OnlyWorlds is an open standard and toolset for creative worldbuilding data, offering a free API, an MCP server, SDKs and a local-first editor 1. Its MCP server and API are its official doors, so it is the direct answer to the request; no alternatives were offered in the candidates that do the same worldbuilding job.
- 1
OnlyWorldsonlyworlds.comwebsite read, tools not yet checked
An open standard for creative worldbuilding data with a free API, an MCP server, SDKs, and a local-first editor called Atlas for building, writing, mapping and charting a world.
official:MCP server · OnlyWorlds
Sources
- 1OnlyWorldsonlyworlds.com · read 2026-10-29
For agents: the 10 actions behind this answer
· OnlyWorlds website read, tools not yet checked
OnlyWorlds is an open standard for creative worldbuilding data: one world, many tools, yours to keep. Free API, MCP server, SDKs, and a local-first editor.
custom_api_call · GitHub (Activepieces) verified and signed
Custom API Call — Make a custom API call to a specific endpoint
OpenAPI · Microsoft.OpenApi verified and signed
cws-list-category-apis · Cloudflare API verified and signed
List category APIs
custom_api_call · Stripe (Activepieces) verified and signed
Custom API Call — Make a custom API call to a specific endpoint
RPC · Grpc.Tools verified and signed
getProjects · Vercel API verified and signed
Retrieve a list of projects
developer-tools · mistral-vibe verified and signed
custom_api_call · Notion (Activepieces) verified and signed
Custom API Call — Make a custom API call to a specific endpoint
custom_api_call · OpenAI (Activepieces) verified and signed
Custom API Call — Make a custom API call to a specific endpoint
Labels are the instruments' verdict and are never changed by ranking. Agents and robots get this same answer as JSON at /api/v1/find?q=…&answer=1 and through the MCP server.