MCP 3D Printer Server

scale_stl

Scale STL models uniformly or along X, Y, Z axes using scale factors. Adjust dimensions for 3D printing.

Instructions

Scale an STL model uniformly or along specific axes

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": {
      "stl_path": "<stl_path>"
    },
    "name": "scale_stl"
  }
}

Input Schema

Name	Required	Description
`scale_x`	No	X-axis scaling factor (overrides scale_factor for X axis)
`scale_y`	No	Y-axis scaling factor (overrides scale_factor for Y axis)
`scale_z`	No	Z-axis scaling factor (overrides scale_factor for Z axis)
`stl_path`	Yes	Path to the STL file
`scale_factor`	No	Uniform scaling factor to apply

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.2.9Sep 29, 2026

TDQS

B3.3/5.0

Behavior2/5

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

With no annotations, the description carries the full behavioral burden and falls short: it does not say whether the STL is scaled in place or written to a new file, whether the original is destroyed, or whether scaling is reversible. For a mutation tool with zero annotation coverage this is a meaningful gap.

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?

A single tightly written sentence with the core operation front-loaded and no filler. Every word earns its place.

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

Completeness3/5

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

Parameters are fully covered by the schema and no output schema exists, so return values need not be explained. However, for an unannotated 5-parameter mutation tool, the description should at least clarify output/destination behavior to be complete.

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

Parameters3/5

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

Schema description coverage is 100%, so the schema already documents scale_factor vs scale_x/y/z and the override behavior. The description's 'uniformly or along specific axes' adds conceptual framing but no syntax, range, or default details beyond the schema. Baseline 3 applies.

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?

States a specific verb (Scale) and resource (STL model) plus the two supported modes (uniform or per-axis). It is clearly distinguishable from siblings like rotate_stl and translate_stl, which perform different transforms on the same resource.

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

Usage Guidelines2/5

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

No indication of when to use this versus rotate_stl, translate_stl, or modify_stl_section, and no prerequisites or preconditions mentioned. The uniform-vs-per-axis distinction is really parameter semantics rather than usage guidance.

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