# PrintPal for Gemini: 3D printing tools in Gemini and the Gemini CLI

> Use PrintPal as a custom app in Gemini, in the Gemini CLI, or in agents built with Google's Agent Development Kit.

Page: https://printpal.io/integrations/gemini
Updated: 2026-10-27

**PrintPal for Gemini** connects Google Gemini to [PrintPal](https://printpal.io/), a 3D printing platform, through a free remote MCP server at `https://printpal.io/mcp`. With it, Gemini can search printable 3D models, run print-cost, filament, layer-height and volumetric-flow calculators, answer troubleshooting questions with citations from PrintPal's wiki, and find Arduino and ESP32 build guides.

It works as a custom app in the Gemini app, as an MCP server in the open-source Gemini CLI, and as an `MCPToolset` in agents built with Google's Agent Development Kit.

## At a glance

- **Works in:** Gemini app (custom apps), Gemini CLI, Google ADK agents
- **Price:** Free. AI 3D generation uses PrintPal credits and is optional.
- **Account needed:** No
- **Server URL:** `https://printpal.io/mcp`
- **Transport:** Streamable HTTP
- **Tools:** 16

## Where to get it

- MCP server URL (works today): https://printpal.io/integrations/gemini#install
- Official MCP Registry: io.printpal/printpal: https://registry.modelcontextprotocol.io/v0/servers?search=io.printpal/printpal

## Features

- **Model search:** Find printable STL, 3MF and OBJ models from the PrintPal community library with author and license.
- **Filament and cost math:** Grams to metres, spool remaining, cost per print and a suggested selling price.
- **Cited fixes:** Warping, stringing, under-extrusion and error codes, answered from the full PrintPal wiki article with a link.
- **Gemini CLI ready:** One `gemini mcp add` command, or a few lines in `settings.json`, and the tools are available in every session.
- **Build your own agent:** Point an ADK `MCPToolset` at the server to give your own Gemini agent 3D printing skills.
- **Design hand-off:** Gemini drafts a CAD brief for PrintPal's AI CAD agent or opens the AI 3D generator with your prompt.

## How to add PrintPal to Gemini

1. In the Gemini app, open **Settings → Connected apps → Custom apps** and choose **Add**.
2. Paste `https://printpal.io/mcp` as the server URL. No authentication is needed.
3. In a chat, mention **@PrintPal** and ask your question.
4. For the Gemini CLI, run the command below instead and restart the CLI.

Custom apps in the Gemini app roll out by plan and region. The Gemini CLI works everywhere.

### Gemini CLI

Adds PrintPal to your Gemini CLI settings.

```bash
gemini mcp add --transport http printpal https://printpal.io/mcp
```

### Gemini CLI settings.json

Or add it by hand to `~/.gemini/settings.json`. Add a `headers` entry with `Authorization: Bearer $PRINTPAL_API_KEY` to enable direct AI generation.

```json
{
  "mcpServers": {
    "printpal": {
      "httpUrl": "https://printpal.io/mcp",
      "timeout": 60000
    }
  }
}
```

### Google Agent Development Kit (Python)

Give your own Gemini agent PrintPal's tools.

```python
from google.adk.tools.mcp_tool.mcp_toolset import MCPToolset
from google.adk.tools.mcp_tool.mcp_session_manager import StreamableHTTPConnectionParams

printpal = MCPToolset(
    connection_params=StreamableHTTPConnectionParams(url="https://printpal.io/mcp")
)
```

## Prompts to try

- @PrintPal find a printable cable organizer for my desk.
- @PrintPal how much filament is left on a spool that weighs 612 g with a 210 g empty spool?
- @PrintPal my ABS print is warping at the corners. What should I change?
- @PrintPal show me a beginner ESP32 build guide with a printed case.
- @PrintPal design a 3D-printable phone stand with a 15° tilt and a slot for a USB-C cable.

## 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 |

## Who it is for

- **Terminal-first makers:** Ask the Gemini CLI for a print cost or a layer height without leaving your shell.
- **Agent builders:** Add 3D printing knowledge to a support bot, a classroom assistant or a print-farm agent.
- **Quick answers on the go:** Check a filament setting or a fix from your phone while you stand at the printer.

## Privacy and data

- 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_source` tag 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.

## FAQ

### Can Gemini help with 3D printing?

Yes. With the PrintPal app connected, Gemini can search printable 3D models, calculate filament usage and print costs, find magic-number layer heights, check volumetric flow, and troubleshoot failed prints with citations from PrintPal's wiki.

### How do I add an MCP server to the Gemini CLI?

Run gemini mcp add --transport http printpal https://printpal.io/mcp, or add an mcpServers entry with "httpUrl": "https://printpal.io/mcp" to ~/.gemini/settings.json, then restart the CLI.

### Does PrintPal work in the Gemini app?

Where your Gemini plan supports custom apps, add https://printpal.io/mcp under Settings, Connected apps, Custom apps, then mention @PrintPal in a chat. No sign-in is required.

### Can I use PrintPal tools in my own Gemini agent?

Yes. In Google's Agent Development Kit, create an MCPToolset with StreamableHTTPConnectionParams(url="https://printpal.io/mcp"). The same tools are also available as REST endpoints described at https://printpal.io/mcp/openapi.json.

### Is it free?

Yes. All tools except direct AI 3D generation are free and anonymous. Generation either returns a prefilled link to printpal.io or, with your PrintPal API key, uses your credits.

### What data does PrintPal receive from Gemini?

Only the tool inputs Gemini sends, like a search phrase or calculator numbers. PrintPal does not see your conversation, collects no personal data and does not use requests for training.

## Related integrations

- [PrintPal for ChatGPT](https://printpal.io/integrations/chatgpt): Search printable models, price prints, fix failed prints and hand off to AI 3D or CAD design, right inside ChatGPT.
- [PrintPal for Claude](https://printpal.io/integrations/claude): A remote MCP connector for Claude.ai, Claude Desktop and Claude Code with models, calculators, a cited wiki and CAD hand-off.
- [PrintPal MCP Server](https://printpal.io/integrations/mcp-server): One free remote MCP endpoint with 16 tools for 3D printing. Works in any client that speaks Streamable HTTP.
- [PrintPal for Cursor](https://printpal.io/integrations/cursor): Download printable models into your repo, write printable OpenSCAD, check meshes and price G-code from the Cursor agent.

## More

- All integrations: https://printpal.io/integrations
- PrintPal for LLMs: https://printpal.io/llms.txt