feat: readme

src/Lean/Server/README.md

@@ -0,0 +1,23 @@
+## Logging LSP requests
+
+### In `bash`:
+
+```
+mkfifo pipe
+nc -l -p 12345 < pipe | tee client.log | ./build/bin/Server 2> stderr | tee pipe server.log
+```
+will create three files to follow with `tail -f` -- `client.log` for client messages, `server.log` for server messages and `stderr` for server `IO.stderr` debugging
+
+### In VSCode
+
+Set `$extension.trace.server` to `verbose` as described in the *Usage* section of [LSP Inspector](https://microsoft.github.io/language-server-protocol/inspector/).
+
+An easy way to get an LSP client is to build the [sample extension](https://github.com/Microsoft/vscode-extension-samples/tree/master/lsp-sample) and replace the server options in `extension.ts`:
+
+```typescript
+  let serverOptions: ServerOptions = {
+    command: "/usr/bin/nc",
+    args: ["localhost", "12345"],
+    options: null
+  };
+```