The PrintPal MCP server: 3D printing tools for any AI agent
One URL gives ChatGPT, Claude, Gemini, Cursor, VS Code and any other MCP client 16 tools for 3D printing. Stateless Streamable HTTP, no OAuth, listed in the official MCP Registry.
- Free
- No OAuth
- Stateless JSON (no SSE)
- Official MCP Registry
- material $0.90 · electricity $0.05
- failure allowance (5%) $0.05
- cost per print $1.00
What is PrintPal MCP Server?
The PrintPal MCP server is a free, public Model Context Protocol server at https://printpal.io/mcp, published by PrintPal as io.printpal/printpal in the official MCP Registry. It gives AI assistants and agents 16 tools for 3D printing: searching a community library of printable models, print-cost and calibration calculators, a vendor-neutral troubleshooting wiki with full-text fetch for citations, Arduino and ESP32 build guides, and hand-offs to PrintPal's AI 3D generator and parametric AI CAD agent.
It speaks stateless Streamable HTTP with plain JSON responses, needs no authentication, and also exposes every tool as a REST endpoint with an OpenAPI 3.1 description. An optional PrintPal API key unlocks credit-metered AI 3D generation.
Updated October 27, 2026 · Made by PrintPal
At a glance
- Endpoint
https://printpal.io/mcp- Transport
- Streamable HTTP, stateless, JSON responses (no SSE)
- Authentication
- None. Optional
Authorization: Bearer <API key>for AI generation. - Tools / prompts / resources
- 16 / 3 / 2
- Registry name
io.printpal/printpal- Server card
- /.well-known/mcp.json
- REST + OpenAPI
POST /mcp/rest/<tool>· /mcp/openapi.json- Price
- Free
What PrintPal MCP Server can do
Works in every MCP client
ChatGPT, Claude, Gemini, Cursor, VS Code with GitHub Copilot, Windsurf and any client that supports remote Streamable HTTP servers.
No auth, no sessions
Stateless JSON-RPC over HTTP with CORS enabled. Nothing to sign in to and nothing to clean up.
Built for citations
search and fetch follow the connector contract, so assistants can read a full wiki article and link to it.
MCP App widget
Model search results come with an HTML widget (ui://widget/printpal-models-v1.html) that renders interactive model cards in hosts that support MCP Apps.
Honest annotations
Every tool declares readOnlyHint, destructiveHint and openWorldHint. Only generate_3d_model has a side effect, and only with your key.
REST and OpenAPI too
Call any tool with a JSON body at /mcp/rest/<tool> from scripts, Zapier or Custom GPT Actions.
How to connect the PrintPal MCP server
- Copy the server URL:
https://printpal.io/mcp. - Add it to your client as a remote (HTTP) MCP server. Pick your client below for the exact command or config.
- Leave authentication off. Add
Authorization: Bearer pp_live_…only if you want AI 3D generation on your own credits. - Ask your assistant a 3D printing question. It will discover the 16 tools automatically.
Clients that only support local stdio servers can bridge with npx -y mcp-remote https://printpal.io/mcp.
Remote MCP, Streamable HTTP.
https://printpal.io/mcp
claude mcp add --transport http printpal https://printpal.io/mcp
gemini mcp add --transport http printpal https://printpal.io/mcp
{
"mcpServers": {
"printpal": { "url": "https://printpal.io/mcp" }
}
}
{
"servers": {
"printpal": { "type": "http", "url": "https://printpal.io/mcp" }
}
}
{
"mcpServers": {
"printpal": { "serverUrl": "https://printpal.io/mcp" }
}
}
Bridges a local stdio client to the remote server. Requires Node.js 18+.
{
"mcpServers": {
"printpal": {
"command": "npx",
"args": ["-y", "mcp-remote", "https://printpal.io/mcp"]
}
}
}
Every tool is also a plain JSON endpoint.
curl -s https://printpal.io/mcp/rest/calculate_print_cost \
-H 'Content-Type: application/json' \
-d '{"print_weight_grams": 45, "print_time_hours": 3.5}'
Prompts to try in MCP Server
The 16 PrintPal tools
Every AI assistant integration exposes the same tools from the PrintPal MCP server. Fifteen are read-only; only generate_3d_model can spend credits, and only when you add your own API key.
| Tool | What it does | API key? |
|---|---|---|
search_3d_models | Find printable STL, 3MF and OBJ models in the PrintPal community library, with thumbnail, author, license and stats. | No |
get_3d_model | Details, files, license and the download link for one model. | No |
calculate_print_cost | Material, electricity, machine wear, labor and failure allowance, plus a suggested selling price. | No |
calculate_filament_usage | Filament grams to metres to cost, and how much is left on a spool. | No |
calculate_layer_heights | Z-axis "magic number" layer heights for your printer's leadscrew and stepper. | No |
calculate_volumetric_flow | Check a print speed and layer height against your hotend's volumetric flow limit. | No |
search_learning_resources | Search the vendor-neutral 3D printing wiki, OpenSCAD and AI CAD docs, video tutorials and Academy courses. | No |
search_build_guides | Find Arduino / ESP32 + 3D-printed project guides by idea, difficulty, time and cost. | No |
get_build_guide | Bill of materials, downloadable files and every step of one build guide. | No |
design_parametric_cad | Turn a part description into a precise CAD brief and a link that opens PrintPal's AI CAD agent prefilled. | No |
generate_3d_model | AI text-to-3D and image-to-3D. Without a key it returns a prefilled link to printpal.io; with your API key it starts the generation on your credits. | Optional |
check_3d_generation | Poll a generation started with your key and get the download link. | Yes |
find_3d_printing_tool | Recommend the right free PrintPal browser tool or calculator for a task. | No |
get_pricing_and_plans | What is free, how credits work and which plan fits. | No |
search | Search everything on PrintPal at once: models, tools, wiki, docs, videos, guides and courses. | No |
fetch | Read any search result in full (for example a wiki article) so the assistant can quote and cite it. | No |
Built-in prompts
Clients that support MCP prompts (Claude, Cursor and others) list these as one-click starting points.
| Prompt | Arguments | What it does |
|---|---|---|
troubleshoot_print | problem, printer, material | Diagnoses a failed print and cites the PrintPal wiki articles it used. |
design_a_part | what, dimensions | Checks the library for an existing model, otherwise drafts a CAD brief and opens the AI CAD agent. |
plan_a_build | idea, skill_level | Finds a matching build guide with its bill of materials and steps. |
Endpoints
Everything the server exposes over HTTP.
| Path | Purpose |
|---|---|
POST /mcp | JSON-RPC over Streamable HTTP (stateless). Batches supported. |
GET /.well-known/mcp.json | Server card: transport, auth, tools and links, for crawlers and registries. |
GET /mcp/openapi.json | OpenAPI 3.1 description of the REST shim, for Custom GPT Actions and HTTP agents. |
POST /mcp/rest/<tool> | Call one tool with a JSON body and get its structured result. |
GET /mcp/health | Liveness, tool count and supported protocol versions. |
GET /llms.txt | Markdown overview of PrintPal for LLMs, also exposed as the printpal://llms.txt resource. |
Who uses PrintPal MCP Server
Agent builders
Add 3D printing knowledge to a support bot, a print-farm assistant or a classroom tutor.
IDE assistants
Let Copilot, Cursor or Windsurf look up models, docs and print costs while you build hardware projects.
Automations
Call the REST shim from Zapier, n8n or a cron job to price prints or search the library.
Researchers and evals
A stable, public, read-only MCP server is a handy fixture for testing MCP clients.
Privacy and how it works
What PrintPal MCP Server sends, stores and never touches.
- No account, sign-in or OAuth. The server is public and stateless, so nothing is stored between calls.
- PrintPal only sees the tool inputs the assistant sends (search text, calculator numbers, a model id). It does not see your conversation.
- No personal data is collected and nothing is used for AI training.
- Links back to printpal.io carry a
utm_sourcetag so we can see which assistant sent the visit; no identifier is attached. - Your optional API key is only sent to printpal.io and only unlocks credit-based AI generation.
Frequently asked questions about PrintPal MCP Server
What is the PrintPal MCP server?
It is a free, public Model Context Protocol server at https://printpal.io/mcp that gives AI assistants 16 tools for 3D printing: model search, print-cost and calibration calculators, a cited troubleshooting wiki, Arduino and ESP32 build guides, and hand-offs to PrintPal's AI 3D generator and AI CAD agent. It is listed in the official MCP Registry as io.printpal/printpal.
Does the PrintPal MCP server need authentication?
No. Every tool works anonymously. An optional Authorization: Bearer header with a PrintPal API key unlocks direct AI 3D generation and generation status checks, billed to your PrintPal credits.
Which MCP clients does it work with?
Any client that supports remote Streamable HTTP servers, including ChatGPT, Claude.ai, Claude Desktop, Claude Code, Gemini CLI, Cursor, VS Code with GitHub Copilot and Windsurf. Clients limited to stdio can use npx mcp-remote https://printpal.io/mcp.
Does it use SSE?
No. The server is stateless Streamable HTTP and always answers with plain JSON. GET /mcp returns 405 because it does not open a server-to-client stream, which the specification allows.
Can I call the tools without an MCP client?
Yes. Each tool is available at POST https://printpal.io/mcp/rest/<tool> with a JSON body, and https://printpal.io/mcp/openapi.json describes them in OpenAPI 3.1 for Custom GPT Actions and other HTTP callers.
Is the PrintPal MCP server free?
Yes. Only direct AI 3D generation costs PrintPal credits, and only when you send your own API key. Without a key, generate_3d_model returns a prefilled link to printpal.io instead.
Does it store my data?
No. The server is stateless and keeps no session. It only receives the tool arguments your client sends, collects no personal data and does not use requests for training.
Get PrintPal MCP Server
One free remote MCP endpoint with 16 tools for 3D printing. Works in any client that speaks Streamable HTTP. Free to install. See all integrations.