Host mcp server with ASP.NET Core: streamed responses

Deploy a mcp server built with ASP.NET Core on Ample using the streaming response service pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL. Verified on ASP.NET Core: a Server-Sent Events endpoint read incrementally through the public HTTPS gateway: five one-second chunks arrived spread over time with the first within seconds (not buffered), a 70-second stream of 36 chunks completed past common 60-second idle timeouts, and a client that disconnected after two chunks was observed and recorded by the server (disconnected=true). Not separately tested: your event schema, reconnection strategy and any per-request duration ceiling beyond the 70 seconds measured; treat the mcp server-specific behavior as your application code.

Prerequisites

• A ASP.NET Core project that builds and starts with the documented commands (dotnet publish -c Release -o out in the builder, then dotnet .dll on the dotnet-10 template with ASPNETCORE_URLS bound to PORT)
• A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env)
• An Ample account token with servers:write, databases:read

Workflow Steps

1. Build and start
   dotnet publish -c Release -o out in the builder, then dotnet .dll on the dotnet-10 template with ASPNETCORE_URLS bound to PORT. The server must bind 0.0.0.0 on PORT.

2. Implement the pattern on PostgreSQL
   The fixture's module implements streaming response service: a Server-Sent Events endpoint read incrementally through the public HTTPS gateway: five one-second chunks arrived spread over time with the first within seconds (not buffered), a 70-second stream of 36 chunks completed past common 60-second idle timeouts, and a client that disconnected after two chunks was observed and recorded by the server (disconnected=true). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.

3. Deploy
   Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op.

   ample deploy . --name  --public
   

4. Verify
   Fetch the live URL and the pattern self-test route(s) (/p/streaming-response-service) from the example; then run your own checks. On failure read ample logs --kind build then --kind runtime.

   ample logs --kind build
   

Tested Configuration

• Template: dotnet-10
• Runtime: dotnet
• Size: s-1vcpu-1gb
• Build: dotnet publish -c Release -o out
• Start: ASPNETCORE_URLS=http://0.0.0.0:$PORT dotnet out/$(basename $(ls out/*.runtimeconfig.json | head -n 1) .runtimeconfig.json).dll

Success Checks

• App responds on its public URL

  • Kind: http_get
  • Path: /
  • Expect: ample canary asp net core patterns

• Streaming-response-service self-test

  • Kind: http_get
  • Path: /p/streaming-response-service
  • Expect: an SSE stream: data: id=, then chunk events one interval apart (read incrementally: first chunk within seconds, chunks spread over the interval), then data: done; /status?id= reports sent=N disconnected=true|false done=true|false.