Skip to content
Get packs

Guide · Agent skill

How to use the Lab Hardware CAD agent skill

Updated · written with AI from the project's own documentation and checked against our catalogue data

Lab Hardware CAD is an agent skill that lets an AI coding agent design custom laboratory parts as parametric build123d Python models and export them as STEP, STL and DXF files. It is aimed at researchers, engineers and students who need a part that must fit existing equipment such as a microplate reader, optical table or cage system. After this guide you will know what the skill does, how to install it, how to ask for a part, and what to check before fabricating anything.

Lab Hardware CADK-Dense-AI/scientific-agent-skills · MIT

Quick start

  1. 1Download and unzip. Download the skill ZIP from this page and unzip it into ~/.claude/skills/ or a project's .claude/skills/ folder.
  2. 2Set up the environment. Create a Python 3.11 to 3.14 virtual environment and install build123d 0.13.0 and matplotlib 3.8 or later.
  3. 3Describe the part and its mating equipment. State what the part must fit, the equipment it mates with and the fabrication process.
  4. 4Provide interface dimensions. Supply vendor drawings or measurements for any interface not in the bundled standards.
  5. 5Review the model and renders. Check the generated STEP, STL or DXF output and the visual renders before fabricating.
  6. 6Fabricate after verification. Print, cut or machine only after a test coupon confirms the tolerances for your process.

What is an agent skill, and what does this one make the agent do?

An agent skill is a folder of instructions, reference files and scripts that an AI agent loads when a task matches its description. This skill covers physical research hardware: microfluidic chips and molds, optomechanical mounts and breadboard adapters, cuvette and microplate holders, tube racks, animal-behavior rig parts and 3D-printed instrument fixtures.

The agent writes each design as parametric Python code using build123d, checks key dimensions against bundled standards such as SLAS microplate footprints and optical breadboard hole grids, and exports STEP, STL and DXF files. The skill also requires a visual review of renders before a part is considered done.

  • Designs are source code, so you can change a dimension and regenerate the part.
  • STEP is the authoritative export; the source file is the design of record.
  • It does not cover finite-element analysis, CFD, molecular structure or scientific plotting.

Install the lab-hardware-cad skill

Download the ZIP for this skill from this page. Then either unzip it into your personal skills folder, ~/.claude/skills/, or into a project's .claude/skills/ folder so it applies only to that project.

If you use the Claude apps instead, upload the ZIP under Settings, then Capabilities, then Skills.

  • Personal install: unzip into ~/.claude/skills/.
  • Project install: unzip into .claude/skills/ inside your project.
  • Claude apps: Settings → Capabilities → Skills, then upload the ZIP.

Set up the Python environment for build123d

The geometry needs build123d 0.13.0 on Python 3.11 to 3.14. The skill's setup uses uv to create a virtual environment and install build123d and matplotlib. The OpenCascade kernel comes in through cadquery-ocp-novtk, and the download is large, so install it once per project and reuse it.

Standards lookups and the interface check run on the standard library alone, so you can test those before installing build123d.

  • Python 3.11 to 3.14 is required.
  • matplotlib 3.8 or later is needed for snapshots.
  • Network access is needed for installation and for fetching current vendor drawings. Local geometry checks run offline.
uv venv --python 3.12 .venv-labcad uv pip install --python .venv-labcad/bin/python "build123d==0.13.0" "matplotlib>=3.8"

How do you trigger the skill with a natural request?

You do not need special syntax. Describe the physical part, the equipment it must mate with and the process you plan to use. The skill is meant to load when a request involves a part that must fit standardized labware, an optical table, a cage system, or a printer, CNC or laser process.

The agent should then state which device family it routed to, list each mating interface with its source, and ask you for a vendor drawing or measurement if a dimension is not in its standards file.

  • Name the equipment: "a holder for a 96-well SLAS plate in a plate reader".
  • Name the process: "3D printed in FDM" or "laser-cut acrylic".
  • Name the output you need: STEP for CAD work, STL for printing, DXF for laser or CNC.

Examples of requests and what to expect

A good request names the interface. For example, asking for a cuvette holder that fits a 10 mm standard cuvette lets the agent use the bundled cuvette-standard-10mm dimensions. An optical mount for a 25 mm grid breadboard can use the optical-breadboard-metric standard.

If your part mates with nothing in the bundled list, the agent should say so and mark those interface dimensions as unchecked rather than guessing. For animal-behavior rigs, the agent will ask which protocol or paper the rig replicates, because those dimensions are not standardized.

  • "Make a 96-well plate holder that sits in a microplate reader; export STEP and STL."
  • "Design an M3-style post adapter for a 25 mm optical breadboard and export DXF for laser cutting."
  • "Model a microfluidic chip with two inlet ports and a mold for it; FDM is not acceptable for cell contact."
  • "Create a tube rack for 15 mL tubes in a 3D printed fixture."

Safety notes: scripts run and the network is used

The model files are executed, not parsed. The scripts import a *_model.py file and call its build() function, which runs arbitrary Python in your environment. Only run model files written in the current session or supplied by you from a trusted location. If a model came from the internet, a shared drive or an untrusted colleague, read it first and tell the agent you did.

The skill uses the network for installation and for fetching current vendor drawings. Local geometry checks run offline. Parts intended for cell contact or load-bearing use need validated materials and assay testing, which the skill itself flags as required.

  • Read untrusted model files before running them.
  • Process and material validation is your responsibility for any part that contacts cells or carries load.
  • Dimensions not in the bundled standards remain unchecked and your responsibility to verify against vendor drawings.

Tips for better results

Give the agent the vendor drawing or measurement for every interface you care about. The skill is designed to ask for these instead of guessing, so supplying them early saves a round trip.

Choose the fabrication process before the geometry, because process sets minimum wall thickness, achievable tolerance and whether a part survives autoclaving or your solvent. Verify tolerances with a test coupon, since the planning figures depend on your machine and material.

  • Provide vendor drawings or measured values up front.
  • State the process and material in your request.
  • Expect a visual review of renders before the part is called finished.
  • For animal rigs, name the protocol or paper being replicated.

What people use it for

  • Holding a 96-well plate steady in a microplate reader with dimensions checked against the SLAS footprint.
  • Making a breadboard adapter that bolts to an optical table hole grid.
  • Designing a microfluidic chip and matching mold for a bonding process.
  • Printing a tube rack for common tube sizes as a 3D printed fixture.
  • Producing DXF outlines of a mount for laser cutting.

Frequently asked questions

How do I install the lab-hardware-cad skill?

Download the ZIP from this page and unzip it into ~/.claude/skills/ for personal use or into a project's .claude/skills/ folder. In the Claude apps, upload the ZIP under Settings, then Capabilities, then Skills.

What are the requirements for lab-hardware-cad?

You need Python 3.11 to 3.14, build123d 0.13.0 with its OpenCascade kernel, and matplotlib 3.8 or later for snapshots. Network access is needed for installation and for fetching vendor drawings, while local geometry checks run offline.

Is the lab-hardware-cad skill free?

The skill is published under the MIT licence. The source does not state pricing for other parts of the setup, so check the licence file in the repository for the terms that apply.

Does it run scripts and use the network?

Yes on both counts. The bundled scripts import and execute your model files, and the network is used for installation and vendor drawings, so only run models from trusted sources.

What can I use instead of this skill?

The skill does not cover finite-element analysis, CFD, molecular structure or scientific plotting, so use dedicated tools for those. For general CAD without its standards checks, you would need to verify interface dimensions against vendor drawings yourself.

Why does the agent ask for a vendor drawing?

The skill never writes interface dimensions from memory. If a dimension is not in its standards file or reference, it asks for the vendor drawing or measurement so the part is not built on a guessed number.

New agent skills, repos and AI tools — every week

The best new skills and open-source projects, the fastest-growing repos, and one free prompt. Five minutes to read. Unsubscribe anytime.

Our verdict

Use this skill if you need a custom lab part that must fit a microplate reader, optical table, cage system or a printer or laser process, and you want dimensions checked against bundled standards. Pick something else if you need simulation, plotting or molecular work, or if your part contacts cells or carries load and you cannot run material and assay validation.

Download the skill