fairies

The Spatial Harness: Bringing Agents to the Canvas — Max Drake, tldraw

Sep 10, 2026 · 18:52

Max Drake, product engineer at London's tldraw, argues coding agents excel because code is text in and text out, while canvas agents need engineering to understand and act in 2D space. tldraw, the whiteboard app and SDK behind canvases including Replit's, ships an MIT-licensed agent starter kit that teaches models to read a canvas from screenshot plus JSON and set their own todos, moving their viewport to explore. Fairies renders agents as figures you can throw and recolor; selecting several opens a group chat with an orchestrator assigning and reviewing work — you read ten agents' state at a glance, not a chat log. Last, a dependency graph of coding agents and a desktop build that lets agents script the editor — a colleague made it a window manager playing Pong with real windows.

Agents on the Canvas in tldraw — Steve Ruiz, tldraw

May 1, 2026 · 19:54

Steve Ruiz of tldraw details the evolution of AI on the infinite canvas, from early one-shot demos like MakeReal (draw to functional prototype) to multi-agent 'fairies' that collaborate, delegate, and even rewrite the canvas in real time. He explains how the tldraw SDK enables agents to act as virtual collaborators, using structured outputs and tool use to draw, animate, and modify designs. Ruiz demonstrates fairy agents that can work independently or in leader-follower mode, coordinating on tasks like creating wireframes or filling out forms. He also unveils a desktop prototype that lets Claude directly inject JavaScript into the canvas, enabling agents to edit code, modify UI, and even hack other apps like Spotify. The talk emphasizes the shift from sidebar agents to canvas-native collaborators, the challenges of vision model training for 2D spaces, and the safety trade-offs of giving LLMs runtime access in local-first apps.