Core vs full: designing the Fibe CLI and MCP tool surface
The Fibe SDK is one Go binary doing two jobs. Type fibe playgrounds list and it's a normal Cobra CLI. Run fibe mcp serve and the same binary becomes a Model Context Protocol server, so an AI agent — Claude, Codex, Cursor, whoever — can drive your Marquee without paying the fork-and-exec cost of shelling out to the CLI on every operation.
That second job came with a problem we didn't appreciate until we watched agents fail at it. A platform like Fibe has a lot of capabilities: provision a Marquee, launch a Playground, connect a repo through Props, start a Genie agent chat, read logs, manage secrets, fund a wallet. Expose every one as a native MCP tool and you hand the agent a menu with hundreds of items — which, counterintuitively, makes the agent worse. So we split the surface into tiers, where "hidden" never means "gone."