mcmaster-catalog

name	mcmaster-catalog
description	Build a structured McMaster-Carr product catalog (JSON + CSV) from a manually collected parts list. Records part number, name, URL, STEP file status, USD conversion status, category, and specs. McMaster requires login and blocks all automated clients, so part numbers must be collected manually.

McMaster-Carr Product Catalog Skill

Use this skill when the user asks to catalog, organize, or track McMaster-Carr products — especially for managing downloaded STEP files and USD conversions.

Why manual input is required

McMaster-Carr requires a logged-in account for all product browsing and actively blocks all automated HTTP clients (requests, headless browsers, Playwright, Selenium). This is confirmed and cannot be bypassed without violating their Terms of Service.

Workflow

Step 1 — Browse www.mcmaster.com (logged in) and collect part numbers
Step 2 — Save them to a .txt or .csv file
Step 3 — python mcmaster_catalog.py parts.txt --tag <label>
Step 4 — Download STEP files manually from each product URL (browser)
Step 5 — python mcmaster_to_usd.py --part <PART> --file ~/Downloads/<FILE>.step

Step 1 — Creating the parts file

Plain text (simplest — one part number per line):

1718K33
7014N106
5972K394

CSV (richer — with optional name, url, category, notes):

part_number,name,url,category,notes
7014N106,Base-Mount AC Motor,https://www.mcmaster.com/7014N106/,Motors,60Hz
1718K33,Fan Blade,,Fans,
5972K394,Ball Bearing,,Bearings,10mm bore

Step 3 — Running the catalog builder

python mcmaster_catalog.py parts.txt
python mcmaster_catalog.py parts.txt  --tag motors     --step-dir ~/Downloads
python mcmaster_catalog.py parts.csv  --tag bearings   --out output/bearings
python mcmaster_catalog.py parts.txt  --verbose

Flags

Flag	Meaning
--tag LABEL	Label for output filenames (default: catalog)
--step-dir DIR	Directory with downloaded STEP files (auto-matched by part number)
--out DIR	Output directory (default: output/mcmaster_catalog/)
--verbose	Debug logging

Output files

output/mcmaster_catalog/mcmaster_<tag>_<timestamp>.json
output/mcmaster_catalog/mcmaster_<tag>_<timestamp>.csv

JSON structure

{
  "tag": "motors",
  "generated_at": "2026-03-25T10:00:00Z",
  "total": 5,
  "step_available": 3,
  "usd_converted": 1,
  "products": [
    {
      "part_number": "7014N106",
      "name": "Base-Mount AC Motor",
      "url": "https://www.mcmaster.com/7014N106/",
      "has_cad": true,
      "step_file": "output/7014N106/7014N106.step",
      "usd_file": "output/7014N106/7014N106.usd",
      "category": "Motors",
      "notes": "60Hz",
      "specs": {}
    }
  ]
}

CSV columns

part_number, name, url, has_cad, step_file, usd_file, category, notes, specs

Full pipeline example

# 1. After browsing McMaster manually, create parts.txt:
echo "7014N106" > parts.txt
echo "1718K33"  >> parts.txt

# 2. Build the catalog (cross-references any downloaded STEP files)
python mcmaster_catalog.py parts.txt --tag my_parts --step-dir ~/Downloads

# 3. Convert each downloaded STEP to USD
python mcmaster_to_usd.py --part 7014N106 --file ~/Downloads/7014N106_Motor.STEP
python mcmaster_to_usd.py --part 1718K33  --file ~/Downloads/1718K33.step

# 4. Re-run catalog to update USD status
python mcmaster_catalog.py parts.txt --tag my_parts