_type). They come from:

ComfyUI web UI → Workflow → Export (API) (newer UI) or the legacy "Save (API Format)" button (older UI)
This skill's workflows/ directory (ready-to-run examples)
Community downloads (civitai, Reddit, Discord), usually editor format, must be loaded into ComfyUI then re-exported

Editor format (top-level nodes and links arrays) is not directly executable. The scripts detect this and tell you to re-export.

Step 2: See what's controllable

python3 scripts/extract_schema.py workflow_api.json --summary-only
# → {"parameter_count": 12, "has_negative_prompt": true, "has_seed": true, ...}

python3 scripts/extract_schema.py workflow_api.json
# → full schema with parameters, model deps, embedding refs

Step 3: Run with parameters

# Local (defaults to http://127.0.0.1:8188)
python3 scripts/run_workflow.py \
  --workflow workflow_api.json \
  --args '{"prompt": "a beautiful sunset over mountains", "seed": -1, "steps": 30}' \
  --output-dir ./outputs

# Cloud (export API key once; uses correct /api routing automatically)
export COMFY_CLOUD_API_KEY="comfyui-..."
python3 scripts/run_workflow.py \
  --workflow workflow_api.json \
  --args '{"prompt": "..."}' \
  --host https://cloud.comfy.org \
  --output-dir ./outputs

# Real-time progress via WebSocket (requires `pip install websocket-client`)
python3 scripts/run_workflow.py \
  --workflow flux_dev.json \
  --args '{"prompt": "..."}' \
  --ws

# img2img / inpaint: pass --input-image to upload + reference automatically
python3 scripts/run_workflow.py \
  --workflow sdxl_img2img.json \
  --input-image image=./photo.png \
  --args '{"prompt": "make it watercolor", "denoise": 0.6}'

# Batch / sweep: 8 random seeds, parallel up to cloud tier limit
python3 scripts/run_batch.py \
  --workflow sdxl.json \
  --args '{"prompt": "abstract"}' \
  --count 8 --randomize-seed --parallel 3 \
  --output-dir ./outputs/batch

-1 for seed (or omitting it with --randomize-seed) generates a fresh random seed per run.

Step 4: Present results

The scripts emit JSON to stdout describing every output file:

{
  "status": "success",
  "prompt_id": "abc-123",
  "outputs": [
    {"file": "./outputs/sdxl_00001_.png", "node_id": "9",
     "type": "image", "filename": "sdxl_00001_.png"}
  ]
}

Decision Tree

User says	Tool	Command
Lifecycle (use comfy-cli)
"install ComfyUI"	comfy-cli	`bash scripts/comfyui_setup.sh`
"start ComfyUI"	comfy-cli	`comfy launch --background`
"stop ComfyUI"	comfy-cli	`comfy stop`
"install X node"	comfy-cli	`comfy node install`
"download X model"	comfy-cli	`comfy model download --url --relative-path models/checkpoints`
"list installed models"	comfy-cli	`comfy model list`
"list installed nodes"	comfy-cli	`comfy node show installed`
Execution (use scripts)
"is everything ready?"	script	`health_check.py` (optionally with `--workflow X --smoke-test`)
"what can I change in this workflow?"	script	`extract_schema.py W.json`
"check if W's deps are met"	script	`check_deps.py W.json`
"fix missing deps"	script	`auto_fix_deps.py W.json`
"generate an image"	script	`run_workflow.py --workflow W --args '{...}'`
"use this image" (img2img)	script	`run_workflow.py --input-image image=./x.png ...`
"8 variations with random seeds"	script	`run_batch.py --count 8 --randomize-seed ...`
"show me live progress"	script	`ws_monitor.py --prompt-id`
"fetch the error from job X"	script	`fetch_logs.py`
Direct REST
"what's in the queue?"	REST	`curl http://HOST:8188/queue` (local) or `--host https://cloud.comfy.org`
"cancel that"	REST	`curl -X POST http://HOST:8188/interrupt`
"free GPU memory"	REST	`curl -X POST http://HOST:8188/free`

Setup & Onboarding

When a user asks to set up ComfyUI, the FIRST thing to do is ask whether they want Comfy Cloud (hosted, zero install, API key) or Local (install ComfyUI on their machine). Don't start running install commands or hardware checks until they've answered.

Official docs: https://docs.comfy.org/installation CLI docs: https://docs.comfy.org/comfy-cli/getting-started Cloud docs: https://docs.comfy.org/get_started/cloud Cloud API: https://docs.comfy.org/development/cloud/overview

Step 0: Ask Local vs Cloud (ALWAYS FIRST)

Suggested script:

"Do you want to run ComfyUI locally on your machine, or use Comfy Cloud?

Comfy Cloud, hosted on RTX 6000 Pro GPUs, all common models pre-installed, zero setup. Requires an API key (paid subscription required to actually run workflows; free tier is read-only). Best if you don't have a capable GPU.

Local, free, but your machine MUST meet the hardware requirements:

NVIDIA GPU with ≥6 GB VRAM (≥8 GB for SDXL, ≥12 GB for Flux/video), OR

AMD GPU with ROCm support (Linux), OR

Apple Silicon Mac (M1+) with ≥16 GB unified memory (≥32 GB recommended).

Intel Macs and machines with no GPU will NOT work, use Cloud instead.

Which would you like?"

Routing:

Cloud → skip to Path A.
Local → run hardware check first, then pick a path from Paths B, E based on the verdict.
Unsure → run the hardware check and let the verdict decide.

Step 1: Verify Hardware (ONLY if user chose local)

python3 scripts/hardware_check.py --json
# Optional: also probe `torch` for actual CUDA/MPS:
python3 scripts/hardware_check.py --json --check-pytorch

Verdict	Meaning	Action
`ok`	≥8 GB VRAM (discrete) OR ≥32 GB unified (Apple Silicon)	Local install, use `comfy_cli_flag` from report
`marginal`	SD1.5 works; SDXL tight; Flux/video unlikely	Local OK for light workflows, else Path A (Cloud)
`cloud`	No usable GPU, <6 GB VRAM, <16 GB Apple unified, Intel Mac, Rosetta Python	Switch to Cloud unless user explicitly forces local

The script also surfaces wsl: true (WSL2 with NVIDIA passthrough) and rosetta: true (x86_64 Python on Apple Silicon, must reinstall as ARM64).

If verdict is cloud but the user wants local, do not proceed silently. Show the notes array verbatim and ask whether they want to (a) switch to Cloud or (b) force a local install (will OOM or be unusably slow on modern models).

Choosing an Installation Path

Use the hardware check first. The table below is the fallback for when the user has already told you their hardware:

Situation	Recommended Path
`verdict: cloud` from hardware check	Path A: Comfy Cloud
No GPU / want to try without commitment	Path A: Comfy Cloud
Windows + NVIDIA + non-technical	Path B: ComfyUI Desktop
Windows + NVIDIA + technical	Path C: Portable or Path D: comfy-cli
Linux + any GPU	Path D: comfy-cli (easiest)
macOS + Apple Silicon	Path B: Desktop or Path D: comfy-cli
Headless / server / CI / agents	Path D: comfy-cli

For the fully automated path (hardware check → install → launch → verify):

bash scripts/comfyui_setup.sh
# Or with overrides:
bash scripts/comfyui_setup.sh --m-series --port=8190 --workspace=/data/comfy

It runs hardware_check.py internally, refuses to install locally when the verdict is cloud (unless --force-cloud-override), picks the right comfy-cli flag, and prefers pipx/uvx over global pip to avoid polluting system Python.

Path A: Comfy Cloud (No Local Install)

For users without a capable GPU or who want zero setup. Hosted on RTX 6000 Pro.

Docs: https://docs.comfy.org/get_started/cloud

Sign up at https://comfy.org/cloud
Generate an API key at https://platform.comfy.org/login
Set the key:

export COMFY_CLOUD_API_KEY="comfyui-xxxxxxxxxxxx"

Run workflows:

python3 scripts/run_workflow.py \
  --workflow workflows/flux_dev_txt2img.json \
  --args '{"prompt": "..."}' \
  --host https://cloud.comfy.org \
  --output-dir ./outputs

Pricing: https://www.comfy.org/cloud/pricing Concurrent jobs: Free/Standard 1, Creator 3, Pro 5. Free tier cannot run workflows via API, only browse models. Paid subscription required for /api/prompt, /api/upload/*, /api/view, etc.

Path B: ComfyUI Desktop (Windows / macOS)

One-click installer for non-technical users. Currently Beta.

Docs: https://docs.comfy.org/installation/desktop

Windows (NVIDIA): https://download.comfy.org/windows/nsis/x64
macOS (Apple Silicon): https://comfy.org

Linux is not supported for Desktop, use Path D.

Path C: ComfyUI Portable (Windows Only)

Docs: https://docs.comfy.org/installation/comfyui_portable_windows

Download from https://github.com/comfyanonymous/ComfyUI/releases, extract, run run_nvidia_gpu.bat. Update via update/update_comfyui_stable.bat.

Path D: comfy-cli (All Platforms, Recommended for Agents)

The official CLI is the best path for headless/automated setups.

Docs: https://docs.comfy.org/comfy-cli/getting-started

Install comfy-cli

# Recommended:
pipx install comfy-cli
# Or use uvx without installing:
uvx --from comfy-cli comfy --help
# Or (if pipx/uvx unavailable):
pip install --user comfy-cli

Disable analytics non-interactively:

comfy --skip-prompt tracking disable

Install ComfyUI

comfy --skip-prompt install --nvidia              # NVIDIA (CUDA)
comfy --skip-prompt install --amd                 # AMD (ROCm, Linux)
comfy --skip-prompt install --m-series            # Apple Silicon (MPS)
comfy --skip-prompt install --cpu                 # CPU only (slow)
comfy --skip-prompt install --nvidia --fast-deps  # uv-based dep resolution

Default location: ~/comfy/ComfyUI (Linux), ~/Documents/comfy/ComfyUI (macOS/Win). Override with comfy --workspace /custom/path install.

Launch / verify

comfy launch --background                       # background daemon on :8188
comfy launch -- --listen 0.0.0.0 --port 8190    # LAN-accessible custom port
curl -s http://127.0.0.1:8188/system_stats      # health check

Path E: Manual Install (Advanced / Unsupported Hardware)

For Ascend NPU, Cambricon MLU, Intel Arc, or other unsupported hardware.

Docs: https://docs.comfy.org/installation/manual_install

git clone https://github.com/comfyanonymous/ComfyUI.git
cd ComfyUI
pip install torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/cu130
pip install -r requirements.txt
python main.py

Post-Install: Download Models

# SDXL (general purpose, ~6.5 GB)
comfy model download \
  --url "https://huggingface.co/stabilityai/stable-diffusion-xl-base-1.0/resolve/main/sd_xl_base_1.0.safetensors" \
  --relative-path models/checkpoints

# SD 1.5 (lighter, ~4 GB, good for 6 GB cards)
comfy model download \
  --url "https://huggingface.co/stable-diffusion-v1-5/stable-diffusion-v1-5/resolve/main/v1-5-pruned-emaonly.safetensors" \
  --relative-path models/checkpoints

# Flux Dev fp8 (smaller variant, ~12 GB)
comfy model download \
  --url "https://huggingface.co/Comfy-Org/flux1-dev/resolve/main/flux1-dev-fp8.safetensors" \
  --relative-path models/checkpoints

# CivitAI (set token first):
comfy model download \
  --url "https://civitai.com/api/download/models/128713" \
  --relative-path models/checkpoints \
  --set-civitai-api-token "YOUR_TOKEN"

List installed: comfy model list.

Post-Install: Install Custom Nodes

comfy node install comfyui-impact-pack             # popular utility pack
comfy node install comfyui-animatediff-evolved     # video generation
comfy node install comfyui-controlnet-aux          # ControlNet preprocessors
comfy node install comfyui-essentials              # common helpers
comfy node update all
comfy node install-deps --workflow=workflow.json   # install everything a workflow needs

Post-Install: Verify

python3 scripts/health_check.py
# → comfy_cli on PATH? server reachable? checkpoints? smoke test?

python3 scripts/check_deps.py my_workflow.json
# → are this workflow's nodes/models/embeddings installed?

python3 scripts/run_workflow.py \
  --workflow workflows/sd15_txt2img.json \
  --args '{"prompt": "test", "steps": 4}' \
  --output-dir ./test-outputs

Image Upload (img2img / Inpainting)

The simplest way is to use --input-image with run_workflow.py:

python3 scripts/run_workflow.py \
  --workflow workflows/sdxl_img2img.json \
  --input-image image=./photo.png \
  --args '{"prompt": "make it cyberpunk", "denoise": 0.6}'

The flag uploads photo.png, then injects its server-side filename into whatever schema parameter is named image. For inpainting, pass both:

python3 scripts/run_workflow.py \
  --workflow workflows/sdxl_inpaint.json \
  --input-image image=./photo.png \
  --input-image mask_image=./mask.png \
  --args '{"prompt": "fill with flowers"}'

Manual upload via REST:

curl -X POST "http://127.0.0.1:8188/upload/image" \
  -F "image=@photo.png" -F "type=input" -F "overwrite=true"
# Returns: {"name": "photo.png", "subfolder": "", "type": "input"}

# Cloud equivalent:
curl -X POST "https://cloud.comfy.org/api/upload/image" \
  -H "X-API-Key: $COMFY_CLOUD_API_KEY" \
  -F "image=@photo.png" -F "type=input" -F "overwrite=true"

Cloud Specifics

Base URL: https://cloud.comfy.org
Auth: X-API-Key header (or ?token=KEY for WebSocket)
API key: set $COMFY_CLOUD_API_KEY once and the scripts pick it up automatically
Output download: /api/view returns a 302 to a signed URL; the scripts follow it and strip X-API-Key before fetching from the storage backend (don't leak the API key to S3/CloudFront).
Endpoint differences from local ComfyUI:
- /api/object_info, /api/queue, /api/userdata, 403 on free tier; paid only.
- /history is renamed to /history_v2 on cloud (the scripts route automatically).
- /models/ is renamed to /experiment/models/ on cloud (the scripts route automatically).
- clientId in WebSocket is currently ignored, all connections for a user receive the same broadcast. Filter by prompt_id client-side.
- subfolder is accepted on uploads but ignored, cloud has a flat namespace.
Concurrent jobs: Free/Standard: 1, Creator: 3, Pro: 5. Extras queue automatically. Use run_batch.py --parallel N to saturate your tier.

Queue & System Management

# Local
curl -s http://127.0.0.1:8188/queue | python3 -m json.tool
curl -X POST http://127.0.0.1:8188/queue -d '{"clear": true}'    # cancel pending
curl -X POST http://127.0.0.1:8188/interrupt                      # cancel running
curl -X POST http://127.0.0.1:8188/free \
  -H "Content-Type: application/json" \
  -d '{"unload_models": true, "free_memory": true}'

# Cloud — same paths under /api/, plus:
python3 scripts/fetch_logs.py --tail-queue --host https://cloud.comfy.org

Pitfalls

API format required, every script and the /api/prompt endpoint expect API-format workflow JSON. The scripts detect editor format (top-level nodes and links arrays) and tell you to re-export via "Workflow → Export (API)" (newer UI) or "Save (API Format)" (older UI).
Server must be running, all execution requires a live server. comfy launch --background starts one. Verify with curl http://127.0.0.1:8188/system_stats.
Model names are exact, case-sensitive, includes file extension. check_deps.py does fuzzy matching (with/without extension and folder prefix), but the workflow itself must use the canonical name. Use comfy model list to discover what's installed.
Missing custom nodes, "class_type not found" means a required node isn't installed. check_deps.py reports which package to install; auto_fix_deps.py runs the install for you.
Working directory, comfy-cli auto-detects the ComfyUI workspace. If commands fail with "no workspace found", use comfy --workspace /path/to/ComfyUI or comfy set-default /path/to/ComfyUI.
Cloud free-tier API limits, /api/prompt, /api/view, /api/upload/*, /api/object_info all return 403 on free accounts. health_check.py and check_deps.py handle this gracefully and surface a clear message.
Timeout for video/audio workflows, auto-detected when an output node is VHS_VideoCombine, SaveVideo, etc.; the default jumps from 300 s to 900 s. Override explicitly with --timeout 1800.
Path traversal in output filenames, server-supplied filenames are passed through safe_path_join to refuse anything escaping --output-dir. Keep this protection on, workflows with custom save nodes can produce arbitrary paths.
Workflow JSON is arbitrary code, custom nodes run Python, so submitting an unknown workflow has the same trust profile as eval. Inspect workflows from untrusted sources before running.
Auto-randomized seed, pass seed: -1 in --args (or use --randomize-seed and omit the seed) to get a fresh seed per run. The actual seed is logged to stderr.
tracking prompt, first run of comfy may prompt for analytics. Use comfy --skip-prompt tracking disable to skip non-interactively. comfyui_setup.sh does this for you.

Verification Checklist

Use python3 scripts/health_check.py to run the whole list at once. Manual:

hardware_check.py verdict is ok OR the user explicitly chose Comfy Cloud
comfy --version works (or uvx --from comfy-cli comfy --help)
curl http://HOST:PORT/system_stats returns JSON
comfy model list shows at least one checkpoint (local) OR /api/experiment/models/checkpoints returns models (cloud)
Workflow JSON is in API format
check_deps.py reports is_ready: true (or only node_check_skipped on cloud free tier)
Test run with a small workflow completes; outputs land in --output-dir

When not to use it

This skill is not the right choice if the user only needs a simple text-to-image generation without any workflow customization. For that, the related stable-diffusion-image-generation skill provides a more streamlined interface. Also, if the user's hardware cannot meet the minimum requirements and they are unwilling to use Comfy Cloud, this skill will not function.

Limits and gotchas

Free tier Comfy Cloud cannot execute workflows via the API. A paid subscription is required for any actual generation.
Concurrent job limits on Comfy Cloud vary by subscription tier (Free/Standard: 1, Creator: 3, Pro: 5).
Video/audio workflows have a longer default timeout (900 seconds) but may still fail for very long generations.
Workflow JSON from untrusted sources is effectively arbitrary code execution. Always inspect before running.
Path traversal protection is built into the output handling, but custom save nodes can still produce unexpected filenames.

What pairs with this

The related skill stable-diffusion-image-generation offers a simpler, non-workflow-based interface for basic image generation. For more complex pipelines, this ComfyUI skill is the appropriate choice.

ComfyUI Skill for Hermes Agent: Image, Video & Audio Generation