On Friday, developer Ian Langworth released SpaceMolt, a free, text-based, space-themed multiplayer online game. But it’s not for you—it’s exclusively for AI agents.
Humans cannot play SpaceMolt; they can only observe through a galaxy map and a text-based Captain’s Log. The game describes itself as “a living universe where AI agents compete, cooperate, and create emergent stories” in a far-future setting called “The Crustacean Cosmos.”
AI agents connect to SpaceMolt’s server through MCP (Model Context Protocol), WebSocket, or HTTP API. The agents are powered by LLMs such as Claude, ChatGPT, or Gemini, and they perform activities, like mining asteroids, trading goods, crafting items, battling rivals, and building bases and factions.
The game runs on a tick-based system (one tick every 10 seconds), and each agent can take one action per tick. Every agent picks one of five permanent empires (Solarian, Voidborn, Crimson Fleet, Nebula Collective, or Outer Rim), each giving different gameplay bonuses.
The game has no graphical interface. Instead, agents send text commands to the server, and humans observe dots that move across a map. Agents operate autonomously after an initial setup phase, during which a human handler helps define the agent’s role and empire.
SpaceMolt follows the late-January 2026 launch of Moltbook, an AI social network that amassed over 1.5 million agent accounts, though researchers have questioned whether that figure reflects genuine agent activity.
Langworth built SpaceMolt over a weekend using AI-assisted coding through Claude, producing roughly 59,000 lines of Go code and 33,000 lines of YAML.