diff --git a/Endpoints/SessionEndpoint.cs b/Endpoints/SessionEndpoint.cs
index f6de954..d2d75de 100644
--- a/Endpoints/SessionEndpoint.cs
+++ b/Endpoints/SessionEndpoint.cs
@@ -26,6 +26,7 @@ public static class SessionEndpoint
         app.MapDelete("/api/sessions/{sessionId}", HandleDelete);
         app.MapGet("/api/sessions/{sessionId}/system-prompt", HandleSystemPrompt);
         app.MapGet("/api/sessions/{sessionId}/system-prompt-blocks", HandleSystemPromptBlocks);
+        app.MapGet("/api/sessions/{sessionId}/payload-preview", HandlePayloadPreview);
         app.MapGet("/api/sessions/{sessionId}/streaming", HandleStreaming);
         app.MapPost("/api/sessions/{sessionId}/exec", HandleExec);
         app.MapGet("/api/sessions/{sessionId}/git-status", HandleGitStatus);
@@ -266,6 +267,75 @@ public static class SessionEndpoint
         await ctx.Response.WriteAsJsonAsync(blocks.Select(b => new { b.Icon, b.Label, b.Content }));
     }
 
+    private static async Task HandlePayloadPreview(HttpContext ctx, DatabaseService db, MemoryService memoryService, SkillService skillService, ChatService chatService, ToolService toolService, ServerSettingsService settings)
+    {
+        var result = await ResolvePromptContext(ctx, db, memoryService);
+        if (result == null) return;
+        var (session, agent, marked, memDir, skills, user, workspace, planMode) = result.Value;
+
+        // System-Prompt
+        var promptBlocks = SystemPromptBuilder.BuildBlocks(agent, session, marked, memoryService, memDir,
+            skills, skillService, userPersona: user?.GetEffectivePersona(), resolvedWorkspace: workspace, planMode: planMode);
+        var systemPromptText = string.Join("\n\n", promptBlocks.Select(b => b.Content));
+
+        var systemPrompt = new List<object>();
+        if (!string.IsNullOrWhiteSpace(systemPromptText))
+            systemPrompt.Add(new { type = "text", text = systemPromptText });
+
+        // Model
+        var modelId = ChatService.ResolveModelId(agent.Model);
+
+        // Messages aus der DB (exakt wie beim Chat)
+        var messages = await chatService.BuildHistoryFromDb(session.SessionId, promptBlocks: promptBlocks);
+
+        // Tools (exakt wie AddToolsToPayload es machen würde)
+        var hasWorkspace = !string.IsNullOrEmpty(workspace);
+        var includeMemory = agent.UseMemory && !string.IsNullOrEmpty(agent.AgentId);
+        var includeGitHubSearch = agent.UseGitHubSearch && toolService.HasGitHubToken;
+        var includeSerperSearch = agent.UseSerperSearch && toolService.HasSerperKey;
+        var hasTools = hasWorkspace || includeMemory || includeGitHubSearch || includeSerperSearch;
+
+        var tools = new List<object>();
+        if (hasTools)
+        {
+            var allTools = toolService.GetToolDefinitions(
+                includeFileTools: hasWorkspace,
+                includeMemory: includeMemory,
+                includeUserChoice: agent.AllowUserChoice,
+                includeGitHubSearch: includeGitHubSearch,
+                includeSerperSearch: includeSerperSearch);
+            if (planMode)
+                allTools = toolService.FilterReadOnlyTools(allTools);
+            tools.AddRange(allTools);
+        }
+        if (!string.IsNullOrEmpty(agent.WebSearchVersion))
+            tools.Add(new { type = agent.WebSearchVersion, name = "web_search", max_uses = 5 });
+
+        var toolChoice = hasTools || !string.IsNullOrEmpty(agent.WebSearchVersion) ? "any" : null;
+        var effectiveChoice = toolChoice == "any" ? "any" : "auto";
+
+        // Payload zusammenbauen (Anthropic-Format)
+        var payload = new Dictionary<string, object>
+        {
+            ["model"] = modelId,
+            ["max_tokens"] = 16384,
+            ["messages"] = messages,
+            ["stream"] = true
+        };
+
+        if (systemPrompt.Count > 0)
+            payload["system"] = systemPrompt;
+
+        if (tools.Count > 0)
+        {
+            payload["tools"] = tools;
+            payload["tool_choice"] = new { type = effectiveChoice };
+        }
+
+        ctx.Response.ContentType = "application/json; charset=utf-8";
+        await ctx.Response.WriteAsync(JsonSerializer.Serialize(payload, new JsonSerializerOptions { WriteIndented = true }));
+    }
+
     private static async Task HandleStreaming(HttpContext ctx, DatabaseService db, StreamingTracker streamingTracker)
     {
         var userId = ctx.GetUserId();
diff --git a/Services/ChatService.cs b/Services/ChatService.cs
index a7e3b1e..2c0ec84 100644
--- a/Services/ChatService.cs
+++ b/Services/ChatService.cs
@@ -549,9 +549,10 @@ Für welche Plattform soll die App entwickelt werden? Web, Mobile oder Desktop?
                 history.RemoveRange(0, removeCount);
         }
 
-        // Reminder einfügen: alle ~30 user/assistant-Paare ein Reminder-Paar einfügen
+        // Reminder einfügen: von hinten gezählt – halbes Intervall vor Ende, dann volle Intervalle
         var reminder = SystemPromptBuilder.BuildReminder(promptBlocks);
-        if (!string.IsNullOrWhiteSpace(reminder) && ReminderInterval > 0 && history.Count > ReminderInterval)
+        int halfInterval = ReminderInterval / 2;
+        if (!string.IsNullOrWhiteSpace(reminder) && ReminderInterval > 0 && history.Count > halfInterval)
         {
             var reminderUser = new Dictionary<string, object>
             {
@@ -564,17 +565,29 @@ Für welche Plattform soll die App entwickelt werden? Web, Mobile oder Desktop?
                 ["content"] = new List<object> { new { type = "text", text = "Verstanden." } }
             };
 
-            // Alle 30 Messages ein Reminder-Paar einfügen (von hinten nach vorne, damit Indizes stimmen)
-            var insertPositions = new List<int>();
-            int messageCount = 0;
-            for (int i = 0; i < history.Count; i++)
+            // Zielpositionen von hinten berechnen:
+            // Erste Position: history.Count - halfInterval (z.B. 15 vom Ende)
+            // Weitere Positionen: jeweils - ReminderInterval (z.B. 30er-Schritte rückwärts)
+            var targetPositions = new List<int>();
+            int pos = history.Count - halfInterval;
+            while (pos > 0)
             {
-                messageCount++;
-                if (messageCount > 0 && messageCount % ReminderInterval == 0)
+                targetPositions.Add(pos);
+                pos -= ReminderInterval;
+            }
+
+            // Für jede Zielposition die nächste valide Einfügestelle finden
+            var insertPositions = new List<int>();
+            foreach (int target in targetPositions)
+            {
+                // Suche ab target rückwärts nach einer assistant-Message,
+                // deren Folge-Message kein tool_result ist
+                for (int i = Math.Min(target, history.Count - 1); i >= 1; i--)
                 {
-                    // Position nach dem aktuellen Element – aber nur einfügen wenn es eine
-                    // assistant-Message ist (damit user/assistant-Alternierung nicht bricht)
-                    // UND die nächste Message kein tool_result ist (sonst bricht tool_use/tool_result-Paar)
+                    if (!(history[i] is Dictionary<string, object> d &&
+                        d.TryGetValue("role", out var r) && r.ToString() == "assistant"))
+                        continue;
+
                     bool nextIsToolResult = false;
                     if (i + 1 < history.Count && history[i + 1] is Dictionary<string, object> nextDict &&
                         nextDict.TryGetValue("role", out var nextRole) && nextRole.ToString() == "user" &&
@@ -587,20 +600,20 @@ Für welche Plattform soll die App entwickelt werden? Web, Mobile oder Desktop?
                         });
                     }
 
-                    if (!nextIsToolResult && history[i] is Dictionary<string, object> d &&
-                        d.TryGetValue("role", out var r) && r.ToString() == "assistant")
+                    if (!nextIsToolResult)
                     {
                         insertPositions.Add(i + 1);
+                        break;
                     }
                 }
             }
 
-            // Von hinten nach vorne einfügen, damit Indizes nicht verschoben werden
-            for (int j = insertPositions.Count - 1; j >= 0; j--)
+            // Deduplizieren und von hinten nach vorne einfügen, damit Indizes nicht verschoben werden
+            insertPositions = insertPositions.Distinct().OrderByDescending(x => x).ToList();
+            foreach (int insertPos in insertPositions)
             {
-                var pos = insertPositions[j];
-                history.Insert(pos, reminderAssistant);
-                history.Insert(pos, reminderUser);
+                history.Insert(insertPos, reminderAssistant);
+                history.Insert(insertPos, reminderUser);
             }
         }
 
diff --git a/wwwroot/css/chat.css b/wwwroot/css/chat.css
index 06dcfe9..9db48ce 100644
--- a/wwwroot/css/chat.css
+++ b/wwwroot/css/chat.css
@@ -874,6 +874,23 @@
   padding: 2em;
 }
 
+/* Payload Preview Modal */
+
+.payload-preview-modal {
+  max-width: 90vw;
+}
+
+.payload-json {
+  font-family: var(--mono);
+  white-space: pre-wrap;
+  word-break: break-all;
+  margin: 0;
+  padding: var(--box-padding);
+  background: var(--f3-bg);
+  border-radius: var(--border-radius);
+  border: var(--border-width) solid var(--f2-border);
+}
+
 /* Command Output Modal */
 
 .cmd-output-modal {
@@ -1276,7 +1293,7 @@
 /* ── OpenClaw Import Modal ── */
 
 .openclaw-import-modal {
-  max-width: 700px;
+  max-width: var(--modal-width);
 }
 
 .openclaw-hint {
@@ -1314,8 +1331,8 @@
 }
 
 .openclaw-session-id {
-  font-family: var(--mono-font);
-  font-size: var(--small-font-size);
+  font-family: var(--mono);
+  font-size: var(--mono-size);
   color: var(--primary);
   font-weight: 600;
 }
diff --git a/wwwroot/index.html b/wwwroot/index.html
index 7efbfd5..4ebafbf 100644
--- a/wwwroot/index.html
+++ b/wwwroot/index.html
@@ -386,6 +386,7 @@
         <div class="header-menu-dropdown" id="chatMenuDropdown" hidden>
           <button class="header-menu-item" id="remoteBtn"><i class="fa fa-desktop"></i> Remote-Verbindungen</button>
           <button class="header-menu-item" id="systemPromptBtn">System-Prompt anzeigen</button>
+          <button class="header-menu-item" id="payloadPreviewBtn">Payload anzeigen</button>
           <button class="header-menu-item" id="archiveBtn">Archivieren</button>
         </div>
       </div>
diff --git a/wwwroot/js/api.js b/wwwroot/js/api.js
index 02293ed..1d6e88c 100644
--- a/wwwroot/js/api.js
+++ b/wwwroot/js/api.js
@@ -111,6 +111,11 @@ function apiGetSystemPromptBlocks(sessionId, planMode) {
   return _get(url);
 }
 
+function apiGetPayloadPreview(sessionId, planMode) {
+  var url = '/api/sessions/' + sessionId + '/payload-preview' + (planMode ? '?planMode=true' : '');
+  return _get(url);
+}
+
 function apiIsStreaming(sessionId) { return _get('/api/sessions/' + sessionId + '/streaming'); }
 function apiGitStatus(sessionId) { return _get('/api/sessions/' + sessionId + '/git-status', null); }
 
diff --git a/wwwroot/js/modals.js b/wwwroot/js/modals.js
index e1dc498..e81a191 100644
--- a/wwwroot/js/modals.js
+++ b/wwwroot/js/modals.js
@@ -76,6 +76,26 @@ async function showSystemPromptModal(sessionId) {
   }
 }
 
+// ── Payload Preview Modal ──
+
+async function showPayloadPreviewModal(sessionId) {
+  const { body } = _createModal('Payload Preview', { modal: 'payload-preview-modal' });
+  body.innerHTML = '<div class="sp-loading">Laden...</div>';
+
+  try {
+    var planMode = typeof _planModeActive !== 'undefined' && _planModeActive;
+    var payload = await apiGetPayloadPreview(sessionId, planMode);
+    body.innerHTML = '';
+
+    var pre = document.createElement('pre');
+    pre.className = 'payload-json';
+    pre.textContent = JSON.stringify(payload, null, 2);
+    body.appendChild(pre);
+  } catch (e) {
+    body.innerHTML = '<div class="sp-loading text-danger">Fehler beim Laden des Payloads</div>';
+  }
+}
+
 // ── Command Output Modal ──
 
 function showCommandOutputModal(name, command, result) {
diff --git a/wwwroot/js/pages/chat-page.js b/wwwroot/js/pages/chat-page.js
index f57d297..162e698 100644
--- a/wwwroot/js/pages/chat-page.js
+++ b/wwwroot/js/pages/chat-page.js
@@ -416,6 +416,13 @@ registerPage('chat', {
       showSystemPromptModal(sessionId);
     });
 
+    // Payload anzeigen
+    const payloadPreviewBtn = document.getElementById('payloadPreviewBtn');
+    if (payloadPreviewBtn) payloadPreviewBtn.addEventListener('click', () => {
+      if (chatMenuDropdown) chatMenuDropdown.hidden = true;
+      showPayloadPreviewModal(sessionId);
+    });
+
     // Archivieren
     const archiveBtn = document.getElementById('archiveBtn');
     if (archiveBtn) archiveBtn.addEventListener('click', () => {