Kiln

Build and revise 3D assets with your coding agent.

The agent writes JavaScript using Kiln's geometry and material helpers. Kiln runs the program and returns rendered views and structural checks so the agent can review its work. Export the asset as a GLB and keep the source for later changes.

Kiln runs locally. It includes an MCP server, a CLI, a TypeScript library, and skills for authoring, editing, animation review, and scene composition. Your agent supplies the model; Kiln does not require a separate model API key for its tools.

https://github.com/user-attachments/assets/375327bc-58bc-4344-bbb4-985d92c6f63a

Click the gallery banner above or select an asset below to explore in interactive 3D: Typewriter · Solar Sail Courier · Mechanical Peacock · Kestrel Rescue · Anglerfish · Kinetic Wave · Orrery · Orbital Station · Deco Radio · Cathedral · Steam Locomotive · Lighthouse · Alpine Cable Terminal · Research Vessel · Sushi Store · Windmill · Tram · Ribbon Tea Pavilion · Diesel Locomotive · Art Deco Conservatory · Floating Observatory · Deep Sea Station · Unfolding Dragonfly · Vintage Typewriter · Argent Carrier · Noctilus Submarine · Resolute Flagship

Mechanical peacock · Claude Opus 5	Unfolding dragonfly · GPT-6 Astra	Solar sail courier · Gemini 3.8 Flash

Browse the interactive gallery · All examples and model credits

These are saved examples from different authoring runs, not a model ranking. They are historical showcases from earlier Kiln versions, with unvetted modeling issues; they are not golden outputs or reference solutions. Credits, review conditions and build records.

Version 0.8.0 unifies authoring around Discovery and optional requirements, with updated geometry helpers, edit evidence and separate native-agent context. The tagged GitHub archive includes the built runtimes and is installable with npm. An official 0.8.0 package release has not been published. The qualification report records checks and support limits; the progress checkpoint retains the detailed work history.

Install and start an asset workspace

Use Node.js 20.15.0+ on the 20.x line, or 22.2.0 and later, with npm. Bun and a separate model API key are not required for this installation:

mkdir kiln-install
cd kiln-install
npm init -y
npm install "https://github.com/matthew-kissinger/kiln/archive/refs/tags/v0.8.0.tar.gz" --omit=dev --include=optional
npm exec --offline -- kiln-init ../my-assets --harness opencode
cd ../my-assets
# Follow START.md for your harness

The installation stays separate from your asset workspace. Choose claude, codex, opencode, hermes, agy, copilot, or cursor-agent for --harness. The installation guide covers local archive files, existing-workspace upgrades and platform qualification. For a new installation, a maintained Node 22 or 24 LTS release is recommended; Node 20 compatibility accommodates existing distribution-managed installations.

Run from a checkout

For engine development, install Bun 1.4.2, then:

git clone --filter=blob:none https://github.com/matthew-kissinger/kiln
cd kiln
bun install --frozen-lockfile
bun run kiln render examples/crate.kiln.js --out crate.glb --views sheet.png

--filter=blob:none checks out the current tree in full and leaves historical file contents on the server, fetching them only if you ask for an old revision. A plain git clone also works and gives you the whole history up front.

This writes a GLB and a six-view image of an existing program. It makes no model call. Rendering uses the CPU unless a compatible local GPU service is available. Use --render cpu to select the CPU explicitly. Sheets sit on a neutral grey; add --backdrop dark or --backdrop light when an asset's silhouette merges with it; kiln save takes the same flag for the preview it stores.

For anchored CLI edits, import source with kiln source asset.kiln.js, then run kiln edit RETURNED_REF --edits edits.json. The file contains an array of { "oldString": "exact existing text", "newString": "replacement text" } objects. The command returns a new immutable reference and diff without executing source; render that new reference to inspect the result. kiln edit --help describes batch limits and replaceAll.

Using assets in Blender or Unity? Read the handoff guide for direct GLB import, materials, backfaces, named pivots and animation checks. The established exporter remains the default. An experimental community exporter is available for explicit comparison when you need its additional feature preservation; the guide includes activation, rollback and known limitations. Both converters are included in this installation.

History was rewritten on 2026-09-10 to drop 288 MB of gallery renders and launch video that no tool reads, taking a clone from 440 MB to 60 MB, or 49 MB with --filter=blob:none; measured 2026-09-12. Every commit survived and the tree is unchanged apart from those files, but every commit hash changed, so a clone made before that date cannot fast-forward.

Re-cloning is simplest. Before converting an old clone, back up uncommitted work and local branches: the commands below reset the checkout and prune recovery history. Move the tag as well as the branch:

git fetch --tags --force origin
git reset --hard origin/main
git reflog expire --expire=now --all
git gc --prune=now

--force is the load-bearing flag. oss-2026-09-05 was rewritten too, and git will not move a tag that already exists without it: plain git fetch --tags, and even --prune-tags, both report would clobber existing tag and leave the old one in place, holding every removed file reachable. Omit it and .git stays at 228 MB where a fresh clone is 26 MB; run it and the same clone packs to 23 MB.

The gallery images are served from assets.kilnstudio.tools; the 83 poster receipts that attest their bytes stayed in examples/renders/.

Connect your agent

The agent reading guide links to setup, tool schemas and the source revision workflow in plain text.

The installation commands above create a separate asset workspace, register MCP and copy the Kiln skills. Follow its START.md to launch your harness. Setup writes project-local configuration and leaves your global settings unchanged.

If you are developing Kiln from a source checkout, create that workspace with:

bun run build:runtime
node scripts/create-workspace.mjs ../my-assets --harness opencode
cd ../my-assets
# Follow START.md for your harness

Choose claude, codex, opencode, hermes, agy, copilot, or cursor-agent for --harness, then open that harness in the new directory using its generated START.md instructions and accept its project and MCP trust prompts. Sign in to your harness first. The compiled MCP server and CLI accept Node.js 20.15.0+ on the 20.x line, or 22.2.0 and later. Bun is for building and testing the engine; installed commands do not require it. The optional native S