Construct

https://github.com/user-attachments/assets/8c39a196-9910-46a0-9746-4f15965adf15

_{Construct in Hermes Agent, in 90 seconds. It works the same way in Claude Code, any MCP client, any OpenAI-compatible endpoint, or the Claude and ChatGPT apps.}

Construct is a tool for AI agents. It turns everything that can be found out about a thing into one exact, checked description of it: its named parts at their real sizes, how they fit together, open and move, and how each one is known, measured or guessed. An agent does the research and writes the description. Construct checks it and builds from it, and the same description always gives the same result. Put constructs together and they make a world: a room, a street, a whole game level. Inside a world every construct is still whole, with its own parts, sources and joints, so you can move, reuse or open any of it.

Describe a thing, or show a place. Get a hologram, a 3D model, a print, a kit, or a whole world. Ask any AI agent in plain words and it builds an animated model in lines of light, in the Measured Light style. The result is a single web page you can open anywhere, and it is honest about what is known. The same construct can also become a 3D model with named parts and working joints, a print, a model kit, a CAD file or a film, or one piece of a world made with others.

A world can be asked for in plain words, put together from constructs you already have, or made from a single picture. Given one picture of a place, it builds the place zero-shot. Stortorget, Stockholm's old square, was made from a single photograph and stands almost exactly as the photograph shows it. Rain Harbour is a game level made from one concept picture, ready to open in Godot, Unity or Unreal. And a world comes apart again, construct by construct: rearrange it by hand in Hermes, or take any one construct out to open, export or reuse on its own.

_{Constructs (top): the Sainte-Chapelle and the Toyota Land Cruiser FJ62 by Claude Opus 5.5, KESTREL, an invented ice tug, by GPT-6.1 Sol, each in masterpiece mode. Worlds (below): Rain Harbour, a game level, and Stortorget at Christmas, each made by GPT-6.1 Sol from one picture; the shed and the things around it, made of constructs from the gallery. Open the gallery to orbit them, replay the assembly and read the labels; how KESTREL was made, how Stortorget was made.}

• Construct for Hermes. A native Hermes plugin. Ask for a thing in plain words and the construct appears live in the chat, with its 3D model, kit and NetLogo runs beside it. You can also place your constructs together into worlds. hermes plugins install rtmandreyev/construct#hermes/construct (what it does, Villa Savoye in Hermes, step by step, worlds, step by step).
• Every piece stays separate. In a world made from one picture you can still handle each construct on its own: move a car, turn a tower, swap the signs, open a door on its hinge, export it to Blender or Godot, or reuse a building in another level (Rain Harbour, before and after).
• Any agent, any model. Claude Code, Hermes, any MCP client or any OpenAI-compatible endpoint, or by hand.
• Honest about what is known. Every part says how it is known, for its size and its shape separately, and every guess is shown in a shade of how firmly it is held. What each mark means.
• One house style. Models never choose the colours, so every construct looks like it belongs with the rest.
• It repairs itself. Every problem comes back with where it is and how to fix it.
• Nothing to install. It needs only Python's standard library and a browser. There are no API keys and no network service inside Construct.

Find your path

You…	Construct gives you	Start here
Everyday
want a model of anything you can describe	A thing you describe, as a construct you can turn, replay and share	Make a construct
want a digital copy of something you own	Your chair, guitar, camera or heirloom in 3D from your photos and whatever its maker publishes, showing what was measured and what was guessed	Copy your thing
are planning a change to your home or garden	Your shed, room or garden as a model to try the change on first: a deck, shelves, an extension, a new layout. A planning model, not a survey	Try it on a copy
want to customise or restore a vehicle	Your car, bike or scooter from its published sizes and your photos, your parts told apart from the factory's: try wheels or a new colour, plan a restoration, make a model of it	Your vehicle
need a part that is missing or broken	A knob, bracket or cover drawn to the thing it fits, as a print or a CAD file someone can make	Make the part
want a place from a photo: a square, a street, a building, your neighbourhood	One photograph is enough to start (Stortorget, from one); more pictures make it closer, up to a digital twin, house by house, each part saying how it is known	Stortorget, start to finish
want your things together in one place	Your house with your furniture, your car and scooter under it, a ship over the roof: whole constructs placed at real size, arranged by asking or by hand	Worlds, step by step
want a model kit of your own thing	Your scooter, house or guitar as a kit to print, glue and paint, with a booklet (one to open)	A kit of your own
want to show someone what you mean	A model a builder, a fabricator or a friend can turn and measure, and a file for their own tools	Show what you mean
Professionals and creators
are a maker with a printer or CAD	A construct as one checked print at your printer's largest size (Tompion's clock: 21 cm on a desktop printer, 10½ hours in PrusaSlicer), a model kit with plates, a booklet and its steps in 3D (five to open), and true CAD shapes in FreeCAD and STEP	Print, kit, CAD
create new ships, creatures or places for a game, film or story	New things designed from real ones: a construct, a 3D model with working parts, a film (see KESTREL, an invented ice tug)	New things from real ones
have software or a documented system you wish were a physical product	Its documented functions mapped to controls, displays and the parts inside, what the documents fix kept apart from what is designed (one worked example: a software synthesizer as a 61-key instrument)	Documentation → product
are a game developer	Props in named parts at their real size, with doors and lids on working hinges in Godot, FBX for Unity and Unreal; models of what your game needs instead of stock ones; a whole level from one concept picture (Rain Harbour: 21 constructs placed 50 times, a hero car, one command to a Godot map)	Into a game engine
are a 3D artist	A construct or a whole world in Blender with its build, joints, metal and finish on sliders, painted from a small material map (the Villa Savoye, 396 parts, and the Villa lived in, a world of 13, rendered in Cycles); OBJ in quads to model over; FBX and USD	Into Blender
work in film and motion	A construct that assembles across your track, pausing, surging and flaring with the music, shimmering with a vocal stem (three films); keyed reveals in Blender; a world's named views as shots	Film mode
are an educator or researcher	An agent-based model's run drawn as a construct, compared, printed, filmed	Models come alive
work in a museum or archive	Reconstructions where every part says how it is known (measured, traced, seen in a photo, designed), sources cited and the critic's verdict kept: Tompion's clock from the Royal Collection's record, Stortorget house by house	Honest reconstructions
are a developer	A scene contract that is data, a check that returns each problem with its path and a fix, the same scene always built the same; a command line, an MCP server, skills, and a Hermes plugin with thirteen tools (construct_world, construct_export…)	Build on it

New in 1.3

Every change with pictures and the commands to try it: What's new in 1.3, a walkthrough.

• Worlds. Whole constructs placed together in one scene, each keeping its own parts. Put your chair, clock and synthesizer in your house, your cars under it and a ship over the roof, or build a street, a market square or a game level. The world's audit says what overlaps, what runs into the house it stands in, and what stands where a door opens. Six worlds ship to start from. Worlds, step by step · the format
• A world from a picture, in masterpiece mode. Attach a photo or a concept picture. Hermes plans the pieces, builds each new construct in its own masterpiece rounds with a fresh critic and places them at real size. Then it runs the world itself through rounds against the picture. Two worlds were made this way, each from one picture: Rain Harbour, a game level, and Stortorget, Stockholm's old square at Christmas.
• Arranged by hand in Hermes. Use Arrange on a world's card to drag a construct onto any floor, table or roof, turn it or lift it, add one from the library, and save, all without calling a model. There is a Worlds tab, with groups of your own and previews. The plugin ships 24 constructs (16 in 1.2.1) and all six worlds, the two from pictures with their artwork. A level made from one prompt can be remade by hand: Rain Harbour, before and after.
• More ways out. FBX, USD and USDZ (through Blender); a Godot game map, where everything that stays put is one static body and every hinged or sliding part moves on its own joint; and the Blender add-on imports a world. Every construct now finishes with its own material map, which every export uses by default, and its artwork (signs, labels, screens) exports as textures in glTF and OBJ.
• Sturdier masterpiece rounds, from two long runs: ties recorded, artwork kept in checkpoints, references carried from round to round, more time on request (rounds extend), colour judged in the solid view.

New in 1.2

Every change with pictures and the commands to try it: What's new in 1.2, a walkthrough.

• Construct for Hermes. A native Hermes plugin: ask for a thing in plain words, and the construct appears live in the chat; the 3D model turns in it, a kit steps through in 3D, exports are read back and summarised, long work runs in the background. hermes plugins install rtmandreyev/construct#hermes/construct (what it does). Tested on Villa Savoye, from the request to a printable kit: step by step →
• New things from real ones. KESTREL, an invented 120 m ice tug, from its brief to its joints in Godot: the studies it reasoned from, thirteen masterpiece rounds, then a more detailed version that kept all 256 parts and added 242. Both in the gallery, Apache-2.0, with every brief.
• Documentation → product. A software synthesizer's 354-page manual made into a 61-key instrument concept in one 64-minute session, with the prompt and the documents it wrote, and plainly what it showed and what it did not. The walkthrough →
• Designed to a requirement. A designed part names the requirement it realises (what you asked for, or what a document says it does) and stays honestly designed; a new design is captioned ORIGINAL DESIGN.
• Checked harder. A part that would tip over (tips), a pillar through a window (crosses-glass), a solid left open (open), a number in the text that no longer matches its fact (stale-number), and pokes confirmed four times finer.
• A critic that stands apart. Sealed critic packets with only the renders, the references and your request; a blind verdict cannot be rewritten.
• Cleaner 3D, bigger constructs. Solids wound outward, so Blender's normals and booleans agree; up to 1,024 parts and 48,000 lines; glued joints inside joints for Godot; kit boards that lie flat.

New in 1.1

Every feature with pictures and the commands to try it: What's new in 1.1, a walkthrough. And one construct taken through all of it, step by step: A longcase clock, end to end.

• Your own formats. Adapters: what a construct holds, where to read it and the rules that keep an adapter honest, with a template that writes a parts sheet and an STL per part. Write your own →
• Honest in finer shades. A part's size and its shape known apart, every guess in a shade of how firmly it is held. Press P.
• See it as a solid. Press S in any construct; check --fit names what pokes through or floats.
• Contact you can trust. check follows support through the solids, not their boxes: a part that only seems to rest on another, or hangs on a wire-thin strut, is named with the gap and the part to rest it on. Found from a desk fan two models built; it closed three gaps in the gallery.
• Cleaner 3D. Smoother solids, OBJ that subdivides cleanly, triangle quality reports, for Blender and any 3D program.
• Ready for game engines. Glued pieces with working hinges for Godot, pieces that break apart and settle, colliders, seeded variants.
• CAD. True CAD shapes in FreeCAD, with their joints, and STEP for any CAD program.
• Prints. One checked print at the largest size your printer takes, voxel or exact, with engraved line art.
• Model kits. A construct as a kit to print, glue and paint: numbered plates, a booklet drawn as a kit sheet, the same steps in 3D, every piece printable on its own. A first version, not yet built by a person.
• Models come alive. A NetLogo extension: one command in NetLogo turns a run into a construct, with a replay bar, a legend and a How to read it panel, in views chosen for the data. Runs side by side for a lesson, a printable worksheet, CSV and Cite this run; a run as a film or a 3D model in Blender, or as plates you can stack. 388 of the Models Library's 445 models record with no edits.

Examples

Worlds. Rain Harbour and Stortorget were each made in Hermes from one picture and one request, zero-shot. Rain Harbour is a game level from a concept picture: 21 constructs placed 50 times, every sign in real English and Chinese, and a drivable hero car. Stortorget comes from one photograph of Stockholm's old square: eight real houses researched one by one, one market stall placed 41 times, and the tree, all standing almost exactly as the photograph shows them. The Villa Savoye, lived in, is made of your own constructs: the house with its furniture, a Braun, a Revox, a Leica, SERUM, an FJ62 and a DB5 under the pilotis, and KESTREL far off over the roof. Worlds, step by step →

_{Left, the one photograph Stortorget was asked from (Ximonic, CC BY-SA 4.0); right, the world made from it, rendered from the same place.}

_{Every world as it ships, imported into Blender with Construct's add-on, each construct finished with its own material map.}

Provenance and solids. On the left, the Duomo di Milano in provenance shades (P): verified sizes in cyan, traced shapes in blue, and every guess a deeper amber the more firmly it is held. On the right, the same Duomo as a solid (S), the way a modelling program shows it. Museums and archives →

Film mode. A construct assembling across a piece of music. Film and motion →

Game engines and Blender. The FJ62 in Godot, knocked apart into its pieces, and the same car going from light to a finished model. Game developers → · 3D artists →

Prints and CAD. An exact print of the FJ62 beside its voxel print; the Yamaha CFX and the Leica M3 in FreeCAD. Makers →

Model kits. Four constructs as kits to print, glue and paint: the Yamaha CFX piano (1:12, 54 pieces), Tompion's year-going clock (1:12, 34 pieces), the VW T1 Samba (1:16, 98 pieces) and an owner's Vespa GS 150 (1:12, 28 pieces), each with its steps in 3D and a booklet to print. Open them in your browser, or download their plates: the kits in the gallery. Makers →

NetLogo runs. A simulation's whole run as a construct, time as its height. Educators and researchers →

Beyond objects. The same visual language works for ideas and data. Here a classic NetLogo agent-based model, Uri Wilensky's Simple Viral Marketing, was rebuilt to run live in the browser and drawn as a construct: five hundred people, one product, word of mouth and a little advertising. The floor is the social network, and each person rises to the moment they adopted, so you can watch an idea spread and see who it reaches last, and why.

_{Open the live model to build new networks, run them tick by tick and compare a hundred runs with NetLogo's own. The model is © 2012 Uri Wilensky; this example is under CC BY-NC-SA 3.0 (see License).}

How it works

A scene is data, never code: the agent says what the thing is, and Construct decides how it looks. That split is what keeps every construct honest and in one style. In masterpiece mode the review becomes a loop, judged by a critic that never saw the authoring.

flowchart LR
    A["you ask"] --> S["the agent writes<br/>a scene"]
    S --> C["Construct<br/>checks it"]
    C -- "problems, with fixes" --> S
    C --> B["Construct builds<br/>construct.html"]
    B --> R["the agent reviews<br/>its pictures"]
    R -- "masterpiece: another round" --> K["the critic compares<br/>with the best so far"]
    K -- "better: keep it" --> S
    K -- "not better: keep the best" --> S
    R --> D["you get the best version"]

• You can see how each part is known. Press P in any construct and every part is coloured by whether it is verified, supplied by you, inferred or decorative. Press S to see it as a solid, the way a modelling program or a print shows it.
• The check runs to zero. Floating parts, claims without evidence and details too fine to see are reported, with fixes, before anything is built.
• The critic is independent. It is a fresh model that compares each new version with the best so far without knowing which is which. Only a better version is kept.
• Masterpiece stops when it stops improving: after two rounds without a better version, after 12 rounds, or after two hours. In the author's own blind comparisons, on two subjects, there was no visible improvement after about round 12, so more rounds mostly cost time.

_{The critic at work: the Sainte-Chapelle at rounds 1, 8 and 15 of a run by Claude Opus 5.5, made before masterpiece had its 12-round cap. The flèche gains its tiers, and the window tracery, buttresses and pinnacles fill in.}

The whole process, with a construct improving round by round, is in How a construct is made. What you see in a construct, and why models never choose its colours, is in The Measured Light style.

Install

Construct runs from a copy of this repository. There is nothing to install system-wide. Clone it and build the skills for your agent:

git clone https://github.com/rtmandreyev/construct.git
cd construct
python3 construct_hologram/package.py --out dist    # builds the Claude Code and Hermes skills

Then add the skill to your agent, or use Construct directly:

Host	How to add it
Claude Code	claude --plugin-dir dist/claude-code/construct for one session, or copy dist/claude-code/construct/skills/construct into .claude/skills/
Hermes, the plugin	hermes plugins install rtmandreyev/construct#hermes/construct: thirteen tools, the construct live in the chat, worlds, 3D models, kits and NetLogo runs in Hermes Desktop (Construct for Hermes)
Hermes, the skill alone	hermes skills install rtmandreyev/construct/skills/construct, or copy dist/hermes/construct into ~/.hermes/skills/
Any MCP client	Add {"mcpServers": {"construct": {"command": "python3", "args": ["/path/to/construct/construct_hologram/server.py"]}}}
Claude Desktop, the MCP server	Open the .mcpb file from the latest release: Claude Desktop installs it with a double-click (Python 3.10 or newer)
Any OpenAI-compatible model	python3 construct_hologram/cli.py author "..." --base-url ... --model ... --key-env ... --out scene.json
By hand	The command line below; no model needed
Blender	python3 scripts/build_blender_extension.py, then Edit → Preferences → Get Extensions → Install from Disk with the zip in dist/

Quick start

In the Claude or ChatGPT app, no terminal. Download Construct, give the app its folder and your photos, and ask. The Claude app's Cowork and the ChatGPT app's Codex both read the skill and build the construct for you. Construct in the Claude or ChatGPT app →

In your agent, just ask in plain words: "a masterpiece of the Sydney Opera House", or "a masterpiece construct of my guitar from these photos". The agent does the rest and tells you what it is doing. The constructs at the top of this page were all made in masterpiece mode, rounds judged by a second, independent model: ask for it for anything you care about.

To try Construct without a model, fill in a ready-made template by hand:

C=construct_hologram/cli.py
python3 $C params book --variant paperback --output book.json   # fill in the facts you know
python3 $C check book.json             # audit: PASS, or paths and fix hints
python3 $C build book.json --out out   # out/construct.html: open it in any browser
python3 $C review book.json --out out  # out/review/*.png: stills to judge it by

Once a construct is open, drag to orbit and scroll to zoom. R replays the assembly, L shows the labels, T hides the text on its surfaces, P shows how each part is known, S shows it as a solid, and 1–6 move between views.

Modes

A mode sets how much effort goes into a construct. Say one in your request, or say nothing and the skill picks one and tells you why before it starts.

Mode	What it does	When it stops	Rough cost	Use it for
fast	One pass with self-review	About 10 minutes (30 for a richer subject)	Cents with DeepSeek V4.1 Flash	Generic subjects, simple objects, quick requests
masterpiece	Rounds judged by an independent critic, each version compared with the best so far	Two rounds without a win, 12 rounds, or 2 hours of active work	Up to 2 hours of frontier-model tokens	A named car, landmark or building whose likeness matters
timeboxed	Masterpiece in 2 hours in all: the critic's time counts too	Two rounds without a win, 12 rounds, or 2 hours in all	Up to 2 hours, fewer rounds when the critic is slow	When you want masterpiece done within two hours
unbounded	The same rounds, with no cap and no time limit	Only after two rounds without a win	Many rounds and hours, a high token cost	Only when you ask for it by name

Masterpiece's two hours count only the agent's own work. The critic's turns come on top, so a run with a slow critic can take three hours or more. timeboxed stops at two hours in all. The skill never picks timeboxed or unbounded on its own, because the critic finds an improvement almost every round, so a run can go on for hours. Every round is reported, so you can stop it whenever you like.

Models

Any capable model can make a construct, but some subjects need a stronger one. From the evaluation runs:

• Named subjects in masterpiece mode (a car model, a landmark): a Sol or Opus class model (tested: GPT-6.1 Sol, Claude Opus 5.5). A smaller model given such a subject says so and recommends them.
• Simpler objects in fast mode: DeepSeek V4.1 Flash does as well as those on objects such as a tape deck, a watch or a camera (a toy xylophone with its own finish map: about nine minutes).
• Worlds: placing and arranging works with any of the models above. A world from a picture in masterpiece mode is long work for a strong model: Rain Harbour and Stortorget were each about a day of GPT-6.1 Sol, every construct built by its own subagent. Say "fast" for one pass each. Worlds were also tested in Hermes Desktop with DeepSeek V4 Pro.
• Small models (tested: MiniMax M3.1 Flash, Thinking Machines Inkling, NVIDIA Nemotron 3.5 Super VL) are not recommended: in about half of their runs they did not save a scene, and they made scale errors.

Requirements

Construct is deliberately small. You need:

• Python 3.10 or newer. Nothing else to install: no packages, no virtual environment.
• For review stills, a Chromium-family browser you already have (Chrome, Chromium, Edge, Brave).
• For video, ffmpeg.
• For the Blender add-on, Blender 4.2 or newer (the film of a run: checked in Blender 5.2); for the NetLogo bridge, NetLogo 6 or 7 (the extension: NetLogo 7, and NetLogo 3D 7).
• For CAD, FreeCAD 1.0 or newer (STEP needs nothing more); for game engines, any glTF 2.0 importer (glued joints and worlds as game maps: tested in Godot 4.7). FBX and USD come through Blender.
• For Hermes, the Construct plugin needs Hermes 0.22 or newer; a world from a picture in masterpiece mode needs delegation.max_spawn_depth: 2 in Hermes's config (an orchestrator subagent per construct).
• Tested on macOS; review capture on Linux and Windows is untested.

Documentation

If you want to…	read
see everything new in 1.3, the worlds one by one	What's new in 1.3
make a world, in Hermes or by hand, and the format	Worlds, step by step and Worlds
see how a world was made from one picture	Rain Harbour and Stortorget
use constructs and whole levels in a game	Construct for game developers
see everything new in 1.2, with examples	What's new in 1.2
see everything new in 1.1, with examples	What's new in 1.1
see how a construct is made, step by step	How a construct is made
know what you are looking at, and the keys	The Measured Light style
run it every way, from a first construct by hand to Claude Code and Hermes	Using Construct
fix something that went wrong	Troubleshooting
start from a ready-made template (a book, a CD, a guitar, a car)	Archetypes
make mountains, routes and planets from real elevation data	Terrain
turn a construct into a film with music	Film mode
export a 3D model or a world, plain or finished from its own material map	3D export and the Blender add-on
print it, or make it a model kit	3D printing and kits
open it in CAD	FreeCAD and STEP
put it in a game engine	Godot
draw a NetLogo model's run	The NetLogo bridge and the extension
teach with it, or show it in a museum	In a classroom and a museum
compare models, or score your own	Evaluation
build on it or test the code	Development and the scene contract
write your own adapter (a format, an engine, a machine)	Adapters
use it in Hermes, from the request to a printable kit	Villa Savoye in Hermes, step by step and Construct for Hermes
design something new from real things (a ship, a creature, a vehicle)	New things from real ones
design a physical product from a system's documentation	Documentation → product
see how reconstructing, modifying and inventing are one pipeline	The design-freedom continuum
know where the method comes from	About
see what changed	CHANGELOG.md and the 1.3.0, 1.2.0, 1.1.0 and 1.0.0 release notes

The full index is in docs/README.md.

Contributing

See CONTRIBUTING.md. Run the tests with python3 -m unittest discover -s construct_hologram -t . -p 'test_*.py'. Security reports: SECURITY.md.

License

Apache-2.0 — Copyright (c) 2026 Artyom Andreyev (see NOTICE); versions up to 0.3.0 were MIT. The NetLogo example folders (examples/netlogo-*: viral marketing, flocking, wolf sheep, fire, fireflies, virus on a network and virus compare) derive from Uri Wilensky's NetLogo models and are under CC BY-NC-SA 3.0 instead (see each LICENSE). The Stortorget world, made from a CC BY-SA 4.0 photograph that it includes, is under CC BY-SA 4.0 (see its LICENSE). The Blender add-on is under GPL-3.0-or-later, as Blender's extensions platform requires; what you make with it is yours.

Construct's working method is inspired by Anatomy's truth-first construction (MIT); it shares the method, not code. Product, vehicle and place names in the examples belong to their owners: each example is an independent reconstruction from public references, not an official model. See NOTICE.