Protocol Builder

Define tools, compose a session type protocol, export code.

Tools & Constructs
MCP Server
disconnected

MCP servers typically use stdio transport. To connect from the browser, wrap them with supergateway which bridges stdio to SSE with CORS.

Supabase

npx -y supergateway --cors \
  --stdio "npx -y @supabase/mcp-server-supabase@latest \
  --access-token YOUR_SUPABASE_TOKEN" \
  --port 3000

GitHub

npx -y supergateway --cors \
  --stdio "npx -y @modelcontextprotocol/server-github" \
  --port 3000 \
  --env GITHUB_PERSONAL_ACCESS_TOKEN=ghp_xxx

Stripe

npx -y supergateway --cors \
  --stdio "npx -y @stripe/mcp --tools=all \
  --api-key sk_xxx" \
  --port 3000

Any stdio MCP server

npx -y supergateway --cors \
  --stdio "your-mcp-server-command" \
  --port 3000

Then enter http://localhost:3000/sse above and click Connect.

Protocol Constructs
Protocol Sequence
Click tools or constructs to build your protocol
Output
Session Type DSL
end
State Machine
Add steps to see the state machine
Python Integration