Outputs¶

How workflows declare their outputs, how the backend captures them, and where the files end up.

Output Declaration¶

The manifest declares what the workflow produces:

outputs:
  - id: video
    name: "Output Video"
    type: video
    node_id: "94"

Field	Required	Type	Description
`id`	Yes	string	Identifier for the output.
`name`	Yes	string	Display name shown in the UI.
`type`	Yes	string	`"video"` or `"image"`.
`node_id`	No	string	Static workflows only. The ComfyUI node ID that produces the final output.

For dynamic workflows, node_id is not needed — the assembler determines the output node from the last block's exports.

Output Types¶

`video`¶

The workflow produces a video file (typically MP4 via VHS_VideoCombine). The queue page shows a video player for preview. The history page links to the video file.

`image`¶

The workflow produces one or more images (via SaveImage). With batch_size > 1, multiple images are produced in one run. The queue shows the last preview frame. The history page shows thumbnails.

Output Directory Patching¶

Before sending any workflow (static or dynamic) to ComfyUI, the backend automatically patches all output nodes to write into the job's output directory. This ensures every generated file is organized by job.

Patching Rules¶

The backend scans every node in the assembled workflow and applies these rules:

Node Type	Original Behavior	Patched Behavior
`VHS_VideoCombine` with `save_output: true`	Saves video to ComfyUI output dir	Saves to `comfyui-studio/{jobid}/video/`
`VHS_VideoCombine` with `save_output: false`	Saves to temp (no persistent file)	Forced to `save_output: true`, saves to `comfyui-studio/{jobid}/intermediate/`
`SaveImage`	Saves to ComfyUI output dir with generic prefix	Saves to `comfyui-studio/{jobid}/image/`
`PreviewImage`	Saves to temp	Saves to `comfyui-studio/{jobid}/preview/`

Why This Matters¶

Without patching: - Videos and images scatter across ComfyUI's default output directory - Temp files are lost on restart - There's no way to associate outputs with the job that created them

With patching: - Every file lands in STUDIO_DIR/assets/output/comfyui-studio/{jobid}/ - Subfolders separate video, image, preview, and intermediate outputs - The Assets page can browse outputs by job - The History page links directly to the job's outputs - Cleanup (delete job) removes the entire directory

The `.incomplete` Marker¶

When a job starts executing, the backend creates a file called .incomplete inside the job's output directory:

assets/output/comfyui-studio/{jobid}/.incomplete

This file is removed when the job completes (success or failure). The Assets page checks for this marker and shows an .incomplete badge on directories where generation is still in progress.

Output Directory Structure¶

After a video generation job completes:

assets/output/comfyui-studio/abc123def456/
├── video/
│   └── output_00001.mp4          # Final video
├── intermediate/
│   └── intermediate_00001.mp4    # Intermediate pass (if multi-pass)
├── preview/
│   └── preview_00001.png         # Preview frame
└── image/
    └── (empty for video workflows)

After an image generation job with batch_size=4:

assets/output/comfyui-studio/abc123def456/
├── image/
│   ├── output_00001.png
│   ├── output_00002.png
│   ├── output_00003.png
│   └── output_00004.png
└── preview/
    └── preview_00001.png

Best Output Selection¶

When a job completes, the backend selects the "best" output for the job record:

Look for video files in the video/ subdirectory (not intermediate/)
If no video, look for images in the image/ subdirectory
The first found file becomes job.output (shown in history)
Multiple images are stored in job.outputs (array)

This selection is used by the History page to show a thumbnail/preview without scanning the filesystem.