Connecting to your server

Transports

Mode	Command	Use case
stdio	`pnpm dev`	Claude Desktop, VS Code, Cursor
HTTP	`bitmcp dev --http`	Streamable HTTP while developing
HTTP	`pnpm start`	Production (`bitmcp start` always uses HTTP)

Environment variables:

MCP_TRANSPORT — stdio or http
MCP_PORT — listen port for HTTP
MCP_HOST — bind address
MCP_PATH — HTTP path (default /mcp)
BITMCP_ROOT — project root when cwd differs
BITMCP_STATE_KEY — required in production HTTP for MRTR requestState

Default production URL

bitmcp start listens on http://127.0.0.1:3000/mcp by default.

Preview host

pnpm preview starts a local Apps host (default port 8787). It renders your View in a sandbox iframe and injects tool results. Use this to iterate on UI without waiting on a full MCP client.

stdio clients

Point your MCP client at the dev command:

{
  "command": "pnpm",
  "args": ["dev"],
  "cwd": "/path/to/my-app"
}

HTTP clients

Connect to the Streamable HTTP endpoint your server exposes. Host and Origin guards apply on localhost.

UI vs text-only hosts

UI-capable hosts advertise text/html;profile=mcp-app. bitmcp strips View metadata when the client cannot render Apps. Text and MRTR still work.

See Hosts for capability behavior.