Transports¶

Both native implementations support STDIO and stateless Streamable HTTP.

STDIO¶

STDIO remains the default. The MCP client launches one subprocess for each client session.

./kwp-mcp-go-linux-amd64

Credentials resolve from CLI flags, environment variables, or .env.

Streamable HTTP¶

./kwp-mcp-go-linux-amd64 \
  --transport http \
  --listen-address 127.0.0.1 \
  --port 8082

The C# binary accepts the same transport, address, and port arguments.

Endpoint	Purpose
`/mcp`	Stateless Streamable HTTP MCP
`/health`	Health, service identity, and version metadata
`/shutdown`	Optional manager-authenticated loopback shutdown

--listen-address falls back to MCP_LISTEN_ADDRESS and then 127.0.0.1. --port falls back to PORT and then 8080.

Configure an HTTP-capable client with:

{
  "mcpServers": {
    "keyword-planner": {
      "type": "http",
      "url": "http://127.0.0.1:8082/mcp",
      "tools": ["*"]
    }
  }
}

Credentials belong to the server process, not the HTTP client configuration.

Security defaults¶

The default listener is loopback-only.
Go and C# validate Host headers.
Go and C# reject mismatched browser Origin headers.
MCP request bodies are limited to 1 MiB.
Header and keep-alive timeouts are bounded.
The transport is stateless and requires no session affinity.

Go uses the comma-separated --allowed-hosts option. C# uses standard ASP.NET Core AllowedHosts, whose default is:

localhost;127.0.0.1;[::1]

The built-in host does not authenticate MCP callers. Non-loopback deployments require TLS, authentication and authorization, trusted proxy configuration, and ingress limits.

See Shared Service for cross-session lifecycle management.