ComfyUI ImageGen (Flux2)
by @halr9000
Generate images via ComfyUI API (localhost:8188) using Flux2 workflow. Supports structured JSON prompts sent directly as positive prompt parameter, seed/steps customization. Async watcher via sub-agent for low-latency, token-efficient polling (every 5s).
clawhub install comfyui-imagegenπ About This Skill
name: comfyui-imagegen description: Generate images via ComfyUI API (localhost:8188) using Flux2 workflow. Supports structured JSON prompts sent directly as positive prompt parameter, seed/steps customization. Async watcher via sub-agent for low-latency, token-efficient polling (every 5s).
ComfyUI ImageGen\n\n## Changelog\n- [2026-02-11 20:42 EST]: v1.5.0 (published) - Standalone --structured-prompt fix (no positional arg required); workflow updated to 1920x1080 16:9; production-ready with live tests (JSON direct-to-positive-prompt, async sub-agent delivery).\n- [2026-02-11 10:10 EST]: v1.4.0 - Refactored prompting: agent converts human prompt to structured JSON string; script sends JSON directly as ComfyUI positive prompt (no prose conversion). Added text-in-image quoting rule.
Changelog
--structured-prompt JSON directly (auto-generates prose internally). Removed agent-side prose step. Updated usage/examples.--submit-only (fast prompt_id return) + --watch prompt_id modes. SKILL.md docs async flow: submit β sessions_spawn watcher sub-agent (polls every 5s, auto-sends image to Telegram, ~10x token savings vs. main-agent block).message tool.darkBeastFeb0826Latest_dbkBlitzV15.safetensors. Script now polls node 84.Usage
1. Agent converts human request to mandatory structured JSON schema β compact string.
2. Verify ComfyUI runs on localhost:8188.
3. Async Mode (Recommended):
1. exec python skills/comfyui-imagegen/scripts/generate.py --structured-prompt '{"subjects":[{"description":"fluffy tabby cat","position":"center","action":"sitting relaxed"}],"scene":"cozy room interior","lighting":"warm golden sunset rays","mood":"serene and peaceful","camera":{"angle":"low angle"}}' --submit-only β parse prompt_id
2. sessions_spawn task="Set-Location 'C:\\Users\\hal\\.openclaw\\workspace'; python skills/comfyui-imagegen/scripts/generate.py --watch '{prompt_id}' --output ./gen-{prompt_id}.jpg; message action=send channel=telegram target=595846104 media=./gen-{prompt_id}.jpg; Remove-Item ./gen-{prompt_id}.jpg" label="img-{prompt_id}" cleanup=delete runTimeoutSeconds=180
/history/{prompt_id} every 5s (optimal: <5s latency, ~12 polls max @60s job, isolated tokens).
- Auto-sends JPG to this chat on completion (sub-agent pings back).
- Timeout implicitly via spawn runTimeoutSeconds=120.4. Sync Mode (blocks agent):
exec python skills/comfyui-imagegen/scripts/generate.py --structured-prompt '{"scene":"your scene"}' [--seed N] [--steps 10] [--output ./my.jpg] [--host localhost:8188]
message action=send channel=telegram media=./my.jpg
5. Customize:
| Arg | Default | Notes |
|-----|---------|-------|
| --seed | random | Repro |
| --steps | 5 | 20-50 quality |
| --host | localhost:8188 | Remote |
| --output | gen-{seed/pid}.jpg | Full path |
Structured Prompt Schema (Mandatory Format)
Agent step 1: Convert human natural language request into this exact JSON structure (all fields optional; populate only relevant; subjects array supports multiples).
Rule: For text in images (signs, logos), surround in double quotes within description/action fields, e.g., "sign reading \"STOP\"" or "logo with text \"OpenClaw\""
{
"scene": "overall scene description",
"subjects": [
{
"description": "detailed subject description",
"position": "where in frame",
"action": "what they're doing"
}
],
"style": "artistic style",
"color_palette": ["#FF0000", "#00AACC"],
"lighting": "lighting description",
"mood": "emotional tone",
"background": "background details",
"composition": "framing and layout",
"camera": {
"angle": "camera angle",
"lens": "lens type",
"depth_of_field": "focus behavior"
}
}
Agent step 2: Stringify JSON (compact, single-line for shell escaping), pass to script --structured-prompt (sent directly as ComfyUI positive prompt).
Example:
User: "A cat sitting on a windowsill at sunset"
Structured JSON string (for --structured-prompt):
'{"subjects":[{"description":"fluffy tabby cat","position":"center","action":"sitting relaxed"}],"scene":"cozy room interior","lighting":"warm golden sunset rays","mood":"serene and peaceful","camera":{"angle":"low angle"}}'
Workflow Details
darkBeastFeb0826Latest_dbkBlitzV15.safetensorsworkflows/flux2.jsonPrompting Best Practices (Flux.2 [klein] 9B)
Examples
# Async test (structured JSON string β direct positive prompt)
python .../generate.py --structured-prompt '{"subjects":[{"description":"fluffy tabby cat","position":"center","action":"sitting relaxed"}],"scene":"cozy room interior","lighting":"warm golden sunset rays","mood":"serene and peaceful","camera":{"angle":"low angle"}}' --submit-only --steps 10
β prompt_id=abc123; spawn watcher sub-agent
For cron alternative (less optimal): cron add one-shot at=now+10s payload.systemEvent="Check img job {prompt_id}" but spawn > cron for this.
π‘ Examples
# Async test (structured JSON string β direct positive prompt)
python .../generate.py --structured-prompt '{"subjects":[{"description":"fluffy tabby cat","position":"center","action":"sitting relaxed"}],"scene":"cozy room interior","lighting":"warm golden sunset rays","mood":"serene and peaceful","camera":{"angle":"low angle"}}' --submit-only --steps 10
β prompt_id=abc123; spawn watcher sub-agent
For cron alternative (less optimal): cron add one-shot at=now+10s payload.systemEvent="Check img job {prompt_id}" but spawn > cron for this.