OpenRP Turned 1! Introducing the Behavior System, Free LLM Promo, and World Simulation Roadmap!

Hello fellow roleplayers!

OpenRP just turned 1 year old! And we are releasing something exciting to celebrate.

The Behavior Engine is now live.

What is the Behavior Engine?

A Behavior is a visual, node-based pipeline for characters that defines exactly how they act and respond.

Our existing prompt system was powerful, but it was fixed. It collected character and chat data, assembled a prompt, called AI, and sent the reply. You could customize the prompt. But you could not change this pipeline.

With Behaviors, this pipeline is now visible and editable. Each step is now a node for you to play with.

Want to send a different prompt to LLM based on a condition? Add conditional branching. Want to make sure the generated response is in-character? Add a loop with an LLM node to check the output before sending. Want to get structured response from AI, send the generated message to your Discord bot, or just roll a dice? Behavior Engine got you covered.

We are building a foundation for roleplay AI where characters truly are aware of their surroundings, interact with each other, and evolve over time.

What can Behaviors do today?

The Behavior Editor today fully replicates our legacy prompt system. It includes nodes for:

• Calling LLMs
• Reading chats, characters, lore
• Conditions, loops, parallel branches
• HTTP requests for connecting a behavior to an outside service

The result is a visual editor for designing agent behavior pipeline end to end, designed specifically for roleplay.

How to start using Behaviors

We published our upgraded chat Behavior at openrp/behaviors/chat. This is now the default for new worlds.

If you want to try this in your existing world, attach this to a character by adding it to your character on the character details page using the published Behavior name: openrp/behaviors/chat.

Once attached, it will use this Behavior when you send a chat message. You may inspect the message metadata for your sent message to peek how it works under the hood.

To use this for all characters, create a new Character Group for all your characters, then attach this Behavior to the group.

To customize or create your own Behaviors, check out the Getting Started guide in our brand new doc site!

I haven't created a world yet. Can I still try this?

Absolutely. You can make a clone your favorite world, and do the steps above.

You can also try Behaviors made by our community. For example, kirisu/test/image-gen-1-0 extends chat with image-generation logic.

It adds a scene-extraction pass, sends an external generation request, and attaches generated images to the character’s messages. That kind of multi-step flow simply was not possible to express in the old prompt system.

Note that cloned worlds will not receive any updates when the original creator updates their world.

For creators: take it apart

The most fun path is to start with something that already works.

Open the Chat behavior, choose Export JSON on the top right menu, then create a Behavior in your own world and paste that graph into Import Graph JSON. Now you have your own copy to experiment with node by node.

The Getting Started guide walks through a smaller chat behavior from scratch, including how to test it and inspect its execution.

And this is not only about OpenRP-made templates. The registry supports community-made Behaviors, where you can learn from each other. We cannot wait to see what the community builds next.

This is only the beginning

Behaviors are tied to chat now because this is the primary way everyone interacts with the characters. But the system is designed for so much more.

Next: Group Chat. The next major feature will be powered by Behaviors. Instead of hard-coding who responds and when, we can make that decision part of the character logic itself.

Then: world instances and storage. Characters will be able to read and mutate world state backed by our database. Think memories that evolve, relationship and affection levels, HP, inventory, quest progress, locations, and world events that actually matter later.

Later: 24/7 world simulation. Characters and worlds that can continue to run beyond the moment you send a message. They will be able to talk to each other, generate and react to events, write new memories, and influence the world around them.

That is the future Behaviors unlock: not merely characters that answer when you send a message, but your personal world sandbox simulated by AI.

A week to experiment

To celebrate the launch, we are giving FREE access to the new GLM 5.3 Flash (known as the OX Alpha) at 16k context for a week.

We have also added GLM 5.3, Grok 4.6, Opus 5 and Sonnet 5 to our model list.

Thank you to everyone who has chatted, created worlds, shared feedback, reported bugs, supported the platform, and helped make this community what it is. A year ago, this was an idea we cared deeply about. Today, we are handing creators the tools to help define what OpenRP becomes next.

Come show us what you build in the OpenRP Discord. We’ll be there to talk Behaviors, trade ideas, debug graphs, and see where this goes together.