mckruz/comfyui-expert/comfyui-workflow-builder

ComfyUI Workflow Builder

Translates natural language requests into executable ComfyUI workflow JSON. Always validates against inventory before generating.

Workflow Generation Process

Step 1: Understand the Request

Parse the user's intent into:

• Output type: Image, video, or audio
• Source material: Text-only, reference image(s), existing video
• Identity method: None, zero-shot (InstantID/PuLID), LoRA, Kontext
• Quality level: Draft (fast iteration) vs production (maximum quality)
• Special requirements: ControlNet, inpainting, upscaling, lip-sync

Step 2: Check Inventory

Read state/inventory.json to determine:

• Available checkpoints → select best match for task
• Available identity models → determine which methods are possible
• Available ControlNet models → enable pose/depth control if available
• Custom nodes installed → verify all required nodes exist
• VRAM available → optimize settings accordingly

Step 3: Select Pipeline Pattern

Based on request + inventory, choose from:

Step 4: Generate Workflow JSON

ComfyUI workflow format:

{
  "{node_id}": {
    "class_type": "{NodeClassName}",
    "inputs": {
      "{param_name}": "{value}",
      "{connected_param}": ["{source_node_id}", {output_index}]
    }
  }
}

Rules:

• Node IDs are strings (typically "1", "2", "3"...)
• Connected inputs use array format: ["source_node_id", output_index]
• Output index is 0-based integer
• Filenames must match exactly what's in inventory
• Seed values: use random large integer or fixed for reproducibility

Step 5: Validate

Before presenting to user:

1. Every class_type exists in inventory's node list
2. Every model filename exists in inventory's model list
3. All required connections are present (no dangling inputs)
4. VRAM estimate doesn't exceed available VRAM
5. Resolution is compatible with chosen model (512 for SD1.5, 1024 for SDXL/FLUX)

Step 6: Output

If online mode: Queue via comfyui-api skill If offline mode: Save JSON to projects/{project}/workflows/ with descriptive name

Workflow Templates

Basic Text-to-Image (FLUX)

{
  "1": {
    "class_type": "LoadCheckpoint",
    "inputs": {"ckpt_name": "flux1-dev.safetensors"}
  },
  "2": {
    "class_type": "CLIPTextEncode",
    "inputs": {"text": "{positive_prompt}", "clip": ["1", 1]}
  },
  "3": {
    "class_type": "CLIPTextEncode",
    "inputs": {"text": "{negative_prompt}", "clip": ["1", 1]}
  },
  "4": {
    "class_type": "EmptyLatentImage",
    "inputs": {"width": 1024, "height": 1024, "batch_size": 1}
  },
  "5": {
    "class_type": "KSampler",
    "inputs": {
      "seed": 42,
      "steps": 25,
      "cfg": 3.5,
      "sampler_name": "euler",
      "scheduler": "normal",
      "denoise": 1.0,
      "model": ["1", 0],
      "positive": ["2", 0],
      "negative": ["3", 0],
      "latent_image": ["4", 0]
    }
  },
  "6": {
    "class_type": "VAEDecode",
    "inputs": {"samples": ["5", 0], "vae": ["1", 2]}
  },
  "7": {
    "class_type": "SaveImage",
    "inputs": {"filename_prefix": "output", "images": ["6", 0]}
  }
}

With Identity Preservation (InstantID + IP-Adapter)

Extends basic template by adding:

• Load reference image node
• InstantID Model Loader + Apply InstantID
• IPAdapter Unified Loader + Apply IPAdapter
• FaceDetailer post-processing

See references/workflows.md for complete node settings.

Video Generation (Wan I2V)

Uses different loader chain:

• Load Diffusion Model (not LoadCheckpoint)
• Wan I2V Conditioning
• EmptySD3LatentImage (with frame count)
• Video Combine (VHS)

See references/workflows.md Workflow 4 for complete settings.

VRAM Estimation

Common Mistakes to Avoid

1. Wrong output index: CheckpointLoader outputs [model, clip, vae] at indices [0, 1, 2]
2. CFG too high for InstantID: Use 4-5, not default 7-8
3. Wrong resolution for model: FLUX/SDXL=1024, SD1.5=512
4. Missing VAE: FLUX needs explicit VAE (ae.safetensors)
5. Wrong model in wrong loader: Diffusion models need LoadDiffusionModel, not LoadCheckpoint

Reference Files

• references/workflows.md - Detailed node-by-node templates
• references/models.md - Model files and paths
• references/prompt-templates.md - Model-specific prompts
• state/inventory.json - Current inventory cache