Dreamer MCP

comfyui_upload_file

Upload an image, audio, or video from a URL, data URI, or base64 into ComfyUI's input folder, enabling Load* nodes to access the media for workflows.

Instructions

Upload an image/audio/video into ComfyUI's input folder, for use in Load* nodes.

Args: source: An http(s) URL, a data: URI or raw base64 content.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "source": "<source>"
    },
    "name": "comfyui_upload_file"
  }
}

Input Schema

Name	Required	Description	Default
`source`	Yes

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Sep 26, 2026

TDQS

A3.9/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It reveals the upload destination and source formats, but omits important mutating-tool details such as whether files are overwritten, how file names are derived, size limits, auth/permission needs, or how the tool actually fetches remote URLs.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two compact sentences with the key purpose front-loaded. The Args section adds necessary parameter detail without redundancy or filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter upload tool with an output schema present, the description covers the essential invocation context: what to upload, where it goes, and why it is used. The main omitted context is behavioral rather than structural, and it is already penalized in the behavioral transparency dimension.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, and the description fully compensates for the only parameter by enumerating accepted forms: http(s) URL, data URI, or raw base64 content. This is essential information the schema alone does not provide.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Description states a specific verb ('Upload'), a clear resource ('ComfyUI's input folder'), and an intended downstream use ('for use in Load* nodes'). This clearly distinguishes it from siblings that generate, view, or manage workflows.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The phrase 'for use in Load* nodes' gives some usage context, and the accepted source formats are listed. However, it never explicitly says when to choose this tool versus an alternative, nor does it mention prerequisites like 'use this before running a workflow that references the file.'

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.