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Compose servers from smaller ones: mount() mirrors an in-process child into a parent, and createProxy() wraps a remote MCP server as a mountable FastMCP instance. 
import { FastMCP, createProxy } from '@prefecthq/fastmcp-ts/server'

const weather = new FastMCP({ name: 'weather' })
const maps = await createProxy({ type: 'http', url: 'http://maps-service/mcp' })

const gateway = new FastMCP({ name: 'gateway' })
gateway.mount(weather, 'weather')   // → weather_forecast
gateway.mount(maps, 'maps')         // → maps_<tool_name>
This page is under construction. The outline below sketches what it will cover.
  • Mounting semantics — live mirroring (components registered on the child after mount() appear in the parent immediately, with list_changed notifications); prefixing renames tools/prompts to ${prefix}_${name} but never alters resource URIs; mounting cascades through grandparent chains.
  • Why it composes cleanly — mounted components land in the parent’s own registries, so transforms, middleware, and auth apply to them identically.
  • Proxying — createProxy({ type: 'stdio' | 'http', ... }) returns a plain FastMCP that forwards all calls verbatim; closing the parent closes the proxied connection.
  • Choosing between mount and proxy — in-process vs. remote, and combining both behind one gateway.