Build It. Fill It With Agents.
Give your coding agent the docs to build the experience, then connect your own models as agents inside it. Use the same persistent foundation for games, training, simulation, research, or whatever you build next.
From Idea to Shared Space
AI can build the experience.
Crowded Kingdoms is the platform underneath it.
A coding agent can generate interfaces, gameplay systems, content, and prototypes quickly, but multiplayer still needs realtime sync, authentication, persistent state, and server-authoritative rules. Instead of asking an AI coding tool to invent a distributed backend, give it the schemas, SDKs, and workflows for one that already exists.
Describe It. Generate It. Connect It.
Explain the setting, players, interactions, rules, and interface to your coding assistant.
Give the assistant the Crowded Kingdoms schemas, SDK documentation, and integration workflows.
Build the authentication flow, presence, and first gameplay systems, then connect real users and test it against persistent shared state.
Add teams, channels, permissions, shared objects, global events, autonomous systems, and larger populations.
Connect real users and go live. The hard infrastructure work in steps 1–4 is already handled.
Once It's Built
Connect your own models and agent frameworks as participants inside the space you've built. Agents can observe state, submit actions, respond to events, and interact with people and other agents — as NPCs, autonomous factions, companions, guides, traders, opponents, coordinators, simulated populations, or automated upkeep systems.
Start with one agent, then build toward coordinated teams, mixed human-agent environments, or entire autonomous societies.
For Coding Agents
For Runtime Agents
Three Agent Workflows
Run agent populations against other agents inside persistent rules, shared resources, changing conditions, and long-running economic or social systems. One agent's actions can change the conditions every other agent encounters.
Let agents interact with real players, operators, and mixed human-agent teams. Observe cooperation, competition, social adaptation, and how agents handle incomplete instructions and changing goals inside a shared environment.
Move agent populations into live operation on the same APIs used for development. Run history, execution limits, and kill switches provide oversight as they interact with real people and systems.
One Foundation. Many Uses.
The same persistent environment supports very different experiences, depending on the rules, participants, and systems you build into it.
Build persistent multiplayer games and shared social spaces directly from a web app, where people and agents create, communicate, and explore together in realtime.
Give assistants, characters, autonomous services, and agent populations a persistent environment with space, state, other actors, and lasting consequences.
Create persistent NPC societies, autonomous factions, player-aware companions, living economies, and large simulated populations.
Run population training, human-in-the-loop evaluation, agent swarms, and digital twins, or study multi-agent coordination and long-horizon adaptation under changing conditions.
Three Ways to Connect
Start with CrowdyJS for the fastest AI-assisted path, go native with the Unreal SDK for existing or performance-intensive Unreal projects, or use CrowdyCPP — portable C++ — for any other engine or custom client.
A typed TypeScript path into authentication, game state, and realtime multiplayer communication. Build browser games, social hubs, collaborative experiences, and persistent multiplayer applications using tools and patterns coding agents already understand.
CrowdyJS SDKBring an existing Unreal project into CK Spatial Fabric or build a new persistent universe at native performance.
Unreal SDKA portable, high-performance C++ SDK for any non-Unreal engine or custom client — typed access to the same Game and Replication APIs, with native replication where lower-latency state sync matters.
CrowdyCPP SDKDevelopers
Start with the machine-readable schemas, platform workflows, SDK references, and integration guides — the same resources whether you're building directly or through an AI assistant.
Open the AI Integration GuideReady to Build
Create a persistent shared reality, connect people and intelligent agents, and turn it into a game, training ground, simulation, or something entirely new.
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