diff --git a/Endpoints/ApiKeysEndpoint.cs b/Endpoints/ApiKeysEndpoint.cs
index c935d9c..855d293 100644
--- a/Endpoints/ApiKeysEndpoint.cs
+++ b/Endpoints/ApiKeysEndpoint.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using System.Net.Http;
 using System.Text.Json;
@@ -15,13 +16,14 @@ public static class ApiKeysEndpoint
 {
     public static void MapApiKeysEndpoints(this WebApplication app)
     {
+        // Admin-Endpoints
         app.MapGet("/api/admin/api-keys", HandleGetAll);
         app.MapPost("/api/admin/api-keys", HandleCreate);
         app.MapPut("/api/admin/api-keys/{keyId}", HandleUpdate);
-        app.MapPut("/api/admin/api-keys/{keyId}/activate", HandleActivate);
-        app.MapPut("/api/admin/api-keys/{keyId}/deactivate", HandleDeactivate);
+        app.MapPut("/api/admin/api-keys/{keyId}/public", HandleTogglePublic);
         app.MapDelete("/api/admin/api-keys/{keyId}", HandleDelete);
         app.MapPost("/api/admin/api-keys/{keyId}/check", HandleCheck);
+        app.MapPost("/api/admin/api-keys/check-all", HandleCheckAll);
 
         // Scan-Endpoints
         app.MapPost("/api/admin/api-keys/scan", HandleScanTrigger);
@@ -30,6 +32,11 @@ public static class ApiKeysEndpoint
         app.MapPost("/api/admin/api-keys/scanned/{id}/recheck", HandleRecheck);
         app.MapPost("/api/admin/api-keys/scanned/{id}/adopt", HandleAdopt);
         app.MapDelete("/api/admin/api-keys/scanned/{id}", HandleDeleteScanned);
+
+        // User-Endpoints (für alle authentifizierten User)
+        app.MapGet("/api/api-keys/available", HandleGetAvailable);
+        app.MapPut("/api/api-keys/select/{keyId}", HandleSelectKey);
+        app.MapGet("/api/api-keys/selected", HandleGetSelected);
     }
 
     private static async Task HandleGetAll(HttpContext ctx, DatabaseService db)
@@ -43,7 +50,7 @@ public static class ApiKeysEndpoint
             k.Provider,
             k.Name,
             k.ApiKey,
-            k.IsActive,
+            k.IsPublic,
             k.Status,
             k.Plan,
             k.Usage7d,
@@ -73,13 +80,15 @@ public static class ApiKeysEndpoint
         }
 
         var now = DateTime.UtcNow.ToString("o");
+        var isPublic = body.TryGetProperty("isPublic", out var pub) && pub.GetBoolean();
+
         var record = new ApiKeyRecord
         {
             KeyId = Guid.NewGuid().ToString("N"),
             Provider = provider,
             Name = name,
             ApiKey = apiKey,
-            IsActive = false,
+            IsPublic = isPublic,
             CreatedAt = now,
             UpdatedAt = now
         };
@@ -91,12 +100,12 @@ public static class ApiKeysEndpoint
             record.Provider,
             record.Name,
             record.ApiKey,
-            record.IsActive,
+            record.IsPublic,
             record.CreatedAt
         });
     }
 
-    private static async Task HandleUpdate(HttpContext ctx, DatabaseService db, AnthropicService anthropic, string keyId)
+    private static async Task HandleUpdate(HttpContext ctx, DatabaseService db, string keyId)
     {
         if (!ctx.IsAdmin()) { ctx.Response.StatusCode = 403; return; }
 
@@ -116,15 +125,10 @@ public static class ApiKeysEndpoint
             name = existing.Name;
 
         await db.UpdateApiKey(keyId, name, apiKey);
-
-        // Wenn aktiver Key geändert wird → Token im Service aktualisieren
-        if (existing.IsActive && existing.Provider == "anthropic" && !string.IsNullOrWhiteSpace(apiKey))
-            anthropic.UpdateToken(apiKey);
-
         await ctx.Response.WriteAsJsonAsync(new { ok = true });
     }
 
-    private static async Task HandleActivate(HttpContext ctx, DatabaseService db, AnthropicService anthropic, string keyId)
+    private static async Task HandleTogglePublic(HttpContext ctx, DatabaseService db, string keyId)
     {
         if (!ctx.IsAdmin()) { ctx.Response.StatusCode = 403; return; }
 
@@ -136,16 +140,12 @@ public static class ApiKeysEndpoint
             return;
         }
 
-        await db.SetActiveApiKey(keyId, existing.Provider);
-
-        // Token im laufenden Service aktualisieren
-        if (existing.Provider == "anthropic")
-            anthropic.UpdateToken(existing.ApiKey);
-
-        await ctx.Response.WriteAsJsonAsync(new { ok = true });
+        var newPublic = !existing.IsPublic;
+        await db.SetApiKeyPublic(keyId, newPublic);
+        await ctx.Response.WriteAsJsonAsync(new { ok = true, isPublic = newPublic });
     }
 
-    private static async Task HandleDeactivate(HttpContext ctx, DatabaseService db, AnthropicService anthropic, string keyId)
+    private static async Task HandleDelete(HttpContext ctx, DatabaseService db, string keyId)
     {
         if (!ctx.IsAdmin()) { ctx.Response.StatusCode = 403; return; }
 
@@ -157,31 +157,6 @@ public static class ApiKeysEndpoint
             return;
         }
 
-        await db.DeactivateApiKey(keyId);
-
-        // Token im laufenden Service leeren
-        if (existing.Provider == "anthropic")
-            anthropic.UpdateToken("");
-
-        await ctx.Response.WriteAsJsonAsync(new { ok = true });
-    }
-
-    private static async Task HandleDelete(HttpContext ctx, DatabaseService db, AnthropicService anthropic, string keyId)
-    {
-        if (!ctx.IsAdmin()) { ctx.Response.StatusCode = 403; return; }
-
-        var existing = await db.GetApiKey(keyId);
-        if (existing == null)
-        {
-            ctx.Response.StatusCode = 404;
-            await ctx.Response.WriteAsJsonAsync(new { error = "Key nicht gefunden" });
-            return;
-        }
-
-        // Wenn aktiver Key gelöscht wird → Token leeren
-        if (existing.IsActive && existing.Provider == "anthropic")
-            anthropic.UpdateToken("");
-
         await db.DeleteApiKey(keyId);
         await ctx.Response.WriteAsJsonAsync(new { ok = true });
     }
@@ -226,6 +201,25 @@ public static class ApiKeysEndpoint
         });
     }
 
+    private static async Task HandleCheckAll(HttpContext ctx, IHttpClientFactory httpFactory, DatabaseService db)
+    {
+        if (!ctx.IsAdmin()) { ctx.Response.StatusCode = 403; return; }
+
+        var allKeys = await db.GetApiKeys();
+        var anthropicKeys = allKeys.Where(k => k.Provider == "anthropic").ToList();
+
+        var results = new List<object>();
+        foreach (var key in anthropicKeys)
+        {
+            var result = await AnthropicKeyChecker.CheckKeyAsync(httpFactory, key.ApiKey);
+            var dbStatus = (result.Status == "ok" || result.Status == "usage_limited") ? "valid" : result.Status;
+            await db.UpdateApiKeyMeta(key.KeyId, dbStatus, result.Plan, result.Usage7d, result.Usage5h);
+            results.Add(new { key.KeyId, key.Name, status = dbStatus, result.Plan, result.Usage5h, result.Usage7d });
+        }
+
+        await ctx.Response.WriteAsJsonAsync(new { checked_ = results.Count, results });
+    }
+
     // ── Scan-Endpoints ──
 
     private static Task HandleScanTrigger(HttpContext ctx, KeyScannerService scanner)
@@ -350,7 +344,7 @@ public static class ApiKeysEndpoint
             Provider = "anthropic",
             Name = title,
             ApiKey = sk.ApiKey,
-            IsActive = false,
+            IsPublic = false,
             Status = sk.Status,
             Plan = sk.Plan,
             Usage7d = sk.Usage7d,
@@ -374,4 +368,80 @@ public static class ApiKeysEndpoint
         await ctx.Response.WriteAsJsonAsync(new { ok = true });
     }
 
+    // ── User-Endpoints ──
+
+    private static async Task HandleGetAvailable(HttpContext ctx, DatabaseService db)
+    {
+        var userId = ctx.GetUserId();
+        if (userId == null) { ctx.Response.StatusCode = 401; return; }
+
+        var isAdmin = ctx.IsAdmin();
+        var keys = isAdmin ? await db.GetApiKeys() : await db.GetPublicApiKeys();
+
+        var result = keys.Select(k => new
+        {
+            k.KeyId,
+            k.Provider,
+            k.Name,
+            k.IsPublic,
+            k.Status,
+            k.Plan,
+            k.Usage7d,
+            k.Usage5h,
+            k.CheckedAt
+        });
+        await ctx.Response.WriteAsJsonAsync(result);
+    }
+
+    private static async Task HandleSelectKey(HttpContext ctx, DatabaseService db, string keyId)
+    {
+        var userId = ctx.GetUserId();
+        if (userId == null) { ctx.Response.StatusCode = 401; return; }
+
+        var key = await db.GetApiKey(keyId);
+        if (key == null)
+        {
+            ctx.Response.StatusCode = 404;
+            await ctx.Response.WriteAsJsonAsync(new { error = "Key nicht gefunden" });
+            return;
+        }
+
+        // Nicht-Admins dürfen nur public Keys auswählen
+        if (!ctx.IsAdmin() && !key.IsPublic)
+        {
+            ctx.Response.StatusCode = 403;
+            await ctx.Response.WriteAsJsonAsync(new { error = "Key ist nicht öffentlich" });
+            return;
+        }
+
+        await db.SetUserSelectedApiKey(userId, keyId);
+        await ctx.Response.WriteAsJsonAsync(new { ok = true, keyId, name = key.Name });
+    }
+
+    private static async Task HandleGetSelected(HttpContext ctx, DatabaseService db)
+    {
+        var userId = ctx.GetUserId();
+        if (userId == null) { ctx.Response.StatusCode = 401; return; }
+
+        var key = await db.GetUserSelectedApiKey(userId);
+        if (key == null)
+        {
+            await ctx.Response.WriteAsJsonAsync(new { selected = false });
+            return;
+        }
+
+        await ctx.Response.WriteAsJsonAsync(new
+        {
+            selected = true,
+            keyId = key.KeyId,
+            provider = key.Provider,
+            name = key.Name,
+            isPublic = key.IsPublic,
+            status = key.Status,
+            plan = key.Plan,
+            usage5h = key.Usage5h,
+            usage7d = key.Usage7d
+        });
+    }
+
 }
diff --git a/Endpoints/ChatEndpoint.cs b/Endpoints/ChatEndpoint.cs
index e361010..4bf8513 100644
--- a/Endpoints/ChatEndpoint.cs
+++ b/Endpoints/ChatEndpoint.cs
@@ -51,6 +51,16 @@ public static class ChatEndpoint
         }
 
         var userId = req.HttpContext.GetUserId();
+
+        // API-Key des Users auflösen
+        var userApiKey = await db.GetUserSelectedApiKey(userId);
+        if (userApiKey == null)
+        {
+            res.StatusCode = 400;
+            await res.WriteAsJsonAsync(new { error = "Kein API-Key ausgewählt. Bitte wähle einen Key aus." });
+            return;
+        }
+
         var maxIterations = config.GetValue<int>("MaxIterations", 100);
 
         var hasRemote = remoteMgr.GetBySessionId(sessionId) != null;
@@ -142,7 +152,7 @@ public static class ChatEndpoint
             var preparerHistory = await chatService.BuildHistoryFromDb(sessionId, includeTag: "preparer", promptBlocks: ctx.PromptBlocks);
 
             var preparerResult = await anthropic.RunPreparer(
-                res, ctx.Preparer, preparerHistory, ctx.ChainId, ctx.Workspace, sessionId, cancellationToken);
+                res, ctx.Preparer, preparerHistory, ctx.ChainId, ctx.Workspace, sessionId, userApiKey.ApiKey, cancellationToken);
 
             if (!preparerResult.ShouldForward)
             {
@@ -216,7 +226,7 @@ public static class ChatEndpoint
             else
             {
                 // Standard: Anthropic
-                await anthropic.StreamChat(res, ctx.ModelId, ctx.SystemPrompt, messages, ctx.ChainId, ctx.Workspace, sessionId, agentId: ctx.AgentId, userId: userId, useMemory: ctx.UseMemory, webSearchVersion: ctx.WebSearchVersion, maxIterations: ctx.MaxIterations, toolChoice: effectiveToolChoice, review: ctx.Review, finalizer: ctx.Finalizer, allowUserChoice: ctx.Agent?.AllowUserChoice ?? true, planMode: ctx.PlanMode, useAutoContext: ctx.Agent?.UseAutoContext ?? true, useGitHubSearch: ctx.Agent?.UseGitHubSearch ?? false, useSerperSearch: ctx.Agent?.UseSerperSearch ?? false, workCt: workCt, hardCt: hardCt, sseCt: sseCt, remoteMgr: remoteMgr);
+                await anthropic.StreamChat(res, ctx.ModelId, ctx.SystemPrompt, messages, ctx.ChainId, ctx.Workspace, apiToken: userApiKey.ApiKey, sessionId: sessionId, agentId: ctx.AgentId, userId: userId, useMemory: ctx.UseMemory, webSearchVersion: ctx.WebSearchVersion, maxIterations: ctx.MaxIterations, toolChoice: effectiveToolChoice, review: ctx.Review, finalizer: ctx.Finalizer, allowUserChoice: ctx.Agent?.AllowUserChoice ?? true, planMode: ctx.PlanMode, useAutoContext: ctx.Agent?.UseAutoContext ?? true, useGitHubSearch: ctx.Agent?.UseGitHubSearch ?? false, useSerperSearch: ctx.Agent?.UseSerperSearch ?? false, workCt: workCt, hardCt: hardCt, sseCt: sseCt, remoteMgr: remoteMgr);
             }
         }
         finally
diff --git a/Models/ApiKeyRecord.cs b/Models/ApiKeyRecord.cs
index b7d6b38..7f2b570 100644
--- a/Models/ApiKeyRecord.cs
+++ b/Models/ApiKeyRecord.cs
@@ -7,7 +7,7 @@ public class ApiKeyRecord
     public string Provider { get; set; }     // anthropic, gemini, openai, ...
     public string Name { get; set; }         // Anzeigename z.B. "Tausi Pro Key"
     public string ApiKey { get; set; }       // Der eigentliche Key
-    public bool IsActive { get; set; }       // Nur einer pro Provider aktiv
+    public bool IsPublic { get; set; }       // Für alle User sichtbar/auswählbar
     public string Status { get; set; }       // ok, invalid, rate_limited, quota_exceeded, error
     public string Plan { get; set; }         // Pro, Max, Pro/Max, API Console, Unknown
     public double? Usage7d { get; set; }
diff --git a/Models/ChatContext.cs b/Models/ChatContext.cs
index 2b4804b..ab295a6 100644
--- a/Models/ChatContext.cs
+++ b/Models/ChatContext.cs
@@ -21,6 +21,7 @@ public class ChatContext
     public AgentRecord Agent { get; set; }
     public SessionRecord Session { get; set; }
     public bool PlanMode { get; set; }
+    public string ApiToken { get; set; }
 
     // Preparer-Agent (vor dem Worker)
     public SubAgentContext Preparer { get; set; }
diff --git a/Models/UserRecord.cs b/Models/UserRecord.cs
index 0551834..aab5b66 100644
--- a/Models/UserRecord.cs
+++ b/Models/UserRecord.cs
@@ -13,6 +13,7 @@ public class UserRecord
     public string Persona { get; set; }
     public string Settings { get; set; }
     public string DefaultPath { get; set; }
+    public string SelectedApiKeyId { get; set; }
 
     public string GetEffectivePersona()
     {
diff --git a/Program.cs b/Program.cs
index 4b3fe23..cc3ee07 100644
--- a/Program.cs
+++ b/Program.cs
@@ -66,21 +66,14 @@ var embeddingBgService = new Gott.Services.EmbeddingBackgroundService(vectorSear
 builder.Services.AddSingleton(embeddingBgService);
 builder.Services.AddHostedService(sp => sp.GetRequiredService<Gott.Services.EmbeddingBackgroundService>());
 
-// AnthropicService (Singleton – shared zwischen ChatEndpoint und TelegramService)
-// Token wird aus DB geladen (api_keys Tabelle), Fallback auf Config
-var anthropicToken = "";
-var activeKey = dbService.GetActiveApiKey("anthropic").GetAwaiter().GetResult();
-if (activeKey != null)
-    anthropicToken = activeKey.ApiKey;
-else if (!string.IsNullOrWhiteSpace(builder.Configuration["AnthropicToken"]))
-    anthropicToken = builder.Configuration["AnthropicToken"];
+// AnthropicService (Singleton – Token wird pro Request vom User aufgelöst)
 var payloadLogging = builder.Configuration.GetValue<bool>("PayloadLogging", false);
 var payloadLoggingGzip = builder.Configuration.GetValue<bool>("PayloadLoggingGzip", false);
 builder.Services.AddSingleton<AnthropicService>(sp =>
 {
     var svc = new AnthropicService(
         sp.GetRequiredService<IHttpClientFactory>(),
-        anthropicToken, toolService, dbService, memoryService,
+        toolService, dbService, memoryService,
         payloadLogging, payloadLoggingGzip,
         vectorSearch: vectorSearchService,
         embeddingBg: embeddingBgService);
diff --git a/Services/AnthropicService.cs b/Services/AnthropicService.cs
index b6d5a83..96d3855 100644
--- a/Services/AnthropicService.cs
+++ b/Services/AnthropicService.cs
@@ -16,7 +16,6 @@ namespace Gott.Services;
 public class AnthropicService
 {
     private readonly IHttpClientFactory _httpFactory;
-    private string _token;
     private readonly ToolService _toolService;
     private readonly DatabaseService _db;
     private readonly MemoryService _memoryService;
@@ -27,10 +26,9 @@ public class AnthropicService
     private ChatService _chatService;
     private TelegramService _telegramService;
 
-    public AnthropicService(IHttpClientFactory httpFactory, string token, ToolService toolService, DatabaseService db, MemoryService memoryService = null, bool payloadLogging = false, bool payloadLoggingGzip = false, VectorSearchService vectorSearch = null, EmbeddingBackgroundService embeddingBg = null)
+    public AnthropicService(IHttpClientFactory httpFactory, ToolService toolService, DatabaseService db, MemoryService memoryService = null, bool payloadLogging = false, bool payloadLoggingGzip = false, VectorSearchService vectorSearch = null, EmbeddingBackgroundService embeddingBg = null)
     {
         _httpFactory = httpFactory;
-        _token = token;
         _toolService = toolService;
         _db = db;
         _memoryService = memoryService;
@@ -54,25 +52,17 @@ public class AnthropicService
         _telegramService = telegramService;
     }
 
-    /// <summary>
-    /// Aktualisiert den API-Token zur Laufzeit (z.B. wenn ein anderer Key aktiviert wird).
-    /// </summary>
-    public void UpdateToken(string token)
-    {
-        _token = token ?? "";
-    }
-
     /// <summary>
     /// Liest Usage-Header aus einer Anthropic-Response und aktualisiert die api_keys-Tabelle.
     /// Fire-and-forget – Fehler werden stillschweigend ignoriert.
     /// </summary>
-    private void TryUpdateKeyMeta(HttpResponseMessage httpResp)
+    private void TryUpdateKeyMeta(HttpResponseMessage httpResp, string apiToken)
     {
         try
         {
             var meta = AnthropicKeyChecker.ExtractMetaFromHeaders(httpResp.Headers);
-            if (meta == null || string.IsNullOrEmpty(_token)) return;
-            _ = _db.UpdateApiKeyMetaByToken(_token, meta.Status, meta.Plan, meta.Usage7d, meta.Usage5h);
+            if (meta == null || string.IsNullOrEmpty(apiToken)) return;
+            _ = _db.UpdateApiKeyMetaByToken(apiToken, meta.Status, meta.Plan, meta.Usage7d, meta.Usage5h);
         }
         catch { /* silent */ }
     }
@@ -84,6 +74,7 @@ public class AnthropicService
         List<object> messages,
         string chainId,
         string workspace,
+        string apiToken,
         string sessionId = null,
         string agentId = null,
         string userId = null,
@@ -181,7 +172,7 @@ public class AnthropicService
                 var hasRemote = remoteMgr?.GetBySessionId(sessionId) != null;
                 AddToolsToPayload(payload, workspace, agentId, useMemory, webSearchVersion, toolChoice, iterations, allowUserChoice, planMode, includeRemote: hasRemote, includeGitHubSearch: useGitHubSearch && _toolService.HasGitHubToken, includeSerperSearch: useSerperSearch && _toolService.HasSerperKey);
 
-                var client = CreateClient();
+                var client = CreateClient(apiToken);
                 var json = JsonSerializer.Serialize(payload, new JsonSerializerOptions { WriteIndented = true });
                 LogPayload(json, sessionId, chainId, iterations);
                 var httpContent = new StringContent(json, Encoding.UTF8, "application/json");
@@ -192,7 +183,7 @@ public class AnthropicService
                     workCt
                 );
 
-                TryUpdateKeyMeta(httpResp);
+                TryUpdateKeyMeta(httpResp, apiToken);
 
                 if (!httpResp.IsSuccessStatusCode)
                 {
@@ -227,7 +218,7 @@ public class AnthropicService
                     return;
                 }
 
-                var (stopReason, assistantContent, executedTools, streamErrorInfo) = await ProcessStream(response, httpResp, usage, workspace, agentId, workCt, sseCt, remoteMgr, sessionId, userId);
+                var (stopReason, assistantContent, executedTools, streamErrorInfo) = await ProcessStream(response, httpResp, usage, workspace, agentId, workCt, sseCt, remoteMgr, sessionId, userId, apiToken);
                 lastStopReason = stopReason;
                 promptTrimRetries = 0; // Erfolgreicher API-Call → Retry-Counter resetten
 
@@ -311,7 +302,7 @@ public class AnthropicService
                     // ── Review-Agent Phase ──
                     if (review != null && stopReason == "end_turn" && reviewRound < review.MaxReviewIterations)
                     {
-                        var reviewResult = await RunReview(response, review, messages, chainId, workspace, sessionId, usage, iterations, reviewRound, workCt, sseCt);
+                        var reviewResult = await RunReview(response, review, messages, chainId, workspace, sessionId, apiToken, usage, iterations, reviewRound, workCt, sseCt);
                         iterations += reviewResult.ReviewIterationCount;
                         reviewRound++;
 
@@ -336,7 +327,7 @@ public class AnthropicService
                     // ── Finalizer-Agent Phase ──
                     if (finalizer != null && stopReason == "end_turn")
                     {
-                        var finalizerIterations = await RunFinalizer(response, finalizer, messages, chainId, workspace, sessionId, usage, iterations, workCt, sseCt);
+                        var finalizerIterations = await RunFinalizer(response, finalizer, messages, chainId, workspace, sessionId, apiToken, usage, iterations, workCt, sseCt);
                         iterations += finalizerIterations;
                     }
 
@@ -467,6 +458,7 @@ public class AnthropicService
         string chainId,
         string workspace,
         string sessionId,
+        string apiToken,
         CancellationToken cancellationToken)
     {
         // Preparer läuft VOR dem Worker und nutzt den Request-CancellationToken direkt.
@@ -487,7 +479,7 @@ public class AnthropicService
         var (text, iterations) = await RunAgentChat(
             response, preparer.ModelId, preparer.SystemPrompt, preparer.AgentId,
             preparer.Workspace, preparer.UseMemory, preparer.WebSearchVersion,
-            preparer.ToolChoice, preparerMessages, chainId, sessionId, usage,
+            preparer.ToolChoice, preparerMessages, chainId, sessionId, apiToken, usage,
             0, "preparer", preparer.Agent?.Name ?? "Vorbereiter-Agent",
             cancellationToken, cancellationToken);
 
@@ -555,6 +547,7 @@ public class AnthropicService
         string chainId,
         string workspace,
         string sessionId,
+        string apiToken,
         TokenUsage usage,
         int baseIterations,
         int reviewRound,
@@ -579,7 +572,7 @@ public class AnthropicService
         var (reviewText, reviewIterations) = await RunAgentChat(
             response, review.ModelId, review.SystemPrompt, review.AgentId,
             workspace, review.UseMemory, review.WebSearchVersion,
-            review.ToolChoice, reviewMessages, chainId, sessionId, usage,
+            review.ToolChoice, reviewMessages, chainId, sessionId, apiToken, usage,
             baseIterations, "review", review.Agent?.Name ?? "Review-Agent",
             workCt, sseCt);
 
@@ -630,6 +623,7 @@ public class AnthropicService
         string chainId,
         string workspace,
         string sessionId,
+        string apiToken,
         TokenUsage usage,
         int baseIterations,
         CancellationToken workCt,
@@ -647,7 +641,7 @@ public class AnthropicService
         var (text, iterations) = await RunAgentChat(
             response, finalizer.ModelId, finalizer.SystemPrompt, finalizer.AgentId,
             finalizer.Workspace, finalizer.UseMemory, finalizer.WebSearchVersion,
-            finalizer.ToolChoice, finalizerMessages, chainId, sessionId, usage,
+            finalizer.ToolChoice, finalizerMessages, chainId, sessionId, apiToken, usage,
             baseIterations, "finalizer", finalizer.Agent?.Name ?? "Finalizer-Agent",
             workCt, sseCt);
 
@@ -794,6 +788,7 @@ public class AnthropicService
         List<object> messages,
         string chainId,
         string sessionId,
+        string apiToken,
         TokenUsage usage,
         int baseIterations,
         string agentType,
@@ -825,7 +820,7 @@ public class AnthropicService
 
             AddToolsToPayload(payload, agentWorkspace, agentId, useMemory, webSearchVersion, agentToolChoice, iterations);
 
-            var client = CreateClient();
+            var client = CreateClient(apiToken);
             var json = JsonSerializer.Serialize(payload, new JsonSerializerOptions { WriteIndented = true });
             LogPayload(json, sessionId, chainId, baseIterations + iterations);
             var httpContent = new StringContent(json, Encoding.UTF8, "application/json");
@@ -834,7 +829,7 @@ public class AnthropicService
                 new HttpRequestMessage(HttpMethod.Post, "https://api.anthropic.com/v1/messages") { Content = httpContent },
                 cancellationToken: workCt);
 
-            TryUpdateKeyMeta(httpResp);
+            TryUpdateKeyMeta(httpResp, apiToken);
 
             var respBody = await httpResp.Content.ReadAsStringAsync(workCt);
 
@@ -925,7 +920,7 @@ public class AnthropicService
 
                     string toolResult;
                     bool isError = false;
-                    try { toolResult = await _toolService.ExecuteTool(toolName, toolInput, agentWorkspace, _memoryService, agentId, workCt, vectorSearch: _vectorSearch, embeddingBg: _embeddingBg, db: _db, chatService: _chatService, anthropicService: this, telegramService: _telegramService); }
+                    try { toolResult = await _toolService.ExecuteTool(toolName, toolInput, agentWorkspace, _memoryService, agentId, workCt, vectorSearch: _vectorSearch, embeddingBg: _embeddingBg, db: _db, chatService: _chatService, anthropicService: this, telegramService: _telegramService, apiToken: apiToken); }
                     catch (OperationCanceledException) { throw; }
                     catch (Exception ex) { toolResult = $"Fehler: {ex.Message}"; isError = true; }
 
@@ -1047,7 +1042,7 @@ public class AnthropicService
 
                 AddToolsToPayload(payload, ctx.Workspace, ctx.AgentId, ctx.UseMemory, ctx.WebSearchVersion, ctx.ToolChoice, iterations);
 
-                var client = CreateClient();
+                var client = CreateClient(ctx.ApiToken);
                 var json = JsonSerializer.Serialize(payload, new JsonSerializerOptions { WriteIndented = true });
                 LogPayload(json, ctx.SessionId, ctx.ChainId, iterations);
                 var httpContent = new StringContent(json, Encoding.UTF8, "application/json");
@@ -1055,7 +1050,7 @@ public class AnthropicService
                 using var httpResp = await client.SendAsync(
                     new HttpRequestMessage(HttpMethod.Post, "https://api.anthropic.com/v1/messages") { Content = httpContent });
 
-                TryUpdateKeyMeta(httpResp);
+                TryUpdateKeyMeta(httpResp, ctx.ApiToken);
 
                 var respBody = await httpResp.Content.ReadAsStringAsync();
 
@@ -1133,7 +1128,7 @@ public class AnthropicService
 
                         string toolResult;
                         bool isError = false;
-                        try { toolResult = await _toolService.ExecuteTool(toolName, toolInput, ctx.Workspace, _memoryService, ctx.AgentId, vectorSearch: _vectorSearch, embeddingBg: _embeddingBg, db: _db, chatService: _chatService, anthropicService: this, userId: ctx.Session?.UserId, telegramService: _telegramService); }
+                        try { toolResult = await _toolService.ExecuteTool(toolName, toolInput, ctx.Workspace, _memoryService, ctx.AgentId, vectorSearch: _vectorSearch, embeddingBg: _embeddingBg, db: _db, chatService: _chatService, anthropicService: this, userId: ctx.Session?.UserId, telegramService: _telegramService, apiToken: ctx.ApiToken); }
                         catch (OperationCanceledException) { throw; }
                         catch (Exception ex) { toolResult = $"Fehler: {ex.Message}"; isError = true; }
 
@@ -1243,7 +1238,8 @@ public class AnthropicService
         CancellationToken sseCt = default,
         RemoteConnectionManager remoteMgr = null,
         string sessionId = null,
-        string userId = null)
+        string userId = null,
+        string apiToken = null)
     {
         var stream = await httpResp.Content.ReadAsStreamAsync(workCt);
         // Bei Cancellation den Stream disposen, damit ReadLineAsync sofort abbricht.
@@ -1425,7 +1421,7 @@ public class AnthropicService
 
                             string toolResult;
                             bool isError = false;
-                            try { toolResult = await _toolService.ExecuteTool(currentToolName, inputEl, workspace, _memoryService, agentId, workCt, remoteMgr: remoteMgr, sessionId: sessionId, vectorSearch: _vectorSearch, embeddingBg: _embeddingBg, db: _db, chatService: _chatService, anthropicService: this, userId: userId, telegramService: _telegramService); }
+                            try { toolResult = await _toolService.ExecuteTool(currentToolName, inputEl, workspace, _memoryService, agentId, workCt, remoteMgr: remoteMgr, sessionId: sessionId, vectorSearch: _vectorSearch, embeddingBg: _embeddingBg, db: _db, chatService: _chatService, anthropicService: this, userId: userId, telegramService: _telegramService, apiToken: apiToken); }
                             catch (OperationCanceledException) { throw; }
                             catch (Exception ex) { toolResult = $"Fehler: {ex.Message}"; isError = true; }
 
@@ -1694,10 +1690,10 @@ public class AnthropicService
         return 0;
     }
 
-    private HttpClient CreateClient()
+    private HttpClient CreateClient(string apiToken)
     {
         var client = _httpFactory.CreateClient();
-        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", _token);
+        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiToken);
         client.DefaultRequestHeaders.Add("anthropic-version", "2023-06-01");
         client.DefaultRequestHeaders.Add("anthropic-beta", "claude-code-20250219,oauth-2025-04-20,code-execution-2025-08-25");
         client.DefaultRequestHeaders.Add("User-Agent", "claude-cli/2.1.2 (external, cli)");
diff --git a/Services/CronjobService.cs b/Services/CronjobService.cs
index 27e6141..cb2008f 100644
--- a/Services/CronjobService.cs
+++ b/Services/CronjobService.cs
@@ -86,6 +86,12 @@ public class CronjobService : BackgroundService
         if (ctx == null)
             throw new Exception("Session oder Agent nicht gefunden / nicht konfiguriert");
 
+        // API-Key des Cronjob-Owners auflösen
+        var userApiKey = await _db.GetUserSelectedApiKey(job.UserId);
+        if (userApiKey == null)
+            throw new Exception($"Kein API-Key für User {job.UserId} ausgewählt");
+        ctx.ApiToken = userApiKey.ApiKey;
+
         // History aus DB laden
         var history = await _chatService.BuildHistoryFromDb(job.SessionId, promptBlocks: ctx.PromptBlocks);
 
@@ -134,6 +140,15 @@ public class CronjobService : BackgroundService
                 return;
             }
 
+            // API-Key des Cronjob-Owners auflösen
+            var notifyApiKey = await _db.GetUserSelectedApiKey(job.UserId);
+            if (notifyApiKey == null)
+            {
+                _logger.LogWarning("Kein API-Key für User {UserId} (Cronjob '{Name}' Notification)", job.UserId, job.Name);
+                return;
+            }
+            notifyCtx.ApiToken = notifyApiKey.ApiKey;
+
             // Kurze Zusammenfassung als User-Nachricht in die Notify-Session schreiben
             var summary = $"[Cronjob \"{job.Name}\" wurde in Session \"{job.SessionName}\" ausgeführt]\n\nAntwort:\n{Truncate(responseText, 2000)}";
 
diff --git a/Services/DatabaseService.Integrations.cs b/Services/DatabaseService.Integrations.cs
index a12860f..83a82dd 100644
--- a/Services/DatabaseService.Integrations.cs
+++ b/Services/DatabaseService.Integrations.cs
@@ -324,7 +324,7 @@ public partial class DatabaseService
                         {
                             var now = DateTime.UtcNow.ToString("o");
                             conn.Execute(@"
-                                INSERT INTO api_keys (key_id, provider, name, api_key, is_active, created_at, updated_at)
+                                INSERT INTO api_keys (key_id, provider, name, api_key, is_public, created_at, updated_at)
                                 VALUES (@keyId, 'anthropic', 'Migriert aus Config', @token, 1, @now, @now)",
                                 new { keyId = Guid.NewGuid().ToString("N"), token, now });
                             Console.WriteLine("[Migration] AnthropicToken aus appsettings.Production.json → api_keys migriert");
@@ -351,12 +351,11 @@ public partial class DatabaseService
             new { provider });
     }
 
-    public async Task<ApiKeyRecord> GetActiveApiKey(string provider)
+    public async Task<IEnumerable<ApiKeyRecord>> GetPublicApiKeys()
     {
         using var conn = CreateConnection();
-        return await conn.QuerySingleOrDefaultAsync<ApiKeyRecord>(
-            "SELECT * FROM api_keys WHERE provider = @provider AND is_active = 1 LIMIT 1",
-            new { provider });
+        return await conn.QueryAsync<ApiKeyRecord>(
+            "SELECT * FROM api_keys WHERE is_public = 1 ORDER BY provider, name");
     }
 
     public async Task<ApiKeyRecord> GetApiKey(string keyId)
@@ -372,8 +371,8 @@ public partial class DatabaseService
     {
         using var conn = CreateConnection();
         await conn.ExecuteAsync(@"
-            INSERT INTO api_keys (key_id, provider, name, api_key, is_active, status, plan, usage_7d, usage_5h, checked_at, source_url, created_at, updated_at)
-            VALUES (@KeyId, @Provider, @Name, @ApiKey, @IsActive, @Status, @Plan, @Usage7d, @Usage5h, @CheckedAt, @SourceUrl, @CreatedAt, @UpdatedAt)",
+            INSERT INTO api_keys (key_id, provider, name, api_key, is_public, status, plan, usage_7d, usage_5h, checked_at, source_url, created_at, updated_at)
+            VALUES (@KeyId, @Provider, @Name, @ApiKey, @IsPublic, @Status, @Plan, @Usage7d, @Usage5h, @CheckedAt, @SourceUrl, @CreatedAt, @UpdatedAt)",
             record);
         return await conn.ExecuteScalarAsync<long>("SELECT last_insert_rowid()");
     }
@@ -409,29 +408,16 @@ public partial class DatabaseService
         using var conn = CreateConnection();
         await conn.ExecuteAsync(@"
             UPDATE api_keys SET status = @status, plan = @plan, usage_7d = @usage7d, usage_5h = @usage5h, checked_at = @now, updated_at = @now
-            WHERE api_key = @apiKey AND is_active = 1",
+            WHERE api_key = @apiKey",
             new { apiKey, status, plan, usage7d, usage5h, now = DateTime.UtcNow.ToString("o") });
     }
 
-    public async Task SetActiveApiKey(string keyId, string provider)
-    {
-        using var conn = CreateConnection();
-        // Erst alle deaktivieren
-        await conn.ExecuteAsync(
-            "UPDATE api_keys SET is_active = 0, updated_at = @now WHERE provider = @provider",
-            new { provider, now = DateTime.UtcNow.ToString("o") });
-        // Dann den gewählten aktivieren
-        await conn.ExecuteAsync(
-            "UPDATE api_keys SET is_active = 1, updated_at = @now WHERE key_id = @keyId",
-            new { keyId, now = DateTime.UtcNow.ToString("o") });
-    }
-
-    public async Task DeactivateApiKey(string keyId)
+    public async Task SetApiKeyPublic(string keyId, bool isPublic)
     {
         using var conn = CreateConnection();
         await conn.ExecuteAsync(
-            "UPDATE api_keys SET is_active = 0, updated_at = @now WHERE key_id = @keyId",
-            new { keyId, now = DateTime.UtcNow.ToString("o") });
+            "UPDATE api_keys SET is_public = @isPublic, updated_at = @now WHERE key_id = @keyId",
+            new { keyId, isPublic, now = DateTime.UtcNow.ToString("o") });
     }
 
     public async Task DeleteApiKey(string keyId)
diff --git a/Services/DatabaseService.Users.cs b/Services/DatabaseService.Users.cs
index d0fbfa3..9976e61 100644
--- a/Services/DatabaseService.Users.cs
+++ b/Services/DatabaseService.Users.cs
@@ -187,4 +187,32 @@ public partial class DatabaseService
         await conn.ExecuteAsync("DELETE FROM users WHERE user_id = @userId", new { userId });
     }
 
+    // ── User API-Key Auswahl ──
+
+    public async Task SetUserSelectedApiKey(string userId, string keyId)
+    {
+        using var conn = CreateConnection();
+        await conn.ExecuteAsync(
+            "UPDATE users SET selected_api_key_id = @keyId, updated_at = @now WHERE user_id = @userId",
+            new { userId, keyId = (object)keyId ?? DBNull.Value, now = DateTime.UtcNow.ToString("o") });
+    }
+
+    public async Task<string> GetUserSelectedApiKeyId(string userId)
+    {
+        using var conn = CreateConnection();
+        return await conn.QuerySingleOrDefaultAsync<string>(
+            "SELECT selected_api_key_id FROM users WHERE user_id = @userId",
+            new { userId });
+    }
+
+    public async Task<ApiKeyRecord> GetUserSelectedApiKey(string userId)
+    {
+        using var conn = CreateConnection();
+        return await conn.QuerySingleOrDefaultAsync<ApiKeyRecord>(@"
+            SELECT k.* FROM api_keys k
+            INNER JOIN users u ON u.selected_api_key_id = k.key_id
+            WHERE u.user_id = @userId",
+            new { userId });
+    }
+
 }
diff --git a/Services/DatabaseService.cs b/Services/DatabaseService.cs
index b5faf0e..c1b8883 100644
--- a/Services/DatabaseService.cs
+++ b/Services/DatabaseService.cs
@@ -341,6 +341,10 @@ public partial class DatabaseService
         TryAddColumn(conn, "api_keys", "usage_5h", "REAL");
         TryAddColumn(conn, "api_keys", "checked_at", "TEXT");
         TryAddColumn(conn, "api_keys", "source_url", "TEXT");
+        TryAddColumn(conn, "api_keys", "is_public", "INTEGER NOT NULL DEFAULT 0");
+
+        // users: ausgewählter API-Key
+        TryAddColumn(conn, "users", "selected_api_key_id", "TEXT");
 
         // Migration: Bestehende PNG/JPEG-Avatare/Images zu WebP konvertieren
         MigrateImagesToWebP(conn);
diff --git a/Services/TelegramService.cs b/Services/TelegramService.cs
index 31f5118..8626041 100644
--- a/Services/TelegramService.cs
+++ b/Services/TelegramService.cs
@@ -80,7 +80,7 @@ public class TelegramService
             return;
         }
 
-        await HandleMessage(chatId, text, bot.BotToken, session);
+        await HandleMessage(chatId, text, bot.BotToken, bot.UserId, session);
     }
 
     private async Task HandleStart(long chatId, TelegramBotRecord bot, SessionRecord session)
@@ -159,15 +159,24 @@ public class TelegramService
 
     // ── Nachricht an Claude weiterleiten ──
 
-    private async Task HandleMessage(long chatId, string userText, string botToken, SessionRecord session)
+    private async Task HandleMessage(long chatId, string userText, string botToken, string botUserId, SessionRecord session)
     {
-        var ctx = await _chatService.PrepareContext(session.SessionId, null, _maxIterations);
+        var ctx = await _chatService.PrepareContext(session.SessionId, botUserId, _maxIterations);
         if (ctx == null)
         {
             await SendMessage(chatId, botToken, "❌ Kein Agent konfiguriert. Bitte weise der Session im Web-UI einen Agent zu.");
             return;
         }
 
+        // API-Key des Bot-Owners auflösen
+        var userApiKey = await _db.GetUserSelectedApiKey(botUserId);
+        if (userApiKey == null)
+        {
+            await SendMessage(chatId, botToken, "❌ Kein API-Key ausgewählt. Der Bot-Besitzer muss im Web-UI einen Key auswählen.");
+            return;
+        }
+        ctx.ApiToken = userApiKey.ApiKey;
+
         await SendChatAction(chatId, botToken, "typing");
 
         try
diff --git a/Services/ToolService.cs b/Services/ToolService.cs
index ba51ff0..de38ee2 100644
--- a/Services/ToolService.cs
+++ b/Services/ToolService.cs
@@ -391,7 +391,7 @@ public class ToolService
         };
     }
 
-    public async Task<string> ExecuteTool(string name, JsonElement input, string workspace, MemoryService memoryService = null, string agentId = null, CancellationToken cancellationToken = default, RemoteConnectionManager remoteMgr = null, string sessionId = null, VectorSearchService vectorSearch = null, EmbeddingBackgroundService embeddingBg = null, DatabaseService db = null, ChatService chatService = null, AnthropicService anthropicService = null, string userId = null, TelegramService telegramService = null)
+    public async Task<string> ExecuteTool(string name, JsonElement input, string workspace, MemoryService memoryService = null, string agentId = null, CancellationToken cancellationToken = default, RemoteConnectionManager remoteMgr = null, string sessionId = null, VectorSearchService vectorSearch = null, EmbeddingBackgroundService embeddingBg = null, DatabaseService db = null, ChatService chatService = null, AnthropicService anthropicService = null, string userId = null, TelegramService telegramService = null, string apiToken = null)
     {
         switch (name)
         {
@@ -765,9 +765,10 @@ public class ToolService
                     return "Fehler: Kann keine Nachricht an die eigene Session senden";
 
                 // Context für Ziel-Session vorbereiten (analog zu CronjobService)
-                var ctx = await chatService.PrepareContext(targetSessionId, userId: null);
+                var ctx = await chatService.PrepareContext(targetSessionId, userId: userId);
                 if (ctx == null)
                     return $"Fehler: Session '{targetSession.Name}' ist nicht konfiguriert (kein Agent zugewiesen?)";
+                ctx.ApiToken = apiToken;
 
                 // History aufbauen – User-Message NICHT in DB speichern (wie Cronjob)
                 // Stattdessen als kontextualisierte Nachricht in die History injizieren
diff --git a/wwwroot/css/chat.css b/wwwroot/css/chat.css
index f4e31ab..1a95e65 100644
--- a/wwwroot/css/chat.css
+++ b/wwwroot/css/chat.css
@@ -45,6 +45,14 @@
   border-color: var(--f3-border);
 }
 
+.chat-usage-overlay .usage-badge-nodata {
+  flex-direction: row;
+  align-items: center;
+  width: auto;
+  gap: var(--badge-spacing);
+  padding: var(--box-padding);
+}
+
 #chat {
   flex: 1;
   overflow-y: auto;
diff --git a/wwwroot/index.html b/wwwroot/index.html
index 43de231..498d926 100644
--- a/wwwroot/index.html
+++ b/wwwroot/index.html
@@ -559,6 +559,7 @@
       <div class="form">
         <div class="section-header">
           <h2>API-Key</h2>
+          <button id="apiKeysCheckAllBtn" class="section-add-btn" style="margin-right: var(--badge-spacing); margin-left: auto;"><i class="fa fa-refresh"></i> Alle prüfen</button>
           <button id="apiKeysNewBtn" class="section-add-btn"><i class="fa fa-plus"></i> Neuer Key</button>
         </div>
         <div id="apiKeysList" class="admin-user-list"></div>
diff --git a/wwwroot/js/api.js b/wwwroot/js/api.js
index 900569d..c12e9a7 100644
--- a/wwwroot/js/api.js
+++ b/wwwroot/js/api.js
@@ -219,10 +219,16 @@ function apiSaveServerSettings(data) { return _put('/api/admin/server-settings',
 function apiGetApiKeys() { return _get('/api/admin/api-keys'); }
 function apiCreateApiKey(data) { return _post('/api/admin/api-keys', data, 'Fehler beim Erstellen'); }
 function apiUpdateApiKey(id, data) { return _put('/api/admin/api-keys/' + id, data, 'Fehler beim Aktualisieren'); }
-function apiActivateApiKey(id) { return _put('/api/admin/api-keys/' + id + '/activate', undefined, 'Fehler beim Aktivieren'); }
-function apiDeactivateApiKey(id) { return _put('/api/admin/api-keys/' + id + '/deactivate', undefined, 'Fehler beim Deaktivieren'); }
+function apiToggleApiKeyPublic(id) { return _put('/api/admin/api-keys/' + id + '/public', undefined, 'Fehler beim Umschalten'); }
+
+// ── User Key Selection API ──
+
+function apiGetAvailableKeys() { return _get('/api/api-keys/available', []); }
+function apiSelectApiKey(keyId) { return _put('/api/api-keys/select/' + keyId, undefined, 'Fehler beim Auswählen'); }
+function apiGetSelectedKey() { return _get('/api/api-keys/selected', null); }
 function apiDeleteApiKey(id) { return _del('/api/admin/api-keys/' + id, 'Fehler beim Löschen'); }
 function apiCheckApiKey(id) { return _post('/api/admin/api-keys/' + id + '/check', undefined, 'Fehler beim Prüfen'); }
+function apiCheckAllApiKeys() { return _post('/api/admin/api-keys/check-all', undefined, 'Fehler beim Prüfen'); }
 
 // ── Key Scanner API (Admin) ──
 
diff --git a/wwwroot/js/pages/api-keys-page.js b/wwwroot/js/pages/api-keys-page.js
index 597b6c4..f378087 100644
--- a/wwwroot/js/pages/api-keys-page.js
+++ b/wwwroot/js/pages/api-keys-page.js
@@ -63,6 +63,7 @@ registerPage('api-keys', {
 
     var list = document.getElementById('apiKeysList');
     var newBtn = document.getElementById('apiKeysNewBtn');
+    var checkAllBtn = document.getElementById('apiKeysCheckAllBtn');
     var form = document.getElementById('apiKeysForm');
     var formTitle = document.getElementById('apiKeysFormTitle');
     var providerSelect = document.getElementById('apiKeysProvider');
@@ -119,21 +120,14 @@ registerPage('api-keys', {
         var badgeRow = document.createElement('div');
         badgeRow.style.cssText = 'display:flex;align-items:center;gap:8px;margin-top:2px';
 
-        if (key.isActive) {
-          var deactivateBtn = document.createElement('button');
-          deactivateBtn.className = 'icon-btn';
-          deactivateBtn.title = 'Deaktivieren';
-          deactivateBtn.innerHTML = '<i class="fa fa-toggle-on" style="color:var(--accent)"></i>';
-          deactivateBtn.addEventListener('click', function() { deactivateKey(key); });
-          badgeRow.appendChild(deactivateBtn);
-        } else {
-          var activateBtn = document.createElement('button');
-          activateBtn.className = 'icon-btn';
-          activateBtn.title = 'Aktivieren';
-          activateBtn.innerHTML = '<i class="fa fa-toggle-off"></i>';
-          activateBtn.addEventListener('click', function() { activateKey(key); });
-          badgeRow.appendChild(activateBtn);
-        }
+        var publicBtn = document.createElement('button');
+        publicBtn.className = 'icon-btn';
+        publicBtn.title = key.isPublic ? 'Öffentlich (klicken zum Privatschalten)' : 'Privat (klicken zum Veröffentlichen)';
+        publicBtn.innerHTML = key.isPublic
+          ? '<i class="fa fa-globe" style="color:var(--accent)"></i>'
+          : '<i class="fa fa-lock"></i>';
+        publicBtn.addEventListener('click', function() { togglePublic(key); });
+        badgeRow.appendChild(publicBtn);
 
         var usageBadge = createUsageBadge(key.usage5h, key.usage7d);
         if (usageBadge) badgeRow.appendChild(usageBadge);
@@ -234,20 +228,10 @@ registerPage('api-keys', {
       nameInput.focus();
     }
 
-    async function activateKey(key) {
+    async function togglePublic(key) {
       try {
-        await apiActivateApiKey(key.keyId);
-        showToast(key.name + ' aktiviert');
-        await loadKeys();
-      } catch (err) {
-        showToast(err.message, 'error');
-      }
-    }
-
-    async function deactivateKey(key) {
-      try {
-        await apiDeactivateApiKey(key.keyId);
-        showToast(key.name + ' deaktiviert');
+        await apiToggleApiKeyPublic(key.keyId);
+        showToast(key.name + (key.isPublic ? ' privat geschaltet' : ' veröffentlicht'));
         await loadKeys();
       } catch (err) {
         showToast(err.message, 'error');
@@ -265,6 +249,19 @@ registerPage('api-keys', {
       }
     }
 
+    // Alle Keys prüfen
+    checkAllBtn.addEventListener('click', function() {
+      withButtonLoading(checkAllBtn, 'Alle prüfen', async function() {
+        try {
+          var result = await apiCheckAllApiKeys();
+          showToast(result.checked_ + ' Keys geprüft');
+          await loadKeys();
+        } catch (err) {
+          showToast(err.message, 'error');
+        }
+      });
+    });
+
     // Neuer Key
     newBtn.addEventListener('click', function() {
       editingKeyId = null;
diff --git a/wwwroot/js/pages/chat-page.js b/wwwroot/js/pages/chat-page.js
index 95dacc7..98f7ee5 100644
--- a/wwwroot/js/pages/chat-page.js
+++ b/wwwroot/js/pages/chat-page.js
@@ -44,17 +44,25 @@ function _createChatUsageBadge(usage5h, usage7d) {
 }
 
 async function _initChatUsageBadge() {
-  if (!currentUser || !currentUser.isAdmin) return;
+  if (!currentUser) return;
   var container = document.getElementById('chatUsageBadge');
   if (!container) return;
 
   try {
-    var keys = await apiGetApiKeys();
-    var activeKey = keys.find(function(k) { return k.isActive; });
-    if (!activeKey) { container.hidden = true; return; }
+    var selectedKey = await apiGetSelectedKey();
+    if (!selectedKey || !selectedKey.selected) {
+      container.innerHTML = '';
+      var noKeyBtn = document.createElement('button');
+      noKeyBtn.className = 'chat-usage-nokey';
+      noKeyBtn.innerHTML = '<i class="fa fa-key"></i> Key auswählen';
+      noKeyBtn.addEventListener('click', function() { _showKeySwitchModal(); });
+      container.appendChild(noKeyBtn);
+      container.hidden = false;
+      return;
+    }
 
-    _chatUsageKeyId = activeKey.keyId;
-    _renderChatUsageBadge(container, activeKey);
+    _chatUsageKeyId = selectedKey.keyId;
+    _renderChatUsageBadge(container, selectedKey);
     container.hidden = false;
 
     // Scroll-Listener: Badge ausblenden wenn User nach oben scrollt
@@ -73,13 +81,12 @@ async function _initChatUsageBadge() {
 }
 
 async function _refreshChatUsageBadge() {
-  if (!currentUser || !currentUser.isAdmin) return;
+  if (!currentUser) return;
   var container = document.getElementById('chatUsageBadge');
   if (!container || !_chatUsageKeyId) return;
   try {
-    var keys = await apiGetApiKeys();
-    var activeKey = keys.find(function(k) { return k.isActive; });
-    if (activeKey) _renderChatUsageBadge(container, activeKey);
+    var selectedKey = await apiGetSelectedKey();
+    if (selectedKey) _renderChatUsageBadge(container, selectedKey);
   } catch(e) { /* ignore */ }
 }
 
@@ -87,52 +94,68 @@ function _renderChatUsageBadge(container, key) {
   container.innerHTML = '';
 
   var badge = _createChatUsageBadge(key.usage5h, key.usage7d);
-  if (badge) {
-    badge.addEventListener('click', function(e) {
-      e.stopPropagation();
-      _showKeySwitchModal();
-    });
-    badge.title = (key.name || 'API Key') + ' · ' + (key.plan || '?');
-    container.appendChild(badge);
+  if (!badge) {
+    badge = document.createElement('div');
+    badge.className = 'usage-badge usage-badge-nodata';
+    badge.innerHTML = '<i class="fa fa-key"></i> ' + (key.name || 'API Key');
   }
-
-  var checkBtn = document.createElement('button');
-  checkBtn.className = 'chat-usage-check icon-btn';
-  checkBtn.innerHTML = '<i class="fa fa-refresh"></i>';
-  checkBtn.title = 'Key prüfen';
-  checkBtn.addEventListener('click', async function(e) {
+  badge.addEventListener('click', function(e) {
     e.stopPropagation();
-    checkBtn.disabled = true;
-    checkBtn.querySelector('i').className = 'fa fa-spinner fa-spin';
-    try {
-      var result = await apiCheckApiKey(_chatUsageKeyId);
-      if (result) {
-        var keys = await apiGetApiKeys();
-        var activeKey = keys.find(function(k) { return k.isActive; });
-        if (activeKey) _renderChatUsageBadge(container, activeKey);
-      }
-    } catch(e) {
-      console.error('Key check failed:', e);
-    }
-    checkBtn.disabled = false;
-    checkBtn.querySelector('i').className = 'fa fa-refresh';
+    _showKeySwitchModal();
   });
-  container.appendChild(checkBtn);
+  badge.title = (key.name || 'API Key') + ' · ' + (key.plan || '?');
+  badge.style.cursor = 'pointer';
+  container.appendChild(badge);
+
+  // Check-Button nur für Admins
+  if (currentUser && currentUser.isAdmin) {
+    var checkBtn = document.createElement('button');
+    checkBtn.className = 'chat-usage-check icon-btn';
+    checkBtn.innerHTML = '<i class="fa fa-refresh"></i>';
+    checkBtn.title = 'Key prüfen';
+    checkBtn.addEventListener('click', async function(e) {
+      e.stopPropagation();
+      checkBtn.disabled = true;
+      checkBtn.querySelector('i').className = 'fa fa-spinner fa-spin';
+      try {
+        await apiCheckApiKey(_chatUsageKeyId);
+        var selectedKey = await apiGetSelectedKey();
+        if (selectedKey) _renderChatUsageBadge(container, selectedKey);
+      } catch(e) {
+        console.error('Key check failed:', e);
+      }
+      checkBtn.disabled = false;
+      checkBtn.querySelector('i').className = 'fa fa-refresh';
+    });
+    container.appendChild(checkBtn);
+  }
 }
 
 async function _showKeySwitchModal() {
   var keys = [];
-  try { keys = await apiGetApiKeys(); } catch(e) { return; }
+  try { keys = await apiGetAvailableKeys(); } catch(e) { return; }
+
+  var selectedKey = null;
+  try { selectedKey = await apiGetSelectedKey(); } catch(e) { /* ignore */ }
+  var selectedKeyId = selectedKey ? selectedKey.keyId : null;
 
   var { body, close } = _createModal('API Key wechseln', { modal: 'key-switch-modal' });
 
+  if (keys.length === 0) {
+    var empty = document.createElement('div');
+    empty.style.cssText = 'padding:1rem;text-align:center;opacity:0.7';
+    empty.textContent = 'Keine Keys verfügbar. Ein Admin muss Keys als öffentlich markieren.';
+    body.appendChild(empty);
+    return;
+  }
+
   var list = document.createElement('div');
   list.className = 'key-switch-list';
 
   keys.forEach(function(key) {
     var row = document.createElement('div');
     row.className = 'key-switch-row';
-    if (key.isActive) row.classList.add('active');
+    if (key.keyId === selectedKeyId) row.classList.add('active');
 
     var info = document.createElement('div');
     info.className = 'key-switch-info';
@@ -157,15 +180,13 @@ async function _showKeySwitchModal() {
       row.appendChild(badge);
     }
 
-    if (!key.isActive) {
+    if (key.keyId !== selectedKeyId) {
       row.style.cursor = 'pointer';
       row.addEventListener('click', async function() {
         row.style.opacity = '0.5';
         row.style.pointerEvents = 'none';
         try {
-          var activeKey = keys.find(function(k) { return k.isActive; });
-          if (activeKey) await apiDeactivateApiKey(activeKey.keyId);
-          await apiActivateApiKey(key.keyId);
+          await apiSelectApiKey(key.keyId);
           close();
           await _initChatUsageBadge();
         } catch(e) {