README.md

Repl.Mcp.AspNetCore

ASP.NET Core Streamable HTTP hosting integration for Repl MCP servers.

Hosted in ASP.NET Core

builder.Services.AddReplMcpHttp(replApp);

var app = builder.Build();
app.MapReplMcp("/mcp");

MapReplMcp() maps the default /mcp endpoint.

Use ASP.NET Core middleware and endpoint conventions for production concerns such as authentication, authorization, CORS, HTTPS, and reverse proxy hosting.

builder.Services.AddAuthentication();
builder.Services.AddAuthorization();
builder.Services.AddReplMcpHttp(replApp);

var app = builder.Build();
app.UseAuthentication();
app.UseAuthorization();
app.MapReplMcp("/mcp").RequireAuthorization();

For per-installation transport customization, configure the hosted transport:

builder.Services.AddReplMcpHttp(replApp, http =>
{
	http.IdleTimeout = TimeSpan.FromMinutes(15);
	http.MaxIdleSessionCount = 50;
});

Self-Hosted CLI

Register the local HTTP command on a Repl app:

var replApp = ReplApp.Create()
	.UseMcpHttpServer();

Then run:

myapp mcp httpserve

The default endpoint is http://127.0.0.1:7375/mcp. The port digits map to repl on a phone keypad. The self-hosted command is intended for local agents and trusted development networks. Non-loopback bindings require an explicit opt-in:

myapp mcp httpserve --host 0.0.0.0 --allow-remote

Loopback self-hosting rejects browser requests with unexpected Origin headers and restricts the HTTP Host header to loopback names. Remote opt-in relaxes the Host restriction for trusted networks, but does not add authentication or TLS. Use hosted ASP.NET Core when the endpoint needs production-grade auth, certificates, reverse proxy integration, or custom network policy.

Self-hosted apps can expose limited advanced hooks:

var replApp = ReplApp.Create()
	.UseMcpHttpServer(options =>
	{
		options.ConfigureBuilder = builder =>
			builder.Configuration.AddEnvironmentVariables("MYAPP_");

		options.ConfigureApp = app =>
			app.UseForwardedHeaders();
	});

The http and http-serve aliases also resolve to httpserve.