Comfyui Agent Skill Mie

comfyui-agent-skill-mie

Purpose

Run registered ComfyUI workflows through a stable Agent-facing CLI, with prompt enhancement, fail-fast errors, and structured JSON results.

Use this skill when the user asks to:

• Generate an image from text.
• Generate a new image inspired by a reference image.
• Edit an input image while preserving some structure or subject details.
• Generate text-to-video or image-to-video MP4 output.
• Generate music / instrumental / song-style MP3 output.
• Synthesize spoken voice audio with Qwen3-TTS.
• Check whether a ComfyUI server is available.

Do not use this skill when the user only wants prompt writing, brainstorming, or discussion without actual generation. Do not use it when the ComfyUI server is unavailable.

Hard Rules

• Source mode: run CLI commands from the skill root (the directory containing SKILL.md and scripts/).
• Tool-install mode: comfyui-agent-skill-mie / comfyui-skill can be run from any directory.
• Source mode: use uv run --no-sync python -m comfyui (or uv run --no-sync comfyui-skill) for runtime calls.
• Tool-install mode: use comfyui-skill (or comfyui-agent-skill-mie) directly; do not wrap with uv run.
• Use registered workflows only. Do not run arbitrary unreviewed ComfyUI workflow JSON.
• If server health fails, stop generation and return/handle SERVER_UNAVAILABLE; do not search disk for ComfyUI installs or guess ports.
• Do not create or edit config.local.json unless the user explicitly wants a persistent server URL. For one-off runs, use --server or COMFYUI_URL.
• For reference_to_image, inspect the reference image with Agent vision and create a prompt. Do not upload that reference image to ComfyUI.
• For image_to_image and image_to_video, upload the provided local image with --image.
• Analyzer-generated workflow configs require human review before activation.

Workflow Selection Policy

• Built-in defaults are fallback choices, not hard requirements.
• If another registered workflow is a stronger semantic match for the request, prefer the stronger match.
• Use workflow capability metadata and workflow selection guidance to choose among registered workflows.
• Any automatic workflow selection in the CLI is only a low-risk fallback when no explicit workflow has been chosen.
• If multiple workflows appear suitable and the user’s preference is ambiguous, ask a brief clarifying question.

User-Added Workflows

• Users may add custom workflows that were first validated in ComfyUI, then imported into the skill as reviewed registered capabilities.
• Do not execute arbitrary raw workflow JSON directly.
• Import the workflow, generate/review the config template, and activate it only after a reviewed workflow.config.json exists.
• User-added workflows must be stored in the per-user workflow registry so skill upgrades do not overwrite them.
• Once activated, user-added workflows may be selected like other registered workflows when they are a stronger semantic match and required inputs are available.

Setup

Recommended install (tool-install mode):

pipx install comfyui-agent-skill-mie

• Install package: comfyui-agent-skill-mie
• Main command: comfyui-agent-skill-mie
• Short alias: comfyui-skill

Prerequisites:

• ComfyUI server with GET /system_stats available.
• Python 3.10+.
• Source mode only: uv.
• Required ComfyUI models/custom nodes for the selected workflow.

Networking note:

• Default local examples use http://127.0.0.1:8188 for same-environment setups.
• If the agent runs inside WSL/container/sandbox while ComfyUI runs on the host OS, 127.0.0.1 may refer to the runtime itself. Try --server http://localhost:8188 or the host machine IP (and optionally persist it via save-server).

Initial setup from the skill root:

uv sync
uv run --no-sync python -m comfyui --help

Tool-install mode:

comfyui-agent-skill-mie --help
comfyui-agent-skill-mie check
comfyui-skill --help
comfyui-skill check

Quick Workflow Choice

Minimal decision tree:

• User gives text only → start from general T2I (z_image_turbo fallback), but prefer a stronger registered match when workflow guidance indicates one (e.g. posters / embedded text).
• Poster / text-in-image requests → prefer qwen_image_2512_4step
• User gives a reference image and wants a new similar image → vision → reference_to_image prompt → run z_image_turbo
• User gives an input image and wants edits → generate --workflow klein_edit --image input_image=... -p "..."
• User wants TTS / voice audio → generate --workflow qwen3_tts --speech-text "..." --instruct "..."
• User wants video → ltx_23_t2v_distill (text→video) or ltx_23_i2v_distilled (image→video)

| User intent | Workflow / mode | Required command shape | |-------------|-----------------|------------------------| | Text to image (general fallback) | z_image_turbo | generate -p "prompt" | | Poster / embedded text (preferred) | qwen_image_2512_4step | generate --workflow qwen_image_2512_4step -p "prompt" | | Similar image from reference | Agent vision + T2I | Read reference image, create English prompt, then T2I | | Edit image | klein_edit | generate --workflow klein_edit --image input_image=photo.png -p "edit prompt" | | Text to video | ltx_23_t2v_distill | generate --workflow ltx_23_t2v_distill -p "shot prompt" | | Image to video | ltx_23_i2v_distilled | generate --workflow ltx_23_i2v_distilled --image input_image=photo.png -p "motion prompt" | | Text to music | ace_step_15_music | generate --workflow ace_step_15_music -p "music tags" | | Text to speech | qwen3_tts | generate --workflow qwen3_tts --speech-text "..." --instruct "..." |

For workflow-specific size rules, capability boundaries, and examples, read [references/workflows.md](references/workflows.md).

Core Commands

Environment doctor (check server + preflight registered workflows):

Tool-install mode:

comfyui-skill doctor

Source mode:

uv run --no-sync python -m comfyui doctor

If it exits with code 0, the environment is ready for all checked workflows. Exit code 1 means missing nodes/models or server is unreachable (see JSON payload).

Health check:

uv run --no-sync python -m comfyui check

Tool-install mode:

comfyui-skill check

Generate an image:

uv run --no-sync python -m comfyui generate -p "a cute cat sitting on a windowsill at golden hour"

Tool-install mode:

comfyui-skill generate -p "a cute cat sitting on a windowsill at golden hour"

Generate with a specific workflow and server:

uv run --no-sync python -m comfyui generate --workflow z_image_turbo --server http://192.168.1.100:8188 -p "a landscape"

Save a persistent server URL only when the user asks for it:

uv run --no-sync python -m comfyui save-server http://192.168.1.100:8188

Preflight a workflow before a long run:

uv run --no-sync python -m comfyui generate --workflow qwen_image_2512_4step --preflight

Show progress for long jobs:

uv run --no-sync python -m comfyui generate --workflow ltx_23_t2v_distill -p "cinematic waves at sunset, slow pan" --progress

Full CLI options, output path behavior, async submit/poll, and error code details are in [references/cli.md](references/cli.md).

Prompt Enhancement

Before generation, convert the user's intent into the right workflow inputs.

| Type | Read this file | Use when | |------|----------------|----------| | character | [references/promptenhancement/character.md](references/promptenhancement/character.md) | Portrait, person, character, figure photo | | reference_to_image | [references/promptenhancement/referencetoimage.md](references/promptenhancement/referencetoimage.md) | User provides a reference image and wants a new similar image | | image_to_image | [references/promptenhancement/imagetoimage.md](references/promptenhancement/imagetoimage.md) | User provides an input image and wants to edit it | | text_to_speech | [references/promptenhancement/texttospeech.md](references/promptenhancement/texttospeech.md) | User gives a short voice description and needs full Qwen3-TTS instruction |

Reference-to-image flow:

1. Ensure a usable reference image exists; otherwise return Agent error NO_REFERENCE_IMAGE.
2. Ensure this runtime can inspect images; otherwise return Agent error VISION_UNAVAILABLE.
3. Read the reference prompt enhancement file and create one English prompt.
4. Call T2I generation with that prompt. Do not pass the reference image to ComfyUI.

Image-to-image flow:

1. Ensure a local image path is available.
2. Read the image edit prompt enhancement file.
3. Call klein_edit with --image input_image=path.

Text-to-speech flow:

1. Split user intent into spoken content and voice/style instruction.
2. Read the TTS prompt enhancement file.
3. Call qwen3_tts with --speech-text and --instruct; do not use positional prompt.

Fail-Fast and Recovery

CLI failures are structured JSON on stdout. Agent-only pre-check failures for reference images should also be JSON.

Agent-only error shape:

{
  "source": "agent",
  "success": false,
  "error": {"code": "VISION_UNAVAILABLE", "message": "Cannot read reference image in this runtime."}
}

Required fail-fast behavior:

• Missing prompt: return/handle EMPTY_PROMPT.
• Unregistered workflow: return/handle WORKFLOW_NOT_REGISTERED.
• Server unavailable: return/handle SERVER_UNAVAILABLE and ask whether ComfyUI is running locally or on another machine.
• Missing reference image before reference_to_image: return Agent error NO_REFERENCE_IMAGE; do not call CLI.
• No vision for reference_to_image: return Agent error VISION_UNAVAILABLE; do not call CLI.
• Missing image for image workflows: return/handle NO_INPUT_IMAGE or INPUT_IMAGE_NOT_FOUND.
• Missing custom nodes/models during preflight: return/handle PREFLIGHT_MISSING_NODES or PREFLIGHT_MISSING_MODELS.

When the user provides a remote ComfyUI address, save it only if they want persistence:

uv run --no-sync python -m comfyui save-server http://:

Otherwise retry the original command with --server http://:.

Output Handling

After successful generation, present the result to the user. Do not silently parse JSON and stop.

• For images, display the file when the runtime supports local image display; otherwise provide the absolute/local path from outputs[].path.
• For MP3/MP4, provide the path or use the runtime's media display/playback capability when available.
• Prefer omitting --output; the CLI writes to a per-job directory under results/ and returns exact paths in JSON.
• For --count > 1, parse the wrapper object and present each result.

See [references/cli.md](references/cli.md) for JSON schemas and output directory rules.

References

• [references/workflows.md](references/workflows.md) — workflow selection, capabilities, size rules, examples.
• [references/cli.md](references/cli.md) — CLI contract, async jobs, output paths, JSON schemas, error codes.
• references/prompt_enhancement/ — prompt enhancement instructions.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: MieMieeeee
• Source: MieMieeeee/comfyui-agent-skill
• License: Apache-2.0

Install and usage instructions live in the source repository linked above.