About SpecCraft

SpecCraft is an infinite-canvas tool for writing specs and designing systems visually. What makes it different is the built-in AI agent: instead of dragging every box yourself, you describe what you want and the agent manipulates the canvas directly — creating concepts, drawing relations, and laying everything out through tool calls. The result is a diagram you shaped in conversation, with you reviewing every change.

How it works

1. 01

   Open a canvas

   Start from an empty infinite canvas — no sign-up. Bring your own Anthropic API key, which stays in your browser.

2. 02

   Describe what you want

   Tell the AI agent what to build in plain language — "map the services behind checkout", "lay out the onboarding flow". The agent works through tool calls against the canvas.

3. 03

   Review proposals

   The agent adds concepts, draws connectors, and arranges them as proposals you can accept or reject — you stay in control of the final diagram.

4. 04

   Refine and share

   Drag, recolor, and connect by hand; canvases persist server-side and sync live, so collaborators see changes as they happen.

Who it's for

Engineers, product designers, and anyone who thinks in boxes and arrows. SpecCraft is well suited to:

• →Software architecture & system design diagrams
• →Product specs and feature planning
• →Domain models and concept maps
• →Flowcharts and process maps
• →Whiteboarding sessions with an AI collaborator

Open source & built by

SpecCraft is open source — you can read the code, self-host, or contribute on GitHub. It is built and maintained by Oleksandr Zalizniak.