diff --git a/src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/wwwroot/js/monaco-init.js b/src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/wwwroot/js/monaco-init.js
index 68935d71..ed8710f7 100644
--- a/src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/wwwroot/js/monaco-init.js
+++ b/src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/wwwroot/js/monaco-init.js
@@ -21,9 +21,127 @@
         return readyPromise;
     }
 
-    // Task 9 fills these in (Roslyn-backed providers + real diagnostics fetch).
-    function registerCSharpProviders() { }
-    async function fetchDiagnostics(model) { return []; }
+    const KIND_MAP = { Method: 0, Field: 4, Property: 9, Event: 10, Class: 6, Module: 8, Variable: 4, Text: 18 };
+
+    function registerCSharpProviders() {
+        monaco.languages.registerCompletionItemProvider("csharp", {
+            triggerCharacters: [".", "(", "\""],
+            provideCompletionItems: async function (model, position) {
+                try {
+                    const resp = await fetch("/api/script-analysis/completions", {
+                        method: "POST", credentials: "same-origin",
+                        headers: { "Content-Type": "application/json" },
+                        body: JSON.stringify({ codeText: model.getValue(), line: position.lineNumber, column: position.column })
+                    });
+                    if (!resp.ok) return { suggestions: [] };
+                    const data = await resp.json();
+                    const word = model.getWordUntilPosition(position);
+                    const range = {
+                        startLineNumber: position.lineNumber, endLineNumber: position.lineNumber,
+                        startColumn: word.startColumn, endColumn: word.endColumn
+                    };
+                    return {
+                        suggestions: (data.items || []).map(function (it) {
+                            return {
+                                label: it.label, insertText: it.insertText, detail: it.detail,
+                                kind: KIND_MAP[it.kind] != null ? KIND_MAP[it.kind] : 18,
+                                range: range
+                            };
+                        })
+                    };
+                } catch (e) { return { suggestions: [] }; }
+            }
+        });
+        monaco.languages.registerHoverProvider("csharp", {
+            provideHover: async function (model, position) {
+                try {
+                    const resp = await fetch("/api/script-analysis/hover", {
+                        method: "POST", credentials: "same-origin",
+                        headers: { "Content-Type": "application/json" },
+                        body: JSON.stringify({ codeText: model.getValue(), line: position.lineNumber, column: position.column })
+                    });
+                    if (!resp.ok) return null;
+                    const data = await resp.json();
+                    if (!data.markdown) return null;
+                    return { contents: [{ value: data.markdown }] };
+                } catch (e) { return null; }
+            }
+        });
+        monaco.languages.registerDocumentFormattingEditProvider("csharp", {
+            provideDocumentFormattingEdits: async function (model) {
+                try {
+                    const resp = await fetch("/api/script-analysis/format", {
+                        method: "POST", credentials: "same-origin",
+                        headers: { "Content-Type": "application/json" },
+                        body: JSON.stringify({ code: model.getValue() })
+                    });
+                    if (!resp.ok) return [];
+                    const data = await resp.json();
+                    if (typeof data.code !== "string" || data.code === model.getValue()) return [];
+                    return [{ range: model.getFullModelRange(), text: data.code }];
+                } catch (e) { return []; }
+            }
+        });
+        monaco.languages.registerInlayHintsProvider("csharp", {
+            provideInlayHints: async function (model) {
+                try {
+                    const resp = await fetch("/api/script-analysis/inlay-hints", {
+                        method: "POST", credentials: "same-origin",
+                        headers: { "Content-Type": "application/json" },
+                        body: JSON.stringify({ code: model.getValue() })
+                    });
+                    if (!resp.ok) return { hints: [], dispose: function () {} };
+                    const data = await resp.json();
+                    return {
+                        hints: (data.hints || []).map(function (h) {
+                            return { position: { lineNumber: h.line, column: h.column }, label: h.label, kind: 2, paddingRight: true };
+                        }),
+                        dispose: function () {}
+                    };
+                } catch (e) { return { hints: [], dispose: function () {} }; }
+            }
+        });
+        monaco.languages.registerSignatureHelpProvider("csharp", {
+            signatureHelpTriggerCharacters: ["(", ","],
+            signatureHelpRetriggerCharacters: [","],
+            provideSignatureHelp: async function (model, position) {
+                try {
+                    const resp = await fetch("/api/script-analysis/signature-help", {
+                        method: "POST", credentials: "same-origin",
+                        headers: { "Content-Type": "application/json" },
+                        body: JSON.stringify({ codeText: model.getValue(), line: position.lineNumber, column: position.column })
+                    });
+                    if (!resp.ok) return null;
+                    const data = await resp.json();
+                    if (!data.label) return null;
+                    return {
+                        value: {
+                            signatures: [{
+                                label: data.label,
+                                parameters: (data.parameters || []).map(function (p) { return { label: p.label, documentation: p.documentation }; })
+                            }],
+                            activeSignature: 0,
+                            activeParameter: data.activeParameter || 0
+                        },
+                        dispose: function () {}
+                    };
+                } catch (e) { return null; }
+            }
+        });
+    }
+
+    async function fetchDiagnostics(model) {
+        try {
+            const resp = await fetch("/api/script-analysis/diagnostics", {
+                method: "POST", credentials: "same-origin",
+                headers: { "Content-Type": "application/json" },
+                body: JSON.stringify({ code: model.getValue() })
+            });
+            if (!resp.ok) return [];
+            const data = await resp.json();
+            return data.markers || [];
+        } catch (e) { return []; }
+    }
 
     async function createEditor(id, host, options, dotNetRef) {
         await ensureLoaded();