BlenderMCP

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download_sketchfab_model

Download and import Sketchfab 3D models into Blender with automatic scaling to specified dimensions for scene integration.

Instructions

Download and import a Sketchfab model by its UID. The model will be scaled so its largest dimension equals target_size.

Parameters:

uid: The unique identifier of the Sketchfab model
target_size: REQUIRED. The target size in Blender units/meters for the largest dimension. You must specify the desired size for the model. Examples: - Chair: target_size=1.0 (1 meter tall) - Table: target_size=0.75 (75cm tall) - Car: target_size=4.5 (4.5 meters long) - Person: target_size=1.7 (1.7 meters tall) - Small object (cup, phone): target_size=0.1 to 0.3

Returns a message with import details including object names, dimensions, and bounding box. The model must be downloadable and you must have proper access rights.

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": {
      "uid": "<uid>",
      "target_size": "<target_size>"
    },
    "name": "download_sketchfab_model"
  }
}

Input Schema

Name	Required	Description	Default
`uid`	Yes
`target_size`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.5.5Feb 22, 2026

TDQS

A4.1/5.0

Behavior4/5

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

With no annotations, the description carries the full behavioral burden and it does a good job: it discloses the scaling behavior, the requirement to provide a target size, the return message with import details, and access prerequisites. It does not mention edge cases or failure behavior, but the core side effects are transparent.

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

Conciseness4/5

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

The description is front-loaded with purpose and scaling behavior, then provides a focused parameter list with useful examples. It is slightly repetitive about target_size being required, but no sentence feels unnecessary.

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?

The tool is simple (two parameters, no output schema), and the description covers the input semantics, the scaling behavior, prerequisites, and what the return message contains. It could add failure/edge-case behavior, but for its complexity it is reasonably complete.

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

Parameters4/5

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

Schema description coverage is 0%, but the description compensates well for target_size with units, requirement status, and concrete examples. The uid parameter is only described as 'the unique identifier,' which is thin but sufficient given the tool name and context. This is strong compensation for an otherwise bare schema.

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?

The description starts with a specific action ('Download and import a Sketchfab model by its UID') and clearly identifies the resource and key behavior. This distinguishes it from sibling Sketchfab tools like search_sketchfab_models and get_sketchfab_model_preview, which do not import.

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 description explains that the tool requires a UID and target_size and that the model must be downloadable with proper access rights, which gives some context. However, it never explicitly says when to prefer this tool over alternatives such as search_sketchfab_models or import_generated_asset, so usage guidance is only implied.

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