MCP 3D Printer Server

extend_stl_base

Add a specified amount to the base of an STL file in inches to adjust its height for 3D printing.

Instructions

Extend the base of an STL file by a specified amount

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>",
      "extension_inches": "<extension_inches>"
    },
    "name": "extend_stl_base"
  }
}

Input Schema

Name	Required	Description	Default
`stl_path`	Yes	Path to the STL file to modify
`extension_inches`	Yes	Amount to extend the base in inches

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.2.9Sep 29, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations are supplied, so the description carries the full behavioral burden for a mutation tool. It does not say whether the file is modified in place or a new file is written, whether the original is overwritten, what happens on failure, or what the response contains — all important for a destructive file edit.

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?

A single, efficient sentence with the action and target front-loaded and zero wasted words. It is perhaps too terse given what is left unsaid, but nothing in it is redundant.

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

Completeness2/5

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

For a 2-parameter file-mutating tool with no annotations and no output schema, the description omits the essentials: in-place vs. new-file behavior, return value, and error conditions. An agent could call it but cannot predict the side effects.

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%: stl_path ("Path to the STL file to modify") and extension_inches ("Amount to extend the base in inches") are both self-documenting, including units. The description's "by a specified amount" adds nothing beyond the schema, so the baseline 3 applies.

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

Purpose4/5

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

The description gives a specific verb ("Extend") and a specific target region ("the base of an STL file"), which is clearer than the generic sibling names like modify_stl_section or translate_stl. However, it does nothing to distinguish itself from related STL-geometry siblings (scale_stl, rotate_stl, center_model, lay_flat), so an agent must infer the boundary on its own.

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?

There is no indication of when to use this rather than scale_stl, translate_stl, or modify_stl_section, no prerequisites (e.g., does the model need a flat base?), and no exclusions. The agent is left to guess how this differs from other geometry-editing tools in the list.

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