openscad-mcp-server

Render OpenSCAD source to a PNG image

render_scad_png

Render OpenSCAD source code into a PNG preview image. Set output size and optional camera preset or position to visualize CAD models.

Instructions

Render OpenSCAD (SCAD) source code into a PNG preview image. Provide the SCAD text in scadCode and optionally set width/height (pixels). Optional camera control is available via cameraPreset (named preset) or cameraPosition ({x,y,z}).

Input Schema

TableJSON Schema

Name	Required	Description
`width`	No	The width of the output image in pixels (default: 800)
`height`	No	The height of the output image in pixels (default: 600)
`scadCode`	Yes	The OpenSCAD code to render
`cameraPreset`	No	A named camera preset used when `cameraPosition` is not provided
`cameraPosition`	No	Camera position as { x,y,z }. Example: { x: 0, y: -25, z: 20 }

Output Schema

TableJSON Schema

Name	Required	Description	Default
`data`	Yes
`type`	Yes
`_meta`	No
`mimeType`	Yes
`annotations`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.0.6Sep 27, 2026

changedOutput schema / properties / annotations / properties / lastModified / pattern

Previous value: -"^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d(?::[0-5]\\d(?:\\.\\d+)?)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"New value: +"^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|([+-](?:[01]\\d|2[0-3]):[0-5]\\d)))$"

First observedv0.0.0Aug 11, 2026

TDQS

A3.6/5.0

Behavior3/5

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

With no annotations provided, the description carries the full behavioral burden. It discloses the required input and the preview nature of the output, but says nothing about rendering time, failure behavior on invalid SCAD, default camera semantics, or resource limits. This is adequate but leaves meaningful gaps for a compute-heavy render tool.

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?

Two tight sentences with the purpose front-loaded and the inputs enumerated immediately after. No filler or redundant restatement of the title.

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?

An output schema exists, so return values need not be explained, and all five parameters are covered with the required scadCode highlighted. The one gap is error/edge-case behavior, which the description omits entirely despite no annotations covering it.

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 every parameter, including the cameraPreset-vs-cameraPosition precedence. The description restates parameters but adds no syntax or constraint detail 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 and resource ('Render OpenSCAD (SCAD) source code into a PNG preview image'), which is unambiguous about what the tool produces. It does not name the sibling export_scad_stl, but the PNG-vs-STL distinction is implicit in the output format.

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 word 'preview' hints that this is for quick visual output rather than an export artifact, which suggests why one would pick it over export_scad_stl. However, there is no explicit when-to-use guidance, no exclusion of cases better served by the STL export sibling, and no prerequisites stated.

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

Deploy Server