Free Browser Tool Lets You Sketch Robot Behavior Without Installing Anything

Imagine you're building a robot that needs to decide: should I go forward, turn, or stop? A behavior tree is like a flowchart that helps robots make those decisions. But designing one usually requires special software that you have to install. Now, a developer has created behaviortrees.com, a free website that lets you draw and edit behavior trees right in your browser. No downloads, no installations—just open the page and start sketching.

The tool is especially useful for people working with Nav2, a popular navigation system for robots. It can import and export files in the format used by BehaviorTree.CPP, the programming library that many robots use. That means you can design a tree in the browser and then use it in your actual robot code. The creator has even set up automatic tests to make sure the exported files work correctly with the real library. It's meant to complement Groot2, the official editor, not replace it—so it's great for quick sketches, reviews, or sharing ideas.

One of the best features is that you can share a link that contains the entire tree. So if you're discussing a robot's behavior in a GitHub issue or a pull request, you can just drop a link and anyone can see exactly what you mean. That makes collaboration much easier, especially for remote teams or open-source projects. The creator is now asking for feedback from Nav2 users: what's missing, and which trees don't round-trip cleanly (meaning they don't export and re-import perfectly)? This will help improve the tool for everyone.