OnlyWorlds for ChatGPT

com.onlyworlds/mcp

Read and write typed fictional worlds (22 linked element types) via the OnlyWorlds open standard.

client:ChatGPT transport:streamable-http tools:11

Install OnlyWorlds in ChatGPT

Settings → Connectors → Advanced → Developer mode

https://www.onlyworlds.com/mcp

Custom connectors are a paid-plan feature and take a remote URL only. ChatGPT cannot run a packaged server locally. ChatGPT docs