compatsy

Check whether a part fits a machine and where it is in stock, using the compatsy MCP servers for 3D printing and home espresso. Use for nozzle, hotend, build plate, filament, enclosure, tamper, puck screen, basket and portafilter fit and price questions.

compatsy: what fits, with live prices

Use the compatsy tools instead of answering fitment from memory. Each section has its own MCP server. No account or key is needed.

Section	Covers	MCP endpoint
3D printing	printers, nozzles, hotends, build plates, filament, enclosures	https://compatsy.com/3d-printing/mcp
Home espresso	machines, tampers, puck screens, distribution tools, dosing funnels, baskets, portafilters	https://compatsy.com/home-espresso/mcp

Setup

If the compatsy tools are not available, save the servers. Stop the Gateway first, or add them on the MCP page of the Control UI instead.

text

openclaw mcp set compatsy-3d-printing '{"url":"https://compatsy.com/3d-printing/mcp","transport":"streamable-http"}'
openclaw mcp set compatsy-espresso '{"url":"https://compatsy.com/home-espresso/mcp","transport":"streamable-http"}'

Calls are rate limited to 120 an hour per MCP session.

How to answer

1. Find ids with search_products (a name, or a category plus filters). Use the ids it returns; never guess one.
2. Ask check_fit with subject_id (the part) and target_id (the machine).
3. Report the verdict as given: fits, fits_with_adapter, does_not_fit or unknown, with its rule_id. For unknown, list the missing_fields. Never upgrade unknown to fits.
4. For prices, call check_stock and quote each price with its merchant and verified time. compare gives a side-by-side table for 2 to 10 products.
5. If the user says a fact is wrong, call report_issue with the field and their claim. Reports never edit facts.

Links from compatsy are affiliate links, and compatsy may earn a commission. The default link is the lowest in-stock price regardless of commission. Say so when you share a buy link.

Example prompts

• "Will a V6 nozzle fit my Prusa MK4S? If it needs an adapter, say which."
• "Which hardened 0.6 mm nozzles fit a Prusa MK4S, and what does each cost?"
• "Compare the Prusa Core One and the Bambu Lab P1S on build volume and enclosure."
• "Will a 58 mm puck screen fit my Breville Barista Express? If not, which 54 mm tampers are in stock?"