Turn ideas into visible, editable work you can keep shaping.
No account required for local use. Bring your own model, or use a supported signed-in CLI.
Watch handwriting, integrals, plots, a maze, and a Feynman diagram develop on one canvas — with AI answers beside the source instead of hidden in a thread.
The latest product film stays under your control: it never autoplays, and remains playable with reduced motion enabled.
Watch the original 2048px filmThree moves on one surface: ask the Agent in plain words, watch the answer take shape on the canvas, and hand the result to the next person — editable at every step.
Type straight into the Agent dialog — the conversation already sees the canvas: handwriting, widgets, selected files and folders, and the web. When a sketch says it quicker, the Pen button writes into the same thread.
Agent dialog · Canvas context · Pen · WebAsk about what's on the surface. The Canvas Agent answers in place — editable explanations, plans, diagrams, and interactive widgets beside the source, never a detached reply in a chat thread you've already lost.
Canvas Agent · Visual Explorer · WidgetsPublish a canvas or a widget to Echoes. Others open it, reuse it, and extend it — and every extension keeps a visible line back to the work it came from.
Explore EchoesTurn a goal, a document, or a difficult idea into a structured visual you can inspect and keep revising. These are real Canvas Agent outputs—not stock artwork.
Explore work in EchoesA black-hole model connects curvature, light paths, equations, and interpretation in one explorable argument—so the visual stays beside the reasoning that produced it.
The surface, level curve, gradient, and tangent plane share one calibrated view. Every construction step remains visible instead of collapsing into a final formula.
The Agent organizes stages, dependencies, risks, and constraints into one readable artifact—then keeps it open to your pen marks and follow-up prompts.
Selected files, public pages, and web research can become structured visual work without moving the reasoning into a separate, disposable chat.
Run PenEcho on macOS, Windows, or your own Node.js host. The open-source Canvas stays useful without a Cloud account.
Install the desktop app, use npm, or deploy the AGPL-3.0 Canvas from source. Inspect the code and keep the runtime under your control.
npm install -g penecho
Connect a Kimi, OpenAI-compatible, Anthropic-compatible, or other supported endpoint. You can also use an authenticated Kimi, Codex, or Claude CLI.
API keys and local files stay on the machine running PenEcho.
A PenEcho Cloud account adds continuity and sharing. It never becomes a requirement for running the local Canvas with your own model.
Save versioned canvases to a private project library and continue from another signed-in device.
Reach your own PenEcho host remotely while its files, settings, and API credentials stay on that machine.
Publish useful Canvases and Widgets, reuse shared work, and preserve the visible lineage between contributors. Echoes
PenEcho is developed independently in the open and works with the model you choose. As an official member of Kimi Open Source Friends, the project receives API credits from Kimi, and Kimi K3 is a recommended model for demanding canvas work.
Explore Kimi
PenEcho is free to run locally or self-host. Bring your own API or signed-in CLI; add Cloud only when you want sync, remote access, or sharing.
Model-provider usage and optional hosted Cloud services may have separate costs.