Duck draws with the same commands you do.
Duck is the assistant in Linework. It doesn’t operate the interface; it calls the commands you type too. You see every step in the command line, and one undo takes the whole run back.
Click to draw. Scroll zooms after the first click.
Press / anywhere on this page to type a command.
This is not a video but a small CAD in the browser. Duck turns the floor plan into a model and checks a door, with commands that exist in Linework. Then you draw. In the app, Duck works on the whole building model.
How Duck works
Tools are commands
354 of the 365 commands are open to Duck. A new command is a tool without anything more being done, from drawing a wall to the heat load.
wallsectionheatloadnetcheckRead first, then draw
Duck queries the drawing selectively, filtered by layer, type, area or ids, and can look at a picture of the view to check what came out.
get_drawinglook_at_viewOnly its own steps
Duck sets checkpoints and takes back what it did itself, never your work. A button beneath the answer undoes the whole run.
checkpointundo_mineFiles stay with you
Duck may save the drawing it works on and put a copy beside it. Opening, importing, plotting and overwriting are closed to it.
save_drawingSkills
A skill is a text file with steps, permitted commands and checks, for a permit plan set or an as-built model from a drawn floor plan, say. Duck follows it and can write new ones.
skill
What goes to Anthropic
Duck uses Claude from Anthropic, model Claude Opus 5.5, with your own API key. The app talks to the API directly; no server of ours sits in between.
- Your question and the course of the conversation
- What Duck queries from the drawing: objects with ids, types, layers, points, texts and attribute values
- The file path of the drawing
- Pictures of the view when Duck looks
The file as a whole is not uploaded. The key is stored in the macOS keychain, and use is billed to your account with Anthropic.
Duck is an offer. Without a key the tab stays empty, and everything else in Linework works as before.
Agents in the open drawing
Claude Code and other agents connect to the running app over MCP and work in the drawing that is open. You watch every step appear.
Local
The server listens on your machine only (127.0.0.1) and is off by default. You switch it on in the Duck tab. It turns away requests from web pages.
The same tools
Every command Duck has, plus a screenshot of the view, setting the view and the position of your pointer. Skills show up as prompts.
No key in the app
The agent brings its own model. In a team it is visible as a participant with a name.
Run once in a terminal:
claude mcp add --transport http framemind-linework http://127.0.0.1:7781/mcpOther CAD programs have MCP by now too. What differs in Linework: every command is a tool, the server runs on your machine, and you watch live.
Without a window
linework-cli runs any command from a script or a build job and exports PDF, DWG, DXF, IFC or SVG. That is how the example projects on this site are built.
linework-cli --json box '{"corner": [0, 0, 0], "size": [10, 20, 30]}' --export box.svgFour lines from the town hall’s script, as it sends them to Linework:
units {"units": "m"}
dimstyle {"name": "Plan", "ends": "tick", "decimals": 2, "separator": ",", "din1356": true, "current": true}
elecdoc {"paper": "A1", "scale": 50, "layerState": "Elektro", "language": "de"}
sheetlist {"place": [20, 280, 0], "language": "de"}
Download Linework and open one of your drawings.
The app is free, for professional work too, without an account or a licence key.
- Product
- FrameMind Linework
- Version
- 0.19.2
- Date
- 13 November 2026
- Platform
- macOS, Apple silicon
- Windows
- in preparation
- Price
- free