Kiln

Spawn an object into existence.

Kiln is how AI agents make real things, safely. Describe what you want to exist, and your agent designs it, checks it will print, and prints it on your own 3D printer, or has it printed and shipped to you. Every version is kept, Git-style, so you can try the risky idea and keep the one that worked.

The open-source MCP server for 3D printing.

Kiln lets AI agents (ChatGPT, Claude Desktop, Claude Code, Claude Duet, Codex, Cursor, Gemini, Grok, Hermes Agent, OpenClaw, or any custom MCP client) drive real 3D printers end to end — Bambu Lab, Creality, Prusa, Elegoo, Voron, Sovol, AnkerMake, Artillery, FlashForge, QIDI, RatRig, and SparkX. It is compatible with OctoPrint, Moonraker/Klipper, PrusaLink, and Direct USB.

In a single conversation, an agent can design a part, slice it, queue it on the right printer, monitor the camera, recover from failures, and ship the result. You approve every print, or let one printer run on its own for as long as you choose.

Reading this as an AI agent? kiln3d.com/agents is written for you rather than for the person running you: install, MCP config, the design-to-print loop, and exactly what Kiln will refuse to do and why.

pip install kiln3d

"a coaster with a photo of my dog Ash" — start to finish, from one sentence.

Watch the demo →

Version control for 3D printing. Branch a design to try the risky idea, compare any two versions with the numbers, merge the one that printed, and undo anything. See how it works →

Kiln's built in the open. If it made your printing more fun, or just saved you a headache, a ⭐ on the repo helps the next maker find it.

Quick Start

Using Claude Desktop? Install Kiln in one click. Download kiln.mcpb and double-click it — Claude Desktop installs Kiln and wires it in (just Claude Desktop: steps 1 and 2 below are how Codex and every other AI app connect), so those steps aren't yours. Two things still are: OpenSCAD, and Kiln's terms — the command shows them and asks you to type your acceptance, which is why it's yours and not your AI's: uvx --from kiln3d kiln accept-terms. The bundle and that command both run on uv — free, with a one-line install for each platform at that link. If Claude Desktop says the server failed to start, that's uv missing: install it and restart. Updates arrive with the extension, not via kiln self-update.

Using ChatGPT, Claude, Claude Duet, Gemini, Grok, Cursor or Hermes Agent? Nothing to install. Add Kiln inside the app by its address, https://api.kiln3d.com/mcp, and sign in (Claude Duet uses the one you add in Claude; Hermes Agent takes one terminal command, on its page): it designs the part, checks it will print, and shows it in 3D, right in the chat where the app can show it. Each app's page says exactly what was seen there: ChatGPT, Claude, Claude Duet, Codex, Cursor, Gemini, Grok, Hermes Agent. To run your own printer, do the three steps below on the computer next to it.

Using OpenClaw? Tell it to install Kiln from ClawHub and it sets Kiln up on the computer it runs on: see how.

Everyone else — three steps. Then ask your AI to make something.

1. Install

pip install kiln3d

2. Connect your AI — Kiln sets itself up inside Claude Desktop, Claude Code, and Codex:

kiln signin        # create your free account

kiln install-mcp # connects Kiln to your AI apps

Restart your AI app and it can run your printer. (Claude Code and Codex can even run this whole setup for you — the one-prompt version lives at kiln3d.com/install.) Using a different MCP client? kiln install-mcp --print prints the config — or paste it yourself:

Manual MCP config (any client, no sign-in needed)

{

"mcpServers": { "kiln": { "command": "python3", "args": ["-m", "kiln", "serve"] } } }

No install needed? Swap the command for a zero-install runner — "command": "uvx", "args": ["kiln3d", "serve"] (Python), or "command": "npx", "args": ["kiln3d"] (Node). Same server, nothing to pip install.

Drop this into Claude Desktop, Claude Code, Codex, Cursor, or any MCP-capable agent. Runs on the free tier until you sign in.

3. Ask — paste a sentence like this into your agent. Kiln does the rest:

Make me a coaster with my dog's photo on it

That's the whole happy path. Your AI does the designing, slicing, and printing — you never touch a CLI. OS-specific walkthrough (Windows, WSL 2, Linux) at [kiln3d.com/install](https://kiln3d.com/install?utm_source=github&utm_medium=readme).

[!TIP]

kiln doctor checks your whole setup and tells you exactly what to fix. kiln self-update upgrades in place when a new release lands.

Prefer to drive it yourself? (CLI tour)

# Discover printers on your network (mDNS + HTTP probe)

kiln discover

Add your printer, saying which printer it is (see "Supported Printers")

kiln auth --name my-printer --host http://octopi.local --type octoprint --api-key YOUR_KEY --printer-model "Ender 3"

Other types:

kiln auth --name prusa --host http://192.168.1.100 --type prusalink --api-key YOUR_KEY --printer-model MK4

kiln auth --name klipper --host http://192.168.1.100:7125 --type moonraker --printer-model "Voron 2.4"

kiln auth --name bambu --host 192.168.1.100 --type bambu --access-code LAN_CODE --serial SERIAL --printer-model P1S

A printer Kiln doesn't list yet: add who makes it, e.g. --printer-make Anycubic --printer-model "Kobra X"

kiln status # Printer state + job progress kiln upload model.gcode # Upload a file kiln print model.gcode # Start printing kiln slice model.stl --print-after # Slice an STL and print in one step kiln print *.gcode --queue # Batch print kiln wait # Monitor a running print kiln snapshot --output photo.jpg # Webcam snapshot kiln history --status completed # Print history kiln park --plan # Describe the safe park, send nothing; then --step 1, 2, 3 kiln home --plan # Same for the Home button; --plate-clear where Z homes onto the plate kiln filament wipe --plan # Same for the wipe-pad pass; --plate-clear where its plan presses the plate

Every command supports --json for agent consumption

kiln status --json

Global option: --printer targets a specific printer per command. The full command reference is in Project Docs.

Connect a specific agent (Claude Code, Claude Desktop, env vars)

Claude Code — install the plugin (one-time: install uv first if you don't have it — it's free and takes one line):

claude plugin marketplace add codeofaxel/Kiln

claude plugin install kiln@kiln

Or wire it by hand — add to .claude/settings.json (project) or ~/.claude/settings.json (global):

{

"mcpServers": { "kiln": { "command": "kiln", "args": ["serve"] } } }

Claude Code uses your ~/.kiln/config.yaml for printer credentials (set via kiln setup or kiln auth). No env vars needed if a printer is already configured.

Claude Desktop — add to ~/.config/Claude/claude_desktop_config.json:

{

"mcpServers": { "kiln": { "command": "python3", "args": ["-m", "kiln", "serve"], "env": { "KILN_PRINTER_HOST": "http://192.168.1.100", "KILN_PRINTER_API_KEY": "your_key", "KILN_PRINTER_TYPE": "prusalink" } } } }

Set KILN_PRINTER_TYPE to your backend: octoprint, moonraker, bambu, prusalink, elegoo, duet, or usb — or skip env vars entirely if you've run kiln setup.

Any other LLM (OpenRouter) — Kiln works with any model that supports OpenAI-compatible function calling, not just Claude:

export KILN_OPENROUTER_KEY=sk-or-...

kiln agent --model openai/gpt-4o kiln agent --model meta-llama/llama-3.1-70b-instruct --tier essential

Tool tiers auto-match model capability: essential (15 tools) for smaller models, standard (60 tools) for mid-range, full (135 tools) for stronger models. All 880 tools are available over MCP via kiln serve.

Platform & printer setup notes (Linux/WSL 2, Ethernet-only, Bambu)

Prerequisites by printer type

| **Creality K1/K2/Hi/Ender V4