Add Anthropic prompt caching (direct + via OpenRouter)

Caches the system prompt/tools and growing conversation history via
cache_control breakpoints, cutting cost and latency on repeated turns.
Covers both the regular chat path and the tool-calling loop
(chatWithToolMessages), which has its own request-building code and was
initially missed. Cost calculation now accounts for cache write/read
pricing instead of treating all input tokens as full price. Verified
live: cache reads grow turn-over-turn in oAI.log.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -4,6 +4,7 @@
 
 ## User settings
 xcuserdata/
+xcshareddata/
 
 ## compatibility with Xcode 8 and earlier (ignoring not required starting Xcode 9)
 *.xcscmblueprint

DEVELOPMENT.md

@@ -72,17 +72,6 @@ oAI/
 
 ## Building
 
-### Build Scripts
-
-| Script | Architecture | Output |
-|--------|-------------|--------|
-| `build.sh` | Apple Silicon (arm64) | Installs directly to `/Applications` |
-| `build-dmg.sh` | Apple Silicon (arm64) | `oAI-<version>-AppleSilicon.dmg` on Desktop |
-| `build-dmg-universal.sh` | Universal (arm64 + x86_64) | `oAI-<version>-Universal.dmg` on Desktop |
-| `build_nb/sv/da/de/en.sh` | Apple Silicon (arm64) | Build + launch in specific language |
-
-All scripts: find Developer ID cert, clean-build via `xcodebuild`, re-sign with `codesign --options runtime --timestamp`, verify. Version is read from `MARKETING_VERSION` in `project.pbxproj`.
-
 ### Manual Build Commands
 
 ```bash

README.md

@@ -332,9 +332,6 @@ This means you are free to use, study, modify, and distribute oAI, but any modif
 
 See [LICENSE](LICENSE) for the full license text, or visit [gnu.org/licenses/agpl-3.0](https://www.gnu.org/licenses/agpl-3.0.html).
 
-## Development
-
-See [DEVELOPMENT.md](DEVELOPMENT.md) for project structure, build scripts, database schema, and contribution guidelines.
 
 ## Author
 
@@ -344,9 +341,6 @@ See [DEVELOPMENT.md](DEVELOPMENT.md) for project structure, build scripts, datab
 - Blog: [https://blog.rune.pm](https://blog.rune.pm)
 - Gitlab.pm: [@rune](https://gitlab.pm/rune)
 
-## Contributing
-
-Contributions are welcome! See [DEVELOPMENT.md](DEVELOPMENT.md) for build instructions and project structure.
 
 ---
 

oAI.xcodeproj/project.pbxproj

@@ -279,11 +279,11 @@
 				"INFOPLIST_KEY_UIStatusBarStyle[sdk=iphonesimulator*]" = UIStatusBarStyleDefault;
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
-				IPHONEOS_DEPLOYMENT_TARGET = 26.2;
+				IPHONEOS_DEPLOYMENT_TARGET = 27.0;
 				LD_RUNPATH_SEARCH_PATHS = "@executable_path/Frameworks";
 				"LD_RUNPATH_SEARCH_PATHS[sdk=macosx*]" = "@executable_path/../Frameworks";
-				MACOSX_DEPLOYMENT_TARGET = 26.2;
+				MACOSX_DEPLOYMENT_TARGET = 27.0;
-				MARKETING_VERSION = 2.3.9;
+				MARKETING_VERSION = 2.4.0;
 				PRODUCT_BUNDLE_IDENTIFIER = com.oai.oAI;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				REGISTER_APP_GROUPS = YES;
@@ -323,11 +323,11 @@
 				"INFOPLIST_KEY_UIStatusBarStyle[sdk=iphonesimulator*]" = UIStatusBarStyleDefault;
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
-				IPHONEOS_DEPLOYMENT_TARGET = 26.2;
+				IPHONEOS_DEPLOYMENT_TARGET = 27.0;
 				LD_RUNPATH_SEARCH_PATHS = "@executable_path/Frameworks";
 				"LD_RUNPATH_SEARCH_PATHS[sdk=macosx*]" = "@executable_path/../Frameworks";
-				MACOSX_DEPLOYMENT_TARGET = 26.2;
+				MACOSX_DEPLOYMENT_TARGET = 27.0;
-				MARKETING_VERSION = 2.3.9;
+				MARKETING_VERSION = 2.4.0;
 				PRODUCT_BUNDLE_IDENTIFIER = com.oai.oAI;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				REGISTER_APP_GROUPS = YES;

oAI.xcodeproj/xcshareddata/xcschemes/oAI.xcscheme

@@ -1,79 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<Scheme
-   LastUpgradeVersion = "2620"
-   version = "1.7">
-   <BuildAction
-      parallelizeBuildables = "YES"
-      buildImplicitDependencies = "YES"
-      buildArchitectures = "Automatic">
-      <BuildActionEntries>
-         <BuildActionEntry
-            buildForTesting = "YES"
-            buildForRunning = "YES"
-            buildForProfiling = "YES"
-            buildForArchiving = "YES"
-            buildForAnalyzing = "YES">
-            <BuildableReference
-               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "A550A6612F3B72EA00136F2B"
-               BuildableName = "oAI.app"
-               BlueprintName = "oAI"
-               ReferencedContainer = "container:oAI.xcodeproj">
-            </BuildableReference>
-         </BuildActionEntry>
-      </BuildActionEntries>
-   </BuildAction>
-   <TestAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES"
-      shouldAutocreateTestPlan = "YES">
-   </TestAction>
-   <LaunchAction
-      buildConfiguration = "Debug"
-      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
-      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      language = "nb"
-      launchStyle = "0"
-      useCustomWorkingDirectory = "NO"
-      ignoresPersistentStateOnLaunch = "NO"
-      debugDocumentVersioning = "YES"
-      debugServiceExtension = "internal"
-      allowLocationSimulation = "YES">
-      <BuildableProductRunnable
-         runnableDebuggingMode = "0">
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "A550A6612F3B72EA00136F2B"
-            BuildableName = "oAI.app"
-            BlueprintName = "oAI"
-            ReferencedContainer = "container:oAI.xcodeproj">
-         </BuildableReference>
-      </BuildableProductRunnable>
-   </LaunchAction>
-   <ProfileAction
-      buildConfiguration = "Release"
-      shouldUseLaunchSchemeArgsEnv = "YES"
-      savedToolIdentifier = ""
-      useCustomWorkingDirectory = "NO"
-      debugDocumentVersioning = "YES">
-      <BuildableProductRunnable
-         runnableDebuggingMode = "0">
-         <BuildableReference
-            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "A550A6612F3B72EA00136F2B"
-            BuildableName = "oAI.app"
-            BlueprintName = "oAI"
-            ReferencedContainer = "container:oAI.xcodeproj">
-         </BuildableReference>
-      </BuildableProductRunnable>
-   </ProfileAction>
-   <AnalyzeAction
-      buildConfiguration = "Debug">
-   </AnalyzeAction>
-   <ArchiveAction
-      buildConfiguration = "Release"
-      revealArchiveInOrganizer = "YES">
-   </ArchiveAction>
-</Scheme>

oAI/Assets.xcassets/AccentColor.colorset/Contents.json

@@ -0,0 +1,20 @@
+{
+  "colors" : [
+    {
+      "color" : {
+        "color-space" : "srgb",
+        "components" : {
+          "alpha" : "1.000",
+          "blue" : "0xCA",
+          "green" : "0x7A",
+          "red" : "0x0A"
+        }
+      },
+      "idiom" : "universal"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

oAI/Info.plist

@@ -6,5 +6,13 @@
         <string>oAI.help</string>
         <key>CFBundleHelpBookName</key>
         <string>oAI Help</string>
+        <key>CFBundleLocalizations</key>
+        <array>
+              <string>en</string>
+              <string>nb</string>
+              <string>da</string>
+              <string>de</string>
+              <string>sv</string>
+        </array>
   </dict>
   </plist>

oAI/Localizable.xcstrings

@@ -1,6 +1,13 @@
 {
   "sourceLanguage" : "en",
   "strings" : {
+    "·" : {
+      "comment" : "A separator between the message count and the date.",
+      "isCommentAutoGenerated" : true
+    },
+    "· %@" : {
+
+    },
     "(always used)" : {
       "localizations" : {
         "da" : {
@@ -432,6 +439,12 @@
           }
         }
       }
+    },
+    "^[%@ message](inflect: true)" : {
+
+    },
+    "^[%@ token](inflect: true)" : {
+
     },
     "© 2026 [Rune Olsen](https://blog.rune.pm)" : {
       "comment" : "A copyright notice with the copyright holder's name.",
@@ -521,6 +534,7 @@
     },
     "⌘N New • ⌘M Model • ⌘S Save" : {
       "comment" : "A hint that appears on macOS when using keyboard shortcuts.",
+      "extractionState" : "stale",
       "isCommentAutoGenerated" : true,
       "localizations" : {
         "da" : {
@@ -549,6 +563,10 @@
         }
       }
     },
+    "⚠️ Beta — Paperless integration is under active development. Some features may be incomplete or behave unexpectedly." : {
+      "comment" : "A warning displayed in the settings view.",
+      "isCommentAutoGenerated" : true
+    },
     "⚠️ Custom prompt active — only this prompt will be sent to the model." : {
       "localizations" : {
         "da" : {
@@ -894,6 +912,12 @@
           }
         }
       }
+    },
+    "🧠" : {
+
+    },
+    "1. Open Anytype → Settings → Integrations" : {
+
     },
     "1. Open Paperless-NGX → Settings → API Tokens" : {
       "comment" : "A step in the process of getting a Paperless-NGX API token.",
@@ -925,6 +949,10 @@
         }
       }
     },
+    "2. Create a new API key" : {
+      "comment" : "A step in the process of getting an API key from Anytype.",
+      "isCommentAutoGenerated" : true
+    },
     "2. Create or copy your token" : {
       "comment" : "A step in the process of getting a Paperless-NGX API token.",
       "isCommentAutoGenerated" : true,
@@ -1132,6 +1160,9 @@
           }
         }
       }
+    },
+    "Agent" : {
+
     },
     "Agent Skills" : {
       "localizations" : {
@@ -1160,6 +1191,9 @@
           }
         }
       }
+    },
+    "Agents" : {
+
     },
     "Allow Shell Command?" : {
       "comment" : "A title for a modal that asks the user if they want to allow a shell command.",
@@ -1566,6 +1600,9 @@
           }
         }
       }
+    },
+    "Category" : {
+
     },
     "Changing these values affects how the AI generates responses. The defaults work well for most use cases." : {
       "localizations" : {
@@ -1654,6 +1691,9 @@
           }
         }
       }
+    },
+    "Choose an agent from the list to view details and run history" : {
+
     },
     "Clear All" : {
       "comment" : "A button to clear all email activity logs.",
@@ -1918,6 +1958,9 @@
           }
         }
       }
+    },
+    "Cost" : {
+
     },
     "Cost Examples" : {
       "comment" : "A heading for the cost examples of a model.",
@@ -2092,6 +2135,9 @@
           }
         }
       }
+    },
+    "Disabled" : {
+
     },
     "Each command will require your approval before running." : {
       "localizations" : {
@@ -2468,6 +2514,12 @@
           }
         }
       }
+    },
+    "Filter by Category" : {
+
+    },
+    "Generate an API key in your Jarvis settings and paste it above." : {
+
     },
     "Google (Gemini embedding)" : {
       "localizations" : {
@@ -2526,6 +2578,12 @@
           }
         }
       }
+    },
+    "High (~80%)" : {
+
+    },
+    "How to get your API key:" : {
+
     },
     "How to get your API token:" : {
       "comment" : "A heading for a section that describes how to get your API token.",
@@ -2640,6 +2698,9 @@
           }
         }
       }
+    },
+    "Input" : {
+
     },
     "Large files inflate the system prompt and may hit token limits." : {
       "comment" : "A warning displayed when a user adds a large file to a skill.",
@@ -2726,6 +2787,9 @@
           }
         }
       }
+    },
+    "Low (~20%)" : {
+
     },
     "Lowercase letters, numbers, and hyphens only. No spaces." : {
       "comment" : "A description of the format of a shortcut's command.",
@@ -2842,6 +2906,9 @@
           }
         }
       }
+    },
+    "Medium (~50%)" : {
+
     },
     "messages" : {
       "localizations" : {
@@ -2870,6 +2937,9 @@
           }
         }
       }
+    },
+    "Minimal (~10%)" : {
+
     },
     "Model Context Protocol" : {
       "localizations" : {
@@ -2928,6 +2998,9 @@
           }
         }
       }
+    },
+    "Model thinks internally but reasoning is not shown in chat" : {
+
     },
     "Multi-provider AI chat client" : {
       "comment" : "A description of oAI.",
@@ -3018,6 +3091,9 @@
           }
         }
       }
+    },
+    "New Chat" : {
+
     },
     "No credit data available" : {
       "comment" : "A message displayed when there is no credit data available.",
@@ -3196,6 +3272,9 @@
           }
         }
       }
+    },
+    "No runs yet" : {
+
     },
     "No shortcuts yet" : {
       "comment" : "A message displayed when a user has no shortcuts.",
@@ -3347,6 +3426,10 @@
         }
       }
     },
+    "oAI v2.4 is the last version to support Intel Macs and Rosetta. Starting with macOS 28, oAI will require Apple Silicon. Consider upgrading your Mac to continue receiving updates." : {
+      "comment" : "A warning that Intel Macs are no longer supported.",
+      "isCommentAutoGenerated" : true
+    },
     "Ollama (Local)" : {
       "comment" : "A label displayed above the credits information for the local Ollie.",
       "isCommentAutoGenerated" : true,
@@ -3574,6 +3657,9 @@
           }
         }
       }
+    },
+    "OpenRouter Balance" : {
+
     },
     "OpenRouter Credits" : {
       "comment" : "A heading for the user's OpenRouter credits.",
@@ -3604,6 +3690,12 @@
           }
         }
       }
+    },
+    "Output" : {
+
+    },
+    "Prompt" : {
+
     },
     "Read access (always enabled)" : {
       "localizations" : {
@@ -3632,6 +3724,9 @@
           }
         }
       }
+    },
+    "Reasoning" : {
+
     },
     "Remote: %@" : {
       "localizations" : {
@@ -3690,6 +3785,12 @@
           }
         }
       }
+    },
+    "Run History" : {
+
+    },
+    "Run some agents to see usage statistics" : {
+
     },
     "Running locally — no credits needed!" : {
       "comment" : "A message displayed when using an on-device LLM like the one provided by the `.ollama` provider.",
@@ -3721,6 +3822,10 @@
         }
       }
     },
+    "Runs" : {
+      "comment" : "A column header for the number of runs.",
+      "isCommentAutoGenerated" : true
+    },
     "Security Recommendation" : {
       "localizations" : {
         "da" : {
@@ -3866,6 +3971,9 @@
           }
         }
       }
+    },
+    "Sort" : {
+
     },
     "SSH Key" : {
       "localizations" : {
@@ -4180,6 +4288,9 @@
           }
         }
       }
+    },
+    "Thinking…" : {
+
     },
     "This default prompt is always included to ensure accurate, helpful responses." : {
       "localizations" : {
@@ -4296,6 +4407,15 @@
           }
         }
       }
+    },
+    "Total" : {
+
+    },
+    "Total Credits" : {
+
+    },
+    "Total Used" : {
+
     },
     "Try adjusting your search or filters" : {
       "comment" : "A description of the error that occurs when no models match the user's search.",
@@ -4444,6 +4564,9 @@
           }
         }
       }
+    },
+    "Usage" : {
+
     },
     "Use @filename to attach files to your message" : {
       "comment" : "A description of how to attach files to a message.",
@@ -4565,6 +4688,7 @@
     },
     "v%@" : {
       "comment" : "A label showing the current version of oAI.",
+      "extractionState" : "stale",
       "isCommentAutoGenerated" : true,
       "localizations" : {
         "da" : {
@@ -4744,6 +4868,10 @@
           }
         }
       }
+    },
+    "β" : {
+      "comment" : "A beta badge.",
+      "isCommentAutoGenerated" : true
     }
   },
   "version" : "1.1"

oAI/Models/Conversation.swift

@@ -33,7 +33,7 @@ struct Conversation: Identifiable, Codable {
     var updatedAt: Date
     var primaryModel: String? // Primary model used in this conversation
 
-    init(
+    nonisolated init(
         id: UUID = UUID(),
         name: String,
         messages: [Message] = [],

oAI/Models/EmailLog.swift

@@ -44,7 +44,7 @@ struct EmailLog: Identifiable, Codable, Equatable {
     let responseTime: TimeInterval? // Time to generate response in seconds
     let modelId: String? // Model that handled the email
 
-    init(
+    nonisolated init(
         id: UUID = UUID(),
         timestamp: Date = Date(),
         sender: String,

oAI/Models/Message.swift

@@ -66,7 +66,7 @@ struct Message: Identifiable, Codable, Equatable {
     // Reasoning/thinking content (not persisted — in-memory only)
     var thinkingContent: String? = nil
 
-    init(
+    nonisolated init(
         id: UUID = UUID(),
         role: MessageRole,
         content: String,

oAI/Providers/AIProvider.swift

@@ -130,11 +130,23 @@ struct ChatResponse: Codable {
         let promptTokens: Int
         let completionTokens: Int
         let totalTokens: Int
+        let cacheCreationInputTokens: Int?
+        let cacheReadInputTokens: Int?
+
+        init(promptTokens: Int, completionTokens: Int, totalTokens: Int, cacheCreationInputTokens: Int? = nil, cacheReadInputTokens: Int? = nil) {
+            self.promptTokens = promptTokens
+            self.completionTokens = completionTokens
+            self.totalTokens = totalTokens
+            self.cacheCreationInputTokens = cacheCreationInputTokens
+            self.cacheReadInputTokens = cacheReadInputTokens
+        }
 
         enum CodingKeys: String, CodingKey {
             case promptTokens = "prompt_tokens"
             case completionTokens = "completion_tokens"
             case totalTokens = "total_tokens"
+            case cacheCreationInputTokens = "cache_creation_input_tokens"
+            case cacheReadInputTokens = "cache_read_input_tokens"
         }
     }
 

oAI/Providers/AnthropicProvider.swift

@@ -77,6 +77,15 @@ class AnthropicProvider: AIProvider {
     /// falls back to prefix matching so newly-released model variants (e.g. "claude-sonnet-4-6-20260301")
     /// still inherit the correct pricing tier.
     private static let knownModels: [ModelInfo] = [
+        // Claude Fable 5
+        ModelInfo(
+            id: "claude-fable-5",
+            name: "Claude Fable 5",
+            description: "Anthropic's creative and storytelling model",
+            contextLength: 200_000,
+            pricing: .init(prompt: 10.0, completion: 50.0),
+            capabilities: .init(vision: true, tools: true, online: true)
+        ),
         // Claude 4.x series
         ModelInfo(
             id: "claude-opus-4-6",
@@ -173,6 +182,7 @@ class AnthropicProvider: AIProvider {
     /// Pricing tiers used for fuzzy fallback matching on unknown model IDs.
     /// Keyed by model name prefix (longest match wins).
     private static let pricingFallback: [(prefix: String, prompt: Double, completion: Double)] = [
+        ("claude-fable",  10.0, 50.0),
         ("claude-opus",   15.0, 75.0),
         ("claude-sonnet",  3.0, 15.0),
         ("claude-haiku",   0.80, 4.0),
@@ -356,6 +366,19 @@ class AnthropicProvider: AIProvider {
             }
         }
 
+        // Mark the last message with a cache breakpoint so the next loop
+        // iteration (or next turn) can reuse everything up through this one.
+        if var lastMessage = conversationMessages.popLast() {
+            if let content = lastMessage["content"] as? String {
+                lastMessage["content"] = [["type": "text", "text": content, "cache_control": ["type": "ephemeral"]]]
+            } else if var blocks = lastMessage["content"] as? [[String: Any]], var lastBlock = blocks.popLast() {
+                lastBlock["cache_control"] = ["type": "ephemeral"]
+                blocks.append(lastBlock)
+                lastMessage["content"] = blocks
+            }
+            conversationMessages.append(lastMessage)
+        }
+
         var body: [String: Any] = [
             "model": model,
             "messages": conversationMessages,
@@ -363,7 +386,9 @@ class AnthropicProvider: AIProvider {
             "stream": false
         ]
         if let systemText = systemText {
-            body["system"] = systemText
+            // Array form carries a cache breakpoint; also covers tools, which
+            // render before system in Anthropic's prefix order.
+            body["system"] = [["type": "text", "text": systemText, "cache_control": ["type": "ephemeral"]]]
         }
         if let temperature = temperature {
             body["temperature"] = temperature
@@ -430,6 +455,8 @@ class AnthropicProvider: AIProvider {
                     var currentId = ""
                     var currentModel = request.model
                     var inputTokens = 0
+                    var cacheCreationTokens: Int? = nil
+                    var cacheReadTokens: Int? = nil
 
                     for try await line in bytes.lines {
                         // Anthropic SSE: "event: ..." and "data: {...}"
@@ -449,6 +476,11 @@ class AnthropicProvider: AIProvider {
                                 currentModel = message["model"] as? String ?? request.model
                                 if let usageDict = message["usage"] as? [String: Any] {
                                     inputTokens = usageDict["input_tokens"] as? Int ?? 0
+                                    cacheCreationTokens = usageDict["cache_creation_input_tokens"] as? Int
+                                    cacheReadTokens = usageDict["cache_read_input_tokens"] as? Int
+                                    if cacheCreationTokens != nil || cacheReadTokens != nil {
+                                        Log.api.info("Anthropic stream cache usage: input=\(inputTokens), created=\(cacheCreationTokens ?? 0), read=\(cacheReadTokens ?? 0)")
+                                    }
                                 }
                             }
 
@@ -472,7 +504,13 @@ class AnthropicProvider: AIProvider {
                             var usage: ChatResponse.Usage? = nil
                             if let usageDict = event["usage"] as? [String: Any] {
                                 let outputTokens = usageDict["output_tokens"] as? Int ?? 0
-                                usage = ChatResponse.Usage(promptTokens: inputTokens, completionTokens: outputTokens, totalTokens: inputTokens + outputTokens)
+                                usage = ChatResponse.Usage(
+                                    promptTokens: inputTokens,
+                                    completionTokens: outputTokens,
+                                    totalTokens: inputTokens + outputTokens,
+                                    cacheCreationInputTokens: cacheCreationTokens,
+                                    cacheReadInputTokens: cacheReadTokens
+                                )
                             }
                             continuation.yield(StreamChunk(
                                 id: currentId,
@@ -582,6 +620,19 @@ class AnthropicProvider: AIProvider {
             }
         }
 
+        // Mark the last message with a cache breakpoint so the next turn can
+        // reuse everything up through this one as a cached prefix.
+        if var lastMessage = apiMessages.popLast() {
+            if let content = lastMessage["content"] as? String {
+                lastMessage["content"] = [["type": "text", "text": content, "cache_control": ["type": "ephemeral"]]]
+            } else if var blocks = lastMessage["content"] as? [[String: Any]], var lastBlock = blocks.popLast() {
+                lastBlock["cache_control"] = ["type": "ephemeral"]
+                blocks.append(lastBlock)
+                lastMessage["content"] = blocks
+            }
+            apiMessages.append(lastMessage)
+        }
+
         var body: [String: Any] = [
             "model": request.model,
             "messages": apiMessages,
@@ -590,7 +641,10 @@ class AnthropicProvider: AIProvider {
         ]
 
         if let systemText = systemText {
-            body["system"] = systemText
+            // Array form (rather than a plain string) carries a cache breakpoint.
+            // Per Anthropic's render order (tools -> system -> messages), this
+            // single breakpoint caches the tool definitions too.
+            body["system"] = [["type": "text", "text": systemText, "cache_control": ["type": "ephemeral"]]]
         }
         if let temperature = request.temperature {
             body["temperature"] = temperature
@@ -665,6 +719,11 @@ class AnthropicProvider: AIProvider {
         let usageDict = json["usage"] as? [String: Any]
         let inputTokens = usageDict?["input_tokens"] as? Int ?? 0
         let outputTokens = usageDict?["output_tokens"] as? Int ?? 0
+        let cacheCreationTokens = usageDict?["cache_creation_input_tokens"] as? Int
+        let cacheReadTokens = usageDict?["cache_read_input_tokens"] as? Int
+        if cacheCreationTokens != nil || cacheReadTokens != nil {
+            Log.api.info("Anthropic cache usage: input=\(inputTokens), created=\(cacheCreationTokens ?? 0), read=\(cacheReadTokens ?? 0)")
+        }
 
         return ChatResponse(
             id: id,
@@ -675,7 +734,9 @@ class AnthropicProvider: AIProvider {
             usage: ChatResponse.Usage(
                 promptTokens: inputTokens,
                 completionTokens: outputTokens,
-                totalTokens: inputTokens + outputTokens
+                totalTokens: inputTokens + outputTokens,
+                cacheCreationInputTokens: cacheCreationTokens,
+                cacheReadInputTokens: cacheReadTokens
             ),
             created: Date(),
             toolCalls: toolCalls.isEmpty ? nil : toolCalls

oAI/Providers/OpenRouterModels.swift

@@ -48,6 +48,11 @@ struct OpenRouterChatRequest: Codable {
     let toolChoice: String?
     let modalities: [String]?
     let reasoning: ReasoningAPIConfig?
+    let cacheControl: CacheControl?
+
+    struct CacheControl: Codable {
+        let type: String
+    }
 
     struct APIMessage: Codable {
         let role: String
@@ -138,6 +143,7 @@ struct OpenRouterChatRequest: Codable {
         case toolChoice = "tool_choice"
         case modalities
         case reasoning
+        case cacheControl = "cache_control"
     }
 }
 
@@ -225,11 +231,23 @@ struct OpenRouterChatResponse: Codable {
         let promptTokens: Int
         let completionTokens: Int
         let totalTokens: Int
+        let promptTokensDetails: PromptTokensDetails?
+
+        struct PromptTokensDetails: Codable {
+            let cachedTokens: Int?
+            let cacheWriteTokens: Int?
+
+            enum CodingKeys: String, CodingKey {
+                case cachedTokens = "cached_tokens"
+                case cacheWriteTokens = "cache_write_tokens"
+            }
+        }
 
         enum CodingKeys: String, CodingKey {
             case promptTokens = "prompt_tokens"
             case completionTokens = "completion_tokens"
             case totalTokens = "total_tokens"
+            case promptTokensDetails = "prompt_tokens_details"
         }
     }
 }

oAI/Providers/OpenRouterProvider.swift

@@ -198,6 +198,11 @@ class OpenRouterProvider: AIProvider {
         }
         if let maxTokens = maxTokens { body["max_tokens"] = maxTokens }
         if let temperature = temperature { body["temperature"] = temperature }
+        // Anthropic models require an explicit cache_control opt-in on OpenRouter;
+        // other providers cache automatically.
+        if model.hasPrefix("anthropic/") {
+            body["cache_control"] = ["type": "ephemeral"]
+        }
 
         var urlRequest = URLRequest(url: url)
         urlRequest.httpMethod = "POST"
@@ -388,6 +393,12 @@ class OpenRouterProvider: AIProvider {
             ReasoningAPIConfig(effort: $0.effort, exclude: $0.exclude ? true : nil)
         }
 
+        // Anthropic models require an explicit cache_control opt-in on OpenRouter;
+        // other providers (OpenAI, DeepSeek, Gemini, Grok, etc.) cache automatically.
+        let cacheControl: OpenRouterChatRequest.CacheControl? = effectiveModel.hasPrefix("anthropic/")
+            ? .init(type: "ephemeral")
+            : nil
+
         return OpenRouterChatRequest(
             model: effectiveModel,
             messages: apiMessages,
@@ -398,7 +409,8 @@ class OpenRouterProvider: AIProvider {
             tools: request.tools,
             toolChoice: request.tools != nil ? "auto" : nil,
             modalities: request.imageGeneration ? ["text", "image"] : nil,
-            reasoning: reasoningConfig
+            reasoning: reasoningConfig,
+            cacheControl: cacheControl
         )
     }
     
@@ -416,6 +428,11 @@ class OpenRouterProvider: AIProvider {
         let allImages = topLevelImages + blockImages
         let images: [Data]? = allImages.isEmpty ? nil : allImages
 
+        if let details = apiResponse.usage?.promptTokensDetails,
+           details.cachedTokens != nil || details.cacheWriteTokens != nil {
+            Log.api.info("OpenRouter cache usage: model=\(apiResponse.model), created=\(details.cacheWriteTokens ?? 0), read=\(details.cachedTokens ?? 0)")
+        }
+
         return ChatResponse(
             id: apiResponse.id,
             model: apiResponse.model,
@@ -426,7 +443,9 @@ class OpenRouterProvider: AIProvider {
                 ChatResponse.Usage(
                     promptTokens: usage.promptTokens,
                     completionTokens: usage.completionTokens,
-                    totalTokens: usage.totalTokens
+                    totalTokens: usage.totalTokens,
+                    cacheCreationInputTokens: usage.promptTokensDetails?.cacheWriteTokens,
+                    cacheReadInputTokens: usage.promptTokensDetails?.cachedTokens
                 )
             },
             created: Date(timeIntervalSince1970: TimeInterval(apiResponse.created)),
@@ -446,6 +465,11 @@ class OpenRouterProvider: AIProvider {
         let allImages = topLevelImages + blockImages
         let images: [Data]? = allImages.isEmpty ? nil : allImages
 
+        if let details = apiChunk.usage?.promptTokensDetails,
+           details.cachedTokens != nil || details.cacheWriteTokens != nil {
+            Log.api.info("OpenRouter stream cache usage: model=\(apiChunk.model), created=\(details.cacheWriteTokens ?? 0), read=\(details.cachedTokens ?? 0)")
+        }
+
         return StreamChunk(
             id: apiChunk.id,
             model: apiChunk.model,
@@ -460,7 +484,9 @@ class OpenRouterProvider: AIProvider {
                 ChatResponse.Usage(
                     promptTokens: usage.promptTokens,
                     completionTokens: usage.completionTokens,
-                    totalTokens: usage.totalTokens
+                    totalTokens: usage.totalTokens,
+                    cacheCreationInputTokens: usage.promptTokensDetails?.cacheWriteTokens,
+                    cacheReadInputTokens: usage.promptTokensDetails?.cachedTokens
                 )
             }
         )

oAI/Services/ConversationMergeService.swift

@@ -0,0 +1,193 @@
+//
+//  ConversationMergeService.swift
+//  oAI
+//
+//  Combine multiple saved conversations into one (simple concatenation or AI-assisted merge)
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+// Copyright (C) 2026 Rune Olsen
+//
+// This file is part of oAI.
+//
+// oAI is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// oAI is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General
+// Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public
+// License along with oAI. If not, see <https://www.gnu.org/licenses/>.
+
+
+import Foundation
+import os
+
+enum CombineMode: String, Sendable {
+    case simple
+    case ai
+}
+
+enum MergeError: LocalizedError {
+    case tooFewConversations
+    case noDefaultModel
+    case noAPIKey
+    case invalidAIResponse(String)
+
+    var errorDescription: String? {
+        switch self {
+        case .tooFewConversations:
+            return "Select at least two conversations to combine."
+        case .noDefaultModel:
+            return "No default model is configured. Set one in Settings → General → Default Model."
+        case .noAPIKey:
+            return "No API key configured for the default provider. Add one in Settings."
+        case .invalidAIResponse(let snippet):
+            return "The model's response could not be parsed into a conversation: \(snippet)"
+        }
+    }
+}
+
+enum ConversationMergeService {
+
+    static func merge(
+        conversationIds: [UUID],
+        name: String,
+        mode: CombineMode,
+        deleteOriginals: Bool
+    ) async throws -> Conversation {
+        guard conversationIds.count >= 2 else {
+            throw MergeError.tooFewConversations
+        }
+
+        let sources: [(Conversation, [Message])] = try conversationIds.compactMap { id in
+            try DatabaseService.shared.loadConversation(id: id)
+        }
+
+        // The model used in the merged conversation should reflect the most recently used
+        // model across the *source* conversations — never the model that performed the merge.
+        let latestModelId = sources
+            .flatMap { $0.1 }
+            .filter { $0.modelId != nil }
+            .max { $0.timestamp < $1.timestamp }?
+            .modelId
+
+        let mergedMessages: [Message]
+        switch mode {
+        case .simple:
+            mergedMessages = simpleMerge(sources)
+        case .ai:
+            mergedMessages = try await aiMerge(sources)
+        }
+
+        let newConversation = try DatabaseService.shared.saveConversation(
+            id: UUID(),
+            name: name,
+            messages: mergedMessages,
+            primaryModel: latestModelId
+        )
+
+        if deleteOriginals {
+            for id in conversationIds {
+                _ = try? DatabaseService.shared.deleteConversation(id: id)
+            }
+        }
+
+        Log.db.info("Combined \(conversationIds.count) conversations into '\(name)' (mode: \(mode.rawValue), deleteOriginals: \(deleteOriginals))")
+
+        return newConversation
+    }
+
+    private static func simpleMerge(_ sources: [(Conversation, [Message])]) -> [Message] {
+        sources.flatMap { $0.1 }.sorted { $0.timestamp < $1.timestamp }
+    }
+
+    private struct MergedTurn: Codable {
+        let role: String
+        let content: String
+    }
+
+    private static func aiMerge(_ sources: [(Conversation, [Message])]) async throws -> [Message] {
+        let settings = SettingsService.shared
+        guard let modelId = settings.defaultModel, !modelId.isEmpty else {
+            throw MergeError.noDefaultModel
+        }
+        guard let provider = ProviderRegistry.shared.getProvider(for: settings.defaultProvider) else {
+            throw MergeError.noAPIKey
+        }
+
+        let transcript = sources.map { conversation, messages -> String in
+            let body = messages.map { msg -> String in
+                let label = msg.role == .user ? "**User:**" : "**Assistant:**"
+                return "\(label) \(msg.content)"
+            }.joined(separator: "\n\n")
+            return "### Conversation: \(conversation.name)\n\n\(body)"
+        }.joined(separator: "\n\n---\n\n")
+
+        let mergePrompt = """
+        Merge the following saved conversation transcripts into a single, coherent conversation. \
+        Remove redundant or duplicate exchanges, keep the most informative answer when sources overlap, \
+        preserve important details from each source, and do not invent facts that were not in the originals.
+
+        Respond with ONLY a JSON array of message objects in logical order, each in the form \
+        {"role": "user" or "assistant", "content": "..."}. Do not include any text outside the JSON array.
+
+        \(transcript)
+        """
+
+        let request = ChatRequest(
+            messages: [Message(role: .user, content: mergePrompt)],
+            model: modelId,
+            stream: false,
+            maxTokens: 4000,
+            temperature: 0.3,
+            topP: nil,
+            systemPrompt: "You are a helpful assistant that merges chat conversation transcripts into one clean, coherent conversation.",
+            tools: nil,
+            onlineMode: false,
+            imageGeneration: false
+        )
+
+        let response: ChatResponse
+        do {
+            response = try await provider.chat(request: request)
+        } catch {
+            Log.api.error("Conversation merge AI call failed: \(error.localizedDescription)")
+            throw error
+        }
+
+        let turns = try parseTurns(from: response.content)
+
+        // modelId intentionally left nil here: these messages are a synthesized composite,
+        // not output from a single source model. The conversation's primaryModel (set by the
+        // caller from the source conversations) is what drives the model shown in the list.
+        let base = Date()
+        return turns.enumerated().map { index, turn in
+            Message(
+                role: turn.role == "user" ? .user : .assistant,
+                content: turn.content,
+                timestamp: base.addingTimeInterval(TimeInterval(index))
+            )
+        }
+    }
+
+    private static func parseTurns(from raw: String) throws -> [MergedTurn] {
+        var text = raw.trimmingCharacters(in: .whitespacesAndNewlines)
+        if text.hasPrefix("```") {
+            text = text.components(separatedBy: "\n").dropFirst().joined(separator: "\n")
+            if text.hasSuffix("```") {
+                text = String(text.dropLast(3))
+            }
+            text = text.trimmingCharacters(in: .whitespacesAndNewlines)
+        }
+        guard let data = text.data(using: .utf8),
+              let turns = try? JSONDecoder().decode([MergedTurn].self, from: data),
+              !turns.isEmpty else {
+            throw MergeError.invalidAIResponse(String(raw.prefix(200)))
+        }
+        return turns
+    }
+}

oAI/Services/DatabaseService.swift

@@ -134,15 +134,29 @@ final class DatabaseService: Sendable {
     nonisolated static let shared = DatabaseService()
 
     private let dbQueue: DatabaseQueue
-    private let isoFormatter: ISO8601DateFormatter
 
     // Command history limit - keep most recent 5000 entries
-    private static let maxHistoryEntries = 5000
+    private nonisolated static let maxHistoryEntries = 5000
+
+    // ISO8601DateFormatter is @MainActor in macOS 27. Use Date.ISO8601FormatStyle (value type, Sendable).
+    private nonisolated static let isoStyle = Date.ISO8601FormatStyle(
+        dateSeparator: .dash,
+        dateTimeSeparator: .standard,
+        timeSeparator: .colon,
+        timeZoneSeparator: .colon,
+        includingFractionalSeconds: true,
+        timeZone: .gmt
+    )
+
+    private nonisolated static func isoString(from date: Date) -> String {
+        isoStyle.format(date)
+    }
+
+    private nonisolated static func isoDate(from string: String) -> Date? {
+        (try? isoStyle.parse(string)) ?? (try? Date(string, strategy: .iso8601))
+    }
 
     nonisolated private init() {
-        isoFormatter = ISO8601DateFormatter()
-        isoFormatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
-
         let fileManager = FileManager.default
         let appSupport = fileManager.urls(for: .applicationSupportDirectory, in: .userDomainMask).first!
         let dbDirectory = appSupport.appendingPathComponent("oAI", isDirectory: true)
@@ -156,7 +170,7 @@ final class DatabaseService: Sendable {
         try! migrator.migrate(dbQueue)
     }
 
-    private var migrator: DatabaseMigrator {
+    private nonisolated var migrator: DatabaseMigrator {
         var migrator = DatabaseMigrator()
 
         migrator.registerMigration("v1") { db in
@@ -375,7 +389,7 @@ final class DatabaseService: Sendable {
     nonisolated func saveConversation(id: UUID, name: String, messages: [Message], primaryModel: String?) throws -> Conversation {
         Log.db.info("Saving conversation '\(name)' with \(messages.count) messages (primaryModel: \(primaryModel ?? "none"))")
         let now = Date()
-        let nowString = isoFormatter.string(from: now)
+        let nowString = Self.isoString(from: now)
 
         let convRecord = ConversationRecord(
             id: id.uuidString,
@@ -394,7 +408,7 @@ final class DatabaseService: Sendable {
                 content: msg.content,
                 tokens: msg.tokens,
                 cost: msg.cost,
-                timestamp: isoFormatter.string(from: msg.timestamp),
+                timestamp: Self.isoString(from: msg.timestamp),
                 sortOrder: index,
                 modelId: msg.modelId
             )
@@ -420,7 +434,7 @@ final class DatabaseService: Sendable {
 
     /// Update an existing conversation in-place: rename it, replace all its messages.
     nonisolated func updateConversation(id: UUID, name: String, messages: [Message], primaryModel: String?) throws {
-        let nowString = isoFormatter.string(from: Date())
+        let nowString = Self.isoString(from: Date())
 
         let messageRecords = messages.enumerated().compactMap { index, msg -> MessageRecord? in
             guard msg.role != .system else { return nil }
@@ -431,7 +445,7 @@ final class DatabaseService: Sendable {
                 content: msg.content,
                 tokens: msg.tokens,
                 cost: msg.cost,
-                timestamp: isoFormatter.string(from: msg.timestamp),
+                timestamp: Self.isoString(from: msg.timestamp),
                 sortOrder: index,
                 modelId: msg.modelId
             )
@@ -466,7 +480,7 @@ final class DatabaseService: Sendable {
             let messages = messageRecords.compactMap { record -> Message? in
                 guard let msgId = UUID(uuidString: record.id),
                       let role = MessageRole(rawValue: record.role),
-                      let timestamp = self.isoFormatter.date(from: record.timestamp)
+                      let timestamp = Self.isoDate(from: record.timestamp)
                 else { return nil }
 
                 let starred = (try? MessageMetadataRecord.fetchOne(db, key: record.id))?.user_starred == 1
@@ -484,8 +498,8 @@ final class DatabaseService: Sendable {
             }
 
             guard let convId = UUID(uuidString: convRecord.id),
-                  let createdAt = self.isoFormatter.date(from: convRecord.createdAt),
+                  let createdAt = Self.isoDate(from: convRecord.createdAt),
-                  let updatedAt = self.isoFormatter.date(from: convRecord.updatedAt)
+                  let updatedAt = Self.isoDate(from: convRecord.updatedAt)
             else { return nil }
 
             let conversation = Conversation(
@@ -509,8 +523,8 @@ final class DatabaseService: Sendable {
 
             return records.compactMap { record -> Conversation? in
                 guard let id = UUID(uuidString: record.id),
-                      let createdAt = self.isoFormatter.date(from: record.createdAt),
+                      let createdAt = Self.isoDate(from: record.createdAt),
-                      let updatedAt = self.isoFormatter.date(from: record.updatedAt)
+                      let updatedAt = Self.isoDate(from: record.updatedAt)
                 else { return nil }
 
                 // Fetch message count without loading all messages
@@ -524,7 +538,7 @@ final class DatabaseService: Sendable {
                     .order(Column("sortOrder").desc)
                     .fetchOne(db)
 
-                let lastDate = lastMsg.flatMap { self.isoFormatter.date(from: $0.timestamp) } ?? updatedAt
+                let lastDate = lastMsg.flatMap { Self.isoDate(from: $0.timestamp) } ?? updatedAt
 
                 // Derive primary model: prefer the stored field, fall back to last message's modelId
                 let primaryModel = record.primaryModel ?? lastMsg?.modelId
@@ -574,7 +588,7 @@ final class DatabaseService: Sendable {
                 convRecord.name = name
             }
 
-            convRecord.updatedAt = self.isoFormatter.string(from: Date())
+            convRecord.updatedAt = Self.isoString(from: Date())
             try convRecord.update(db)
 
             if let messages = messages {
@@ -589,7 +603,7 @@ final class DatabaseService: Sendable {
                         content: msg.content,
                         tokens: msg.tokens,
                         cost: msg.cost,
-                        timestamp: self.isoFormatter.string(from: msg.timestamp),
+                        timestamp: Self.isoString(from: msg.timestamp),
                         sortOrder: index
                     )
                 }
@@ -610,7 +624,7 @@ final class DatabaseService: Sendable {
         let record = HistoryRecord(
             id: UUID().uuidString,
             input: input,
-            timestamp: isoFormatter.string(from: now)
+            timestamp: Self.isoString(from: now)
         )
 
         try? dbQueue.write { db in
@@ -643,7 +657,7 @@ final class DatabaseService: Sendable {
                 .fetchAll(db)
 
             return records.compactMap { record in
-                guard let date = isoFormatter.date(from: record.timestamp) else {
+                guard let date = Self.isoDate(from: record.timestamp) else {
                     return nil
                 }
                 return (input: record.input, timestamp: date)
@@ -659,7 +673,7 @@ final class DatabaseService: Sendable {
                 .fetchAll(db)
 
             return records.compactMap { record in
-                guard let date = isoFormatter.date(from: record.timestamp) else {
+                guard let date = Self.isoDate(from: record.timestamp) else {
                     return nil
                 }
                 return (input: record.input, timestamp: date)
@@ -672,7 +686,7 @@ final class DatabaseService: Sendable {
     nonisolated func saveEmailLog(_ log: EmailLog) {
         let record = EmailLogRecord(
             id: log.id.uuidString,
-            timestamp: isoFormatter.string(from: log.timestamp),
+            timestamp: Self.isoString(from: log.timestamp),
             sender: log.sender,
             subject: log.subject,
             emailContent: log.emailContent,
@@ -698,7 +712,7 @@ final class DatabaseService: Sendable {
                 .fetchAll(db)
 
             return records.compactMap { record in
-                guard let timestamp = isoFormatter.date(from: record.timestamp),
+                guard let timestamp = Self.isoDate(from: record.timestamp),
                       let status = EmailLogStatus(rawValue: record.status),
                       let id = UUID(uuidString: record.id) else {
                     return nil
@@ -805,7 +819,7 @@ final class DatabaseService: Sendable {
     // MARK: - Embedding Operations
 
     nonisolated func saveMessageEmbedding(messageId: UUID, embedding: Data, model: String, dimension: Int) throws {
-        let now = isoFormatter.string(from: Date())
+        let now = Self.isoString(from: Date())
         let record = MessageEmbeddingRecord(
             message_id: messageId.uuidString,
             embedding: embedding,
@@ -825,7 +839,7 @@ final class DatabaseService: Sendable {
     }
 
     nonisolated func saveConversationEmbedding(conversationId: UUID, embedding: Data, model: String, dimension: Int) throws {
-        let now = isoFormatter.string(from: Date())
+        let now = Self.isoString(from: Date())
         let record = ConversationEmbeddingRecord(
             conversation_id: conversationId.uuidString,
             embedding: embedding,
@@ -881,7 +895,7 @@ final class DatabaseService: Sendable {
         return Array(results.prefix(limit))
     }
 
-    private func deserializeEmbedding(_ data: Data) -> [Float] {
+    private nonisolated func deserializeEmbedding(_ data: Data) -> [Float] {
         var embedding: [Float] = []
         embedding.reserveCapacity(data.count / 4)
 
@@ -905,7 +919,7 @@ final class DatabaseService: Sendable {
         model: String?,
         tokenCount: Int?
     ) throws {
-        let now = isoFormatter.string(from: Date())
+        let now = Self.isoString(from: Date())
         let record = ConversationSummaryRecord(
             id: UUID().uuidString,
             conversation_id: conversationId.uuidString,

oAI/Services/EmbeddingService.swift

@@ -71,7 +71,7 @@ enum EmbeddingProvider {
 // MARK: - Embedding Service
 
 final class EmbeddingService {
-    static let shared = EmbeddingService()
+    nonisolated static let shared = EmbeddingService()
 
     private let settings = SettingsService.shared
 
@@ -281,7 +281,7 @@ final class EmbeddingService {
     // MARK: - Similarity Calculation
 
     /// Calculate cosine similarity between two embeddings
-    func cosineSimilarity(_ a: [Float], _ b: [Float]) -> Float {
+    nonisolated func cosineSimilarity(_ a: [Float], _ b: [Float]) -> Float {
         guard a.count == b.count else {
             Log.api.error("Embedding dimension mismatch: \(a.count) vs \(b.count)")
             return 0.0

oAI/Services/EncryptionService.swift

@@ -29,19 +29,18 @@ import CryptoKit
 import IOKit
 
 class EncryptionService {
-    static let shared = EncryptionService()
+    nonisolated static let shared = EncryptionService()
 
-    private let salt = "oAI-secure-storage-v1" // App-specific salt
+    private let encryptionKey: SymmetricKey
-    private lazy var encryptionKey: SymmetricKey = {
-        deriveEncryptionKey()
-    }()
 
-    private init() {}
+    private init() {
+        self.encryptionKey = Self.deriveEncryptionKey()
+    }
 
     // MARK: - Public Interface
 
     /// Encrypt a string value
-    func encrypt(_ value: String) throws -> String {
+    nonisolated func encrypt(_ value: String) throws -> String {
         guard let data = value.data(using: .utf8) else {
             throw EncryptionError.invalidInput
         }
@@ -55,7 +54,7 @@ class EncryptionService {
     }
 
     /// Decrypt a string value
-    func decrypt(_ encryptedValue: String) throws -> String {
+    nonisolated func decrypt(_ encryptedValue: String) throws -> String {
         guard let data = Data(base64Encoded: encryptedValue) else {
             throw EncryptionError.invalidInput
         }
@@ -73,19 +72,17 @@ class EncryptionService {
     // MARK: - Key Derivation
 
     /// Derive encryption key from machine-specific data
-    private func deriveEncryptionKey() -> SymmetricKey {
+    private static func deriveEncryptionKey() -> SymmetricKey {
-        // Combine machine UUID + bundle ID + salt for key material
         let machineUUID = getMachineUUID()
         let bundleID = Bundle.main.bundleIdentifier ?? "com.oai.oAI"
+        let salt = "oAI-secure-storage-v1"
         let keyMaterial = "\(machineUUID)-\(bundleID)-\(salt)"
-
-        // Hash to create consistent 256-bit key
         let hash = SHA256.hash(data: Data(keyMaterial.utf8))
         return SymmetricKey(data: hash)
     }
 
     /// Get machine-specific UUID (IOPlatformUUID)
-    private func getMachineUUID() -> String {
+    private static func getMachineUUID() -> String {
         // Get IOPlatformUUID from IOKit
         let platformExpert = IOServiceGetMatchingService(
             kIOMainPortDefault,

oAI/Services/GitSyncService.swift

@@ -212,7 +212,7 @@ class GitSyncService {
 
                 // Check if conversation already exists (by ID)
                 if let existingId = UUID(uuidString: export.id) {
-                    if let existing = try? db.loadConversation(id: existingId) {
+                    if (try? db.loadConversation(id: existingId)) != nil {
                         // Already exists - skip
                         log.debug("Skipping existing conversation: \(export.name)")
                         skipped += 1

oAI/Services/SettingsService.swift

@@ -300,6 +300,24 @@ class SettingsService {
         }
     }
 
+    /// Input bar height in points — default 80
+    var inputBarHeight: Double {
+        get { cache["inputBarHeight"].flatMap(Double.init) ?? 80.0 }
+        set {
+            cache["inputBarHeight"] = String(newValue)
+            DatabaseService.shared.setSetting(key: "inputBarHeight", value: String(newValue))
+        }
+    }
+
+    /// Whether the sidebar is visible — default true
+    var sidebarVisible: Bool {
+        get { cache["sidebarVisible"] != "false" }
+        set {
+            cache["sidebarVisible"] = String(newValue)
+            DatabaseService.shared.setSetting(key: "sidebarVisible", value: String(newValue))
+        }
+    }
+
     // MARK: - MCP Permissions
 
     var mcpCanWriteFiles: Bool {

oAI/Services/UpdateCheckService.swift

@@ -35,6 +35,11 @@ final class UpdateCheckService {
 
     var updateAvailable: Bool = false
     var latestVersion: String? = nil
+    var downloadURL: URL? = nil
+
+    // Manual check state — drives the update alert in ContentView
+    var isCheckingManually: Bool = false
+    var manualCheckMessage: String? = nil
 
     private let apiURL = "https://gitlab.pm/api/v1/repos/rune/oai-swift/releases/latest"
     private let releasesURL = URL(string: "https://gitlab.pm/rune/oai-swift/releases")!
@@ -48,6 +53,24 @@ final class UpdateCheckService {
         }
     }
 
+    /// Manual check triggered from the Help menu. Non-blocking — result surfaces via manualCheckMessage.
+    func checkForUpdatesManually() {
+        guard !isCheckingManually else { return }
+        isCheckingManually = true
+        Task.detached(priority: .background) {
+            await self.performCheck()
+            let current = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String ?? ""
+            await MainActor.run {
+                if self.updateAvailable, let v = self.latestVersion {
+                    self.manualCheckMessage = String(localized: "Version \(v) is available.")
+                } else {
+                    self.manualCheckMessage = String(localized: "You're up to date (v\(current)).")
+                }
+                self.isCheckingManually = false
+            }
+        }
+    }
+
     private func performCheck() async {
         guard let url = URL(string: apiURL) else { return }
 
@@ -69,9 +92,16 @@ final class UpdateCheckService {
         let latestVer = tagName.hasPrefix("v") ? String(tagName.dropFirst()) : tagName
         let currentVer = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String ?? "0.0.0"
 
+        // Extract direct DMG download URL from release assets
+        let dmgURL: URL? = (release["assets"] as? [[String: Any]])?
+            .first { ($0["name"] as? String ?? "").lowercased().hasSuffix(".dmg") }
+            .flatMap { $0["browser_download_url"] as? String }
+            .flatMap { URL(string: $0) }
+
         if isNewer(latestVer, than: currentVer) {
             await MainActor.run {
                 self.latestVersion = latestVer
+                self.downloadURL = dmgURL
                 self.updateAvailable = true
             }
         }

oAI/Utilities/Logging.swift

@@ -52,7 +52,7 @@ enum LogLevel: Int, Comparable, CaseIterable, Sendable {
         }
     }
 
-    static func < (lhs: LogLevel, rhs: LogLevel) -> Bool {
+    nonisolated static func < (lhs: LogLevel, rhs: LogLevel) -> Bool {
         lhs.rawValue < rhs.rawValue
     }
 }
@@ -60,7 +60,7 @@ enum LogLevel: Int, Comparable, CaseIterable, Sendable {
 // MARK: - File Logger
 
 final class FileLogger: @unchecked Sendable {
-    static let shared = FileLogger()
+    nonisolated static let shared = FileLogger()
 
     private let fileHandle: FileHandle?
     private let queue = DispatchQueue(label: "com.oai.filelogger")
@@ -70,8 +70,8 @@ final class FileLogger: @unchecked Sendable {
         return f
     }()
 
-    /// Current minimum log level (read from UserDefaults for thread safety)
+    /// Current minimum log level (backed by UserDefaults — thread-safe).
-    var minimumLevel: LogLevel {
+    nonisolated var minimumLevel: LogLevel {
         get {
             let raw = UserDefaults.standard.integer(forKey: "logLevel")
             return LogLevel(rawValue: raw) ?? .info
@@ -95,7 +95,7 @@ final class FileLogger: @unchecked Sendable {
         fileHandle?.seekToEndOfFile()
     }
 
-    func write(_ level: LogLevel, category: String, message: String) {
+    nonisolated func write(_ level: LogLevel, category: String, message: String) {
         guard level >= minimumLevel else { return }
         queue.async { [weak self] in
             guard let self, let fh = self.fileHandle else { return }
@@ -114,41 +114,43 @@ final class FileLogger: @unchecked Sendable {
 
 // MARK: - App Logger (wraps os.Logger + file)
 
-struct AppLogger {
+// os.Logger methods are @MainActor in macOS 27. AppLogger is Sendable and all methods are
-    let osLogger: Logger
+// nonisolated — FileLogger runs on its own serial queue, os.Logger dispatches to main actor.
+struct AppLogger: Sendable {
+    let subsystem: String
     let category: String
 
-    func debug(_ message: String) {
+    nonisolated func debug(_ message: String) {
         FileLogger.shared.write(.debug, category: category, message: message)
-        osLogger.debug("\(message, privacy: .public)")
+        Task { @MainActor [self] in Logger(subsystem: subsystem, category: category).debug("\(message, privacy: .public)") }
     }
 
-    func info(_ message: String) {
+    nonisolated func info(_ message: String) {
         FileLogger.shared.write(.info, category: category, message: message)
-        osLogger.info("\(message, privacy: .public)")
+        Task { @MainActor [self] in Logger(subsystem: subsystem, category: category).info("\(message, privacy: .public)") }
     }
 
-    func warning(_ message: String) {
+    nonisolated func warning(_ message: String) {
         FileLogger.shared.write(.warning, category: category, message: message)
-        osLogger.warning("\(message, privacy: .public)")
+        Task { @MainActor [self] in Logger(subsystem: subsystem, category: category).warning("\(message, privacy: .public)") }
     }
 
-    func error(_ message: String) {
+    nonisolated func error(_ message: String) {
         FileLogger.shared.write(.error, category: category, message: message)
-        osLogger.error("\(message, privacy: .public)")
+        Task { @MainActor [self] in Logger(subsystem: subsystem, category: category).error("\(message, privacy: .public)") }
     }
 }
 
 // MARK: - Log Namespace
 
 enum Log {
-    private static let subsystem = "com.oai.oAI"
+    private nonisolated static let subsystem = "com.oai.oAI"
 
-    static let api      = AppLogger(osLogger: Logger(subsystem: subsystem, category: "api"), category: "api")
+    nonisolated static let api      = AppLogger(subsystem: subsystem, category: "api")
-    static let db       = AppLogger(osLogger: Logger(subsystem: subsystem, category: "database"), category: "database")
+    nonisolated static let db       = AppLogger(subsystem: subsystem, category: "database")
-    static let mcp      = AppLogger(osLogger: Logger(subsystem: subsystem, category: "mcp"), category: "mcp")
+    nonisolated static let mcp      = AppLogger(subsystem: subsystem, category: "mcp")
-    static let settings = AppLogger(osLogger: Logger(subsystem: subsystem, category: "settings"), category: "settings")
+    nonisolated static let settings = AppLogger(subsystem: subsystem, category: "settings")
-    static let search   = AppLogger(osLogger: Logger(subsystem: subsystem, category: "search"), category: "search")
+    nonisolated static let search   = AppLogger(subsystem: subsystem, category: "search")
-    static let ui       = AppLogger(osLogger: Logger(subsystem: subsystem, category: "ui"), category: "ui")
+    nonisolated static let ui       = AppLogger(subsystem: subsystem, category: "ui")
-    static let general  = AppLogger(osLogger: Logger(subsystem: subsystem, category: "general"), category: "general")
+    nonisolated static let general  = AppLogger(subsystem: subsystem, category: "general")
 }

oAI/ViewModels/ChatViewModel.swift

@@ -934,10 +934,7 @@ Don't narrate future actions ("Let me...") - just use the tools.
                             messages[index].tokens = usage.completionTokens
                             if let model = selectedModel {
                                 let hasPricing = model.pricing.prompt > 0 || model.pricing.completion > 0
-                                let cost: Double? = hasPricing
+                                let cost: Double? = hasPricing ? calculateCost(usage: usage, pricing: model.pricing) : nil
-                                    ? (Double(usage.promptTokens) * model.pricing.prompt / 1_000_000) +
-                                      (Double(usage.completionTokens) * model.pricing.completion / 1_000_000)
-                                    : nil
                                 messages[index].cost = cost
                                 sessionStats.addMessage(inputTokens: usage.promptTokens, outputTokens: usage.completionTokens, cost: cost)
                             }
@@ -1001,10 +998,7 @@ Don't narrate future actions ("Let me...") - just use the tools.
                             messages[index].tokens = usage.completionTokens
                             if let model = selectedModel {
                                 let hasPricing = model.pricing.prompt > 0 || model.pricing.completion > 0
-                                let cost: Double? = hasPricing
+                                let cost: Double? = hasPricing ? calculateCost(usage: usage, pricing: model.pricing) : nil
-                                    ? (Double(usage.promptTokens) * model.pricing.prompt / 1_000_000) +
-                                      (Double(usage.completionTokens) * model.pricing.completion / 1_000_000)
-                                    : nil
                                 messages[index].cost = cost
                                 sessionStats.addMessage(inputTokens: usage.promptTokens, outputTokens: usage.completionTokens, cost: cost)
                             }
@@ -1313,7 +1307,7 @@ Don't narrate future actions ("Let me...") - just use the tools.
                 // Append the complete system prompt (default + custom)
                 systemContent += "\n\n---\n\n" + effectiveSystemPrompt
 
-                var messagesToSend: [Message] = memoryEnabled
+                let messagesToSend: [Message] = memoryEnabled
                     ? messages.filter { $0.role != .system }
                     : [messages.last(where: { $0.role == .user })].compactMap { $0 }
 
@@ -1529,10 +1523,7 @@ Don't narrate future actions ("Let me...") - just use the tools.
                 // Calculate cost
                 if let usage = totalUsage, let model = selectedModel {
                     let hasPricing = model.pricing.prompt > 0 || model.pricing.completion > 0
-                    let cost: Double? = hasPricing
+                    let cost: Double? = hasPricing ? calculateCost(usage: usage, pricing: model.pricing) : nil
-                        ? (Double(usage.promptTokens) * model.pricing.prompt / 1_000_000) +
-                          (Double(usage.completionTokens) * model.pricing.completion / 1_000_000)
-                        : nil
                     if let index = messages.lastIndex(where: { $0.id == assistantMessage.id }) {
                         messages[index].cost = cost
                     }
@@ -1659,7 +1650,7 @@ Don't narrate future actions ("Let me...") - just use the tools.
                 if isOverloaded && attempt < maxAttempts && !Task.isCancelled {
                     let delay = Double(1 << attempt) // 2s, 4s, 8s
                     Log.api.warning("API overloaded, retrying in \(Int(delay))s (attempt \(attempt)/\(maxAttempts - 1))...")
-                    await MainActor.run {
+                    _ = await MainActor.run {
                         showSystemMessage("⏳ API overloaded, retrying in \(Int(delay))s… (attempt \(attempt)/\(maxAttempts - 1))")
                     }
                     try await Task.sleep(nanoseconds: UInt64(delay * 1_000_000_000))
@@ -2180,6 +2171,18 @@ Don't narrate future actions ("Let me...") - just use the tools.
         }
     }
 
+    /// Cost for one response's usage, accounting for Anthropic-style prompt-cache
+    /// pricing when present: cache writes cost 1.25x the base input rate, cache
+    /// reads cost 0.1x. `usage.promptTokens` is already the uncached remainder —
+    /// it does not need cache tokens subtracted from it.
+    private func calculateCost(usage: ChatResponse.Usage, pricing: ModelInfo.Pricing) -> Double {
+        let inputCost = Double(usage.promptTokens) * pricing.prompt / 1_000_000
+        let cacheReadCost = Double(usage.cacheReadInputTokens ?? 0) * pricing.prompt * 0.1 / 1_000_000
+        let cacheWriteCost = Double(usage.cacheCreationInputTokens ?? 0) * pricing.prompt * 1.25 / 1_000_000
+        let outputCost = Double(usage.completionTokens) * pricing.completion / 1_000_000
+        return inputCost + cacheReadCost + cacheWriteCost + outputCost
+    }
+
     /// Summarize a chunk of messages into a concise summary
     private func summarizeMessageChunk(_ messages: [Message]) async -> String? {
         guard let provider = providerRegistry.getProvider(for: currentProvider),

oAI/Views/Main/ChatView.swift

@@ -37,12 +37,11 @@ struct ChatView: View {
             HeaderView(
                 provider: viewModel.currentProvider,
                 model: viewModel.selectedModel,
-                stats: viewModel.sessionStats,
-                onlineMode: viewModel.onlineMode,
-                mcpEnabled: viewModel.mcpEnabled,
-                mcpStatus: viewModel.mcpStatus,
                 onModelSelect: onModelSelect,
-                onProviderChange: onProviderChange
+                onProviderChange: onProviderChange,
+                conversationName: viewModel.currentConversationName,
+                hasUnsavedChanges: viewModel.hasUnsavedChanges,
+                onQuickSave: viewModel.quickSave
             )
 
             // Messages
@@ -85,10 +84,13 @@ struct ChatView: View {
             InputBar(
                 text: $viewModel.inputText,
                 isGenerating: viewModel.isGenerating,
-                mcpStatus: viewModel.mcpStatus,
                 onlineMode: viewModel.onlineMode,
                 onSend: viewModel.sendMessage,
-                onCancel: viewModel.cancelGeneration
+                onCancel: viewModel.cancelGeneration,
+                onToggleOnline: {
+                    viewModel.onlineMode.toggle()
+                    SettingsService.shared.onlineMode = viewModel.onlineMode
+                }
             )
 
             // Footer
@@ -96,7 +98,9 @@ struct ChatView: View {
                 stats: viewModel.sessionStats,
                 conversationName: viewModel.currentConversationName,
                 hasUnsavedChanges: viewModel.hasUnsavedChanges,
-                onQuickSave: viewModel.quickSave
+                onQuickSave: viewModel.quickSave,
+                onlineMode: viewModel.onlineMode,
+                mcpEnabled: viewModel.mcpEnabled
             )
         }
         .background(Color.oaiBackground)

oAI/Views/Main/ContentView.swift

@@ -2,7 +2,7 @@
 //  ContentView.swift
 //  oAI
 //
-//  Root navigation container
+//  Root navigation container — NavigationSplitView with collapsible sidebar
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 // Copyright (C) 2026 Rune Olsen
@@ -24,30 +24,34 @@
 
 
 import SwiftUI
+#if os(macOS)
+import Darwin   // uname, sysctlbyname
+#endif
 
 struct ContentView: View {
     @Environment(ChatViewModel.self) var chatViewModel
+    private var updateService = UpdateCheckService.shared
+    @State private var columnVisibility: NavigationSplitViewVisibility = .all
+    @State private var showIntelWarning = false
 
     var body: some View {
         @Bindable var vm = chatViewModel
-        NavigationStack {
+        NavigationSplitView(columnVisibility: $columnVisibility) {
+            SidebarView()
+                .navigationSplitViewColumnWidth(min: 200, ideal: 240, max: 340)
+        } detail: {
             ChatView(
                 onModelSelect: { chatViewModel.showModelSelector = true },
                 onProviderChange: { newProvider in
                     chatViewModel.changeProvider(newProvider)
                 }
             )
-            .navigationTitle("")
-            .toolbar {
-                #if os(macOS)
-                macOSToolbar
-                #endif
-            }
         }
         .frame(minWidth: 860, minHeight: 560)
         #if os(macOS)
         .onAppear {
             NSApplication.shared.windows.forEach { $0.tabbingMode = .disallowed }
+            checkIntelWarning()
         }
         .onKeyPress(.return, phases: .down) { press in
             if press.modifiers.contains(.command) {
@@ -65,7 +69,6 @@ struct ContentView: View {
                     let oldModel = chatViewModel.selectedModel
                     chatViewModel.selectModel(model)
                     chatViewModel.showModelSelector = false
-                    // Trigger auto-save on model switch
                     Task {
                         await chatViewModel.onModelSwitch(from: oldModel, to: model)
                     }
@@ -113,125 +116,56 @@ struct ContentView: View {
                 chatViewModel.inputText = input
             })
         }
+        .alert("Intel Mac Support Ending", isPresented: $showIntelWarning) {
+            Button("Got It") {
+                UserDefaults.standard.set(true, forKey: "hasShownIntelWarning")
+            }
+        } message: {
+            Text("oAI v2.4 is the last version to support Intel Macs and Rosetta. Starting with macOS 28, oAI will require Apple Silicon. Consider upgrading your Mac to continue receiving updates.")
+        }
+        .alert("Software Update", isPresented: Binding(
+            get: { updateService.manualCheckMessage != nil },
+            set: { if !$0 { updateService.manualCheckMessage = nil } }
+        )) {
+            if updateService.updateAvailable {
+                if let url = updateService.downloadURL {
+                    Button("Download v\(updateService.latestVersion ?? "")") {
+                        NSWorkspace.shared.open(url)
+                    }
+                }
+                Button("Release Page") { updateService.openReleasesPage() }
+                Button("Later", role: .cancel) { }
+            } else {
+                Button("OK", role: .cancel) { }
+            }
+        } message: {
+            Text(updateService.manualCheckMessage ?? "")
+        }
     }
 
     #if os(macOS)
-    @ToolbarContentBuilder
+    private func checkIntelWarning() {
-    private var macOSToolbar: some ToolbarContent {
+        guard !UserDefaults.standard.bool(forKey: "hasShownIntelWarning") else { return }
-        let settings = SettingsService.shared
+        guard isIntelNative || isRosetta else { return }
-        let showLabels = settings.showToolbarLabels
+        showIntelWarning = true
-        let iconSize = settings.toolbarIconSize
-
-        ToolbarItemGroup(placement: .automatic) {
-            // New conversation
-            Button(action: { chatViewModel.newConversation() }) {
-                ToolbarLabel(title: "New Chat", systemImage: "square.and.pencil", showLabels: showLabels, iconSize: iconSize)
     }
-            .keyboardShortcut("n", modifiers: .command)
-            .help("New conversation")
 
-            Button(action: { chatViewModel.showConversations = true }) {
+    private var isIntelNative: Bool {
-                ToolbarLabel(title: "Conversations", systemImage: "clock.arrow.circlepath", showLabels: showLabels, iconSize: iconSize)
+        var systemInfo = utsname()
+        uname(&systemInfo)
+        let machine = withUnsafeBytes(of: &systemInfo.machine) {
+            String(cString: $0.bindMemory(to: CChar.self).baseAddress!)
+        }
+        return machine.contains("x86_64")
     }
-            .keyboardShortcut("l", modifiers: .command)
-            .help("Saved conversations (Cmd+L)")
 
-            Button(action: { chatViewModel.showHistory = true }) {
+    private var isRosetta: Bool {
-                ToolbarLabel(title: "History", systemImage: "list.bullet", showLabels: showLabels, iconSize: iconSize)
+        var ret: Int32 = 0
-            }
+        var size = MemoryLayout<Int32>.size
-            .keyboardShortcut("h", modifiers: .command)
+        sysctlbyname("sysctl.proc_translated", &ret, &size, nil, 0)
-            .help("Command history (Cmd+H)")
+        return ret == 1
-
-            Spacer()
-
-            Button(action: { chatViewModel.showModelSelector = true }) {
-                ToolbarLabel(title: "Model", systemImage: "cpu", showLabels: showLabels, iconSize: iconSize)
-            }
-            .keyboardShortcut("m", modifiers: .command)
-            .help("Select AI model (Cmd+M)")
-
-            Button(action: {
-                if let model = chatViewModel.selectedModel {
-                    chatViewModel.modelInfoTarget = model
-                }
-            }) {
-                ToolbarLabel(title: "Info", systemImage: "info.circle", showLabels: showLabels, iconSize: iconSize)
-            }
-            .keyboardShortcut("i", modifiers: .command)
-            .help("Model info (Cmd+I)")
-            .disabled(chatViewModel.selectedModel == nil)
-
-            Button(action: { chatViewModel.showStats = true }) {
-                ToolbarLabel(title: "Stats", systemImage: "chart.bar", showLabels: showLabels, iconSize: iconSize)
-            }
-            .help("Session statistics")
-
-            Button(action: { chatViewModel.showCredits = true }) {
-                ToolbarLabel(title: "Credits", systemImage: "creditcard", showLabels: showLabels, iconSize: iconSize)
-            }
-            .help("Check API credits")
-
-            Spacer()
-
-            Button(action: { chatViewModel.showSettings = true }) {
-                ToolbarLabel(title: "Settings", systemImage: "gearshape", showLabels: showLabels, iconSize: iconSize)
-            }
-            .keyboardShortcut(",", modifiers: .command)
-            .help("Settings (Cmd+,)")
-
-            Button(action: { chatViewModel.showHelp = true }) {
-                ToolbarLabel(title: "Help", systemImage: "questionmark.circle", showLabels: showLabels, iconSize: iconSize)
-            }
-            .keyboardShortcut("/", modifiers: .command)
-            .help("Help & commands (Cmd+/)")
-        }
     }
     #endif
-
-}
-
-// Helper view for toolbar labels
-struct ToolbarLabel: View {
-    let title: LocalizedStringKey
-    let systemImage: String
-    let showLabels: Bool
-    let iconSize: Double
-
-    // imageScale for the original range (≤32); explicit font size for the new extra-large range (>32)
-    private var scale: Image.Scale {
-        switch iconSize {
-        case ...18: return .small
-        case 19...24: return .medium
-        default: return .large
-        }
-    }
-
-    var body: some View {
-        if iconSize > 32 {
-            // Extra-large: explicit font size above the system .large ceiling
-            // Offset by 16 so slider 34→18pt, 36→20pt, 38→22pt, 40→24pt
-            if showLabels {
-                Label(title, systemImage: systemImage)
-                    .labelStyle(.titleAndIcon)
-                    .font(.system(size: iconSize - 16))
-            } else {
-                Label(title, systemImage: systemImage)
-                    .labelStyle(.iconOnly)
-                    .font(.system(size: iconSize - 16))
-            }
-        } else {
-            // Original behaviour — imageScale keeps existing look intact
-            if showLabels {
-                Label(title, systemImage: systemImage)
-                    .labelStyle(.titleAndIcon)
-                    .imageScale(scale)
-            } else {
-                Label(title, systemImage: systemImage)
-                    .labelStyle(.iconOnly)
-                    .imageScale(scale)
-            }
-        }
-    }
 }
 
 #Preview {

oAI/Views/Main/FooterView.swift

@@ -30,15 +30,22 @@ struct FooterView: View {
     let conversationName: String?
     let hasUnsavedChanges: Bool
     let onQuickSave: (() -> Void)?
+    let onlineMode: Bool
+    let mcpEnabled: Bool
+    private let settings = SettingsService.shared
 
     init(stats: SessionStats,
          conversationName: String? = nil,
          hasUnsavedChanges: Bool = false,
-         onQuickSave: (() -> Void)? = nil) {
+         onQuickSave: (() -> Void)? = nil,
+         onlineMode: Bool = false,
+         mcpEnabled: Bool = false) {
         self.stats = stats
         self.conversationName = conversationName
         self.hasUnsavedChanges = hasUnsavedChanges
         self.onQuickSave = onQuickSave
+        self.onlineMode = onlineMode
+        self.mcpEnabled = mcpEnabled
     }
 
     var body: some View {
@@ -71,26 +78,26 @@ struct FooterView: View {
 
             Spacer()
 
-            // Save indicator (only when chat has messages)
+            // Status pills — Online, MCP, Sync
-            if stats.messageCount > 0 {
+            #if os(macOS)
-                SaveIndicator(
+            HStack(spacing: 6) {
-                    conversationName: conversationName,
+                if onlineMode {
-                    hasUnsavedChanges: hasUnsavedChanges,
+                    StatusPill(icon: "globe", label: "Online", color: .green)
-                    onSave: onQuickSave
-                )
                 }
+                if mcpEnabled {
+                    StatusPill(icon: "folder", label: "MCP", color: .blue)
+                }
+                if settings.syncEnabled && settings.syncAutoSave {
+                    SyncStatusPill()
+                }
+            }
+            #endif
 
-            // Update available badge
+            // Update available badge (shows only when an update exists — no version number)
             #if os(macOS)
             UpdateBadge()
             #endif
 
-            // Shortcuts hint
-            #if os(macOS)
-            Text("⌘N New • ⌘M Model • ⌘S Save")
-                .font(.caption2)
-                .foregroundColor(.oaiSecondary)
-            #endif
         }
         .padding(.horizontal, 16)
         .padding(.vertical, 8)
@@ -242,7 +249,6 @@ struct SyncStatusFooter: View {
 
 struct UpdateBadge: View {
     private let updater = UpdateCheckService.shared
-    private let currentVersion = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String ?? "?"
 
     var body: some View {
         if updater.updateAvailable {
@@ -258,10 +264,6 @@ struct UpdateBadge: View {
             }
             .buttonStyle(.plain)
             .help("A new version is available — click to open the releases page")
-        } else {
-            Text("v\(currentVersion)")
-                .font(.caption2)
-                .foregroundColor(.oaiSecondary)
         }
     }
 }

oAI/Views/Main/HeaderView.swift

@@ -2,7 +2,8 @@
 //  HeaderView.swift
 //  oAI
 //
-//  Header bar with provider, model, and stats
+//  Slim header — provider, model name, star only.
+//  Status pills and stats live in SidebarView and FooterView respectively.
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 // Copyright (C) 2026 Rune Olsen
@@ -28,19 +29,68 @@ import SwiftUI
 struct HeaderView: View {
     let provider: Settings.Provider
     let model: ModelInfo?
-    let stats: SessionStats
-    let onlineMode: Bool
-    let mcpEnabled: Bool
-    let mcpStatus: String?
     let onModelSelect: () -> Void
     let onProviderChange: (Settings.Provider) -> Void
+    var conversationName: String? = nil
+    var hasUnsavedChanges: Bool = false
+    var onQuickSave: (() -> Void)? = nil
     private let settings = SettingsService.shared
     private let registry = ProviderRegistry.shared
-    private let gitSync = GitSyncService.shared
 
     var body: some View {
-        HStack(spacing: 20) {
+        ZStack {
-            // Provider picker dropdown — only shows configured providers
+            // Left: provider + model + star
+            HStack(spacing: 12) {
+                providerMenu
+                modelButton
+                starButton
+                Spacer()
+            }
+
+            // Center: conversation title (macOS document-title style)
+            conversationTitle
+        }
+        .padding(.horizontal, 16)
+        .padding(.vertical, 8)
+        .background(.ultraThinMaterial)
+        .overlay(
+            Rectangle()
+                .fill(Color.oaiBorder.opacity(0.5))
+                .frame(height: 1),
+            alignment: .bottom
+        )
+    }
+
+    // MARK: - Conversation title (center)
+
+    @ViewBuilder
+    private var conversationTitle: some View {
+        if let name = conversationName {
+            Button(action: { if hasUnsavedChanges { onQuickSave?() } }) {
+                HStack(spacing: 5) {
+                    if hasUnsavedChanges {
+                        Circle()
+                            .fill(Color.orange)
+                            .frame(width: 6, height: 6)
+                    }
+                    Text(name)
+                        .font(.system(size: settings.guiTextSize - 1, weight: .medium))
+                        .foregroundColor(.oaiPrimary)
+                        .lineLimit(1)
+                        .frame(maxWidth: 300)
+                }
+            }
+            .buttonStyle(.plain)
+            .disabled(!hasUnsavedChanges)
+            .help(hasUnsavedChanges ? "Unsaved changes — click to save" : "Saved")
+            .animation(.easeInOut(duration: 0.2), value: hasUnsavedChanges)
+            .animation(.easeInOut(duration: 0.2), value: name)
+        }
+    }
+
+    // MARK: - Subviews (extracted so ZStack stays readable)
+
+    private var providerMenu: some View {
         Menu {
             ForEach(registry.configuredProviders, id: \.self) { p in
                 Button {
@@ -49,9 +99,7 @@ struct HeaderView: View {
                     HStack {
                         Image(systemName: p.iconName)
                         Text(p.displayName)
-                            if p == provider {
+                        if p == provider { Image(systemName: "checkmark") }
-                                Image(systemName: "checkmark")
-                            }
                     }
                 }
             }
@@ -74,58 +122,46 @@ struct HeaderView: View {
         .menuStyle(.borderlessButton)
         .fixedSize()
         .help("Switch provider")
+    }
 
-            // Model info (clickable → model selector)
+    private var modelButton: some View {
         Button(action: onModelSelect) {
             if let model = model {
                 HStack(spacing: 6) {
                     Text(model.name)
                         .font(.system(size: settings.guiTextSize, weight: .medium))
                         .foregroundColor(.oaiPrimary)
-
-                        // Capability badges
                     HStack(spacing: 3) {
                         if model.capabilities.vision {
-                                Image(systemName: "eye")
+                            Image(systemName: "eye").font(.system(size: 9)).foregroundColor(.oaiSecondary)
-                                    .font(.system(size: 9))
-                                    .foregroundColor(.oaiSecondary)
                         }
                         if model.capabilities.tools {
-                                Image(systemName: "wrench")
+                            Image(systemName: "wrench").font(.system(size: 9)).foregroundColor(.oaiSecondary)
-                                    .font(.system(size: 9))
-                                    .foregroundColor(.oaiSecondary)
                         }
                         if model.capabilities.online {
-                                Image(systemName: "globe")
+                            Image(systemName: "globe").font(.system(size: 9)).foregroundColor(.oaiSecondary)
-                                    .font(.system(size: 9))
-                                    .foregroundColor(.oaiSecondary)
                         }
                         if model.capabilities.imageGeneration {
-                                Image(systemName: "paintbrush")
+                            Image(systemName: "paintbrush").font(.system(size: 9)).foregroundColor(.oaiSecondary)
-                                    .font(.system(size: 9))
-                                    .foregroundColor(.oaiSecondary)
                         }
                     }
-
+                    Image(systemName: "chevron.down").font(.caption2).foregroundColor(.oaiSecondary)
-                        Image(systemName: "chevron.down")
-                            .font(.caption2)
-                            .foregroundColor(.oaiSecondary)
                 }
             } else {
                 HStack(spacing: 4) {
                     Text("No model selected")
                         .font(.system(size: settings.guiTextSize))
                         .foregroundColor(.oaiSecondary)
-
+                    Image(systemName: "chevron.down").font(.caption2).foregroundColor(.oaiSecondary)
-                        Image(systemName: "chevron.down")
-                            .font(.caption2)
-                            .foregroundColor(.oaiSecondary)
                 }
             }
         }
         .buttonStyle(.plain)
         .help("Select model")
+    }
 
+    @ViewBuilder
+    private var starButton: some View {
         if let model = model {
             let isFav = settings.favoriteModelIds.contains(model.id)
             Button(action: { settings.toggleFavoriteModel(model.id) }) {
@@ -136,68 +172,10 @@ struct HeaderView: View {
             .buttonStyle(.plain)
             .help(isFav ? "Remove from favorites" : "Add to favorites")
         }
-
-            Spacer()
-
-            // Status indicators
-            HStack(spacing: 8) {
-                if model?.capabilities.imageGeneration == true {
-                    StatusPill(icon: "paintbrush", label: "Image", color: .purple)
-                }
-                if onlineMode {
-                    StatusPill(icon: "globe", label: "Online", color: .green)
-                }
-                if mcpEnabled {
-                    StatusPill(icon: "folder", label: "MCP", color: .blue)
-                }
-                if settings.syncEnabled && settings.syncAutoSave {
-                    SyncStatusPill()
-                }
-            }
-
-            // Divider between status and stats
-            if onlineMode || mcpEnabled || model?.capabilities.imageGeneration == true || (settings.syncEnabled && settings.syncAutoSave) {
-                Divider()
-                    .frame(height: 16)
-                    .opacity(0.5)
-            }
-
-            // Quick stats
-            HStack(spacing: 16) {
-                StatItem(icon: "message", value: "\(stats.messageCount)")
-                StatItem(icon: "arrow.up.arrow.down", value: stats.totalTokensDisplay)
-                StatItem(icon: "dollarsign", value: stats.totalCostDisplay)
-            }
-            .font(.caption)
-        }
-        .padding(.horizontal, 16)
-        .padding(.vertical, 10)
-        .background(.ultraThinMaterial)
-        .overlay(
-            Rectangle()
-                .fill(Color.oaiBorder.opacity(0.5))
-                .frame(height: 1),
-            alignment: .bottom
-        )
     }
 }
 
-struct StatItem: View {
+// MARK: - Status Pills (used by SidebarView)
-    let icon: String
-    let value: String
-    private let settings = SettingsService.shared
-
-    var body: some View {
-        HStack(spacing: 4) {
-            Image(systemName: icon)
-                .font(.system(size: settings.guiTextSize - 3))
-                .foregroundColor(.oaiSecondary)
-            Text(value)
-                .font(.system(size: settings.guiTextSize - 1, weight: .medium))
-                .foregroundColor(.oaiPrimary)
-        }
-    }
-}
 
 struct StatusPill: View {
     let icon: String
@@ -284,15 +262,6 @@ struct SyncStatusPill: View {
         HeaderView(
             provider: .openrouter,
             model: ModelInfo.mockModels.first,
-            stats: SessionStats(
-                totalInputTokens: 125,
-                totalOutputTokens: 434,
-                totalCost: 0.00111,
-                messageCount: 4
-            ),
-            onlineMode: true,
-            mcpEnabled: true,
-            mcpStatus: "MCP",
             onModelSelect: {},
             onProviderChange: { _ in }
         )

oAI/Views/Main/InputBar.swift

@@ -2,7 +2,7 @@
 //  InputBar.swift
 //  oAI
 //
-//  Message input bar with status indicators
+//  Message input bar with resizable height and online toggle
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 // Copyright (C) 2026 Rune Olsen
@@ -24,19 +24,30 @@
 
 
 import SwiftUI
+#if os(macOS)
+import AppKit
+#endif
 
 struct InputBar: View {
     @Binding var text: String
     let isGenerating: Bool
-    let mcpStatus: String?
     let onlineMode: Bool
     let onSend: () -> Void
     let onCancel: () -> Void
+    let onToggleOnline: () -> Void
 
     private let settings = SettingsService.shared
+
+    // Resizable input height — persisted to settings
+    @State private var inputHeight: CGFloat = CGFloat(SettingsService.shared.inputBarHeight)
+    @State private var dragStartHeight: CGFloat = CGFloat(SettingsService.shared.inputBarHeight)
+
     @State private var showCommandDropdown = false
     @State private var selectedSuggestionIndex: Int = 0
-    @FocusState private var isInputFocused: Bool
+    @State private var isInputFocused: Bool = false
+
+    private static let minInputHeight: CGFloat = 56
+    private static let maxInputHeight: CGFloat = 320
 
     /// Commands that execute immediately without additional arguments
     private static let immediateCommands: Set<String> = [
@@ -56,110 +67,98 @@ struct InputBar: View {
                     CommandSuggestionsView(
                         searchText: text,
                         selectedIndex: selectedSuggestionIndex,
-                        onSelect: { command in
+                        onSelect: selectCommand
-                            selectCommand(command)
-                        }
                     )
                     .frame(width: 400)
                     .frame(maxHeight: 200)
                     .transition(.move(edge: .bottom).combined(with: .opacity))
                     Spacer()
                 }
-                .padding(.leading, 96) // Align with input box (status badges + spacing)
+                .padding(.leading, 16)
             }
 
-            // Input area
+            // Drag-to-resize handle
+            dragHandle
+
+            // Input row
             HStack(alignment: .bottom, spacing: 12) {
-                // Status indicators
+                // Text input with globe toggle in bottom-left corner
-                HStack(spacing: 6) {
-                    if let mcp = mcpStatus {
-                        StatusBadge(text: mcp, color: .blue)
-                    }
-                    if onlineMode {
-                        StatusBadge(text: "🌐", color: .green)
-                    }
-                }
-                .frame(width: 80, alignment: .leading)
-
-                // Text input
                 ZStack(alignment: .topLeading) {
+                    // Placeholder
                     if text.isEmpty {
                         Text("Type a message or / for commands...")
                             .font(.system(size: settings.inputTextSize))
                             .foregroundColor(.oaiSecondary)
                             .padding(.horizontal, 12)
-                            .padding(.vertical, 10)
+                            .padding(.top, 10)
+                            .allowsHitTesting(false)
                     }
 
-                    TextEditor(text: $text)
+                    // Editor — fills the fixed-height box, bottom area reserved for globe
-                        .font(.system(size: settings.inputTextSize))
+                    NativeTextEditor(
-                        .foregroundColor(.oaiPrimary)
+                        text: $text,
-                        .scrollContentBackground(.hidden)
+                        font: .systemFont(ofSize: settings.inputTextSize),
-                        .frame(minHeight: 44, maxHeight: 120)
+                        textColor: NSColor(Color.oaiPrimary),
-                        .padding(.horizontal, 8)
+                        isFocused: isInputFocused,
-                        .padding(.vertical, 6)
+                        onReturn: {
-                        .focused($isInputFocused)
-                        .onChange(of: text) {
-                            showCommandDropdown = text.hasPrefix("/")
-                            selectedSuggestionIndex = 0
-                        }
-                        #if os(macOS)
-                        .onKeyPress(.upArrow) {
-                            // Navigate command dropdown
-                            if showCommandDropdown && selectedSuggestionIndex > 0 {
-                                selectedSuggestionIndex -= 1
-                                return .handled
-                            }
-                            return .ignored
-                        }
-                        .onKeyPress(.downArrow) {
-                            // Navigate command dropdown
-                            if showCommandDropdown {
-                                let count = CommandSuggestionsView.filteredCommands(for: text).count
-                                if selectedSuggestionIndex < count - 1 {
-                                    selectedSuggestionIndex += 1
-                                    return .handled
-                                }
-                            }
-                            return .ignored
-                        }
-                        .onKeyPress(.escape) {
-                            // If command dropdown is showing, close it
-                            if showCommandDropdown {
-                                showCommandDropdown = false
-                                return .handled
-                            }
-                            // If model is generating, cancel it
-                            if isGenerating {
-                                onCancel()
-                                return .handled
-                            }
-                            return .ignored
-                        }
-                        .onKeyPress(.return, phases: .down) { press in
-                            // Shift+Return: always insert newline (let system handle)
-                            if press.modifiers.contains(.shift) {
-                                return .ignored
-                            }
-
-                            // If command dropdown is showing, select the highlighted command
                             if showCommandDropdown {
                                 let suggestions = CommandSuggestionsView.filteredCommands(for: text)
                                 if !suggestions.isEmpty && selectedSuggestionIndex < suggestions.count {
                                     selectCommand(suggestions[selectedSuggestionIndex].command)
-                                    return .handled
+                                    return true
                                 }
                             }
-                            // Return (plain or with Cmd): send message
+                            if !text.isEmpty { onSend(); return true }
-                            if !text.isEmpty {
+                            return true
-                                onSend()
+                        },
-                                return .handled
+                        onEscape: {
+                            if showCommandDropdown { showCommandDropdown = false; return true }
+                            if isGenerating { onCancel(); return true }
+                            return false
+                        },
+                        onUpArrow: {
+                            if showCommandDropdown && selectedSuggestionIndex > 0 {
+                                selectedSuggestionIndex -= 1; return true
                             }
-                            // Empty text: do nothing
+                            return false
-                            return .handled
+                        },
+                        onDownArrow: {
+                            if showCommandDropdown {
+                                let count = CommandSuggestionsView.filteredCommands(for: text).count
+                                if selectedSuggestionIndex < count - 1 {
+                                    selectedSuggestionIndex += 1; return true
                                 }
-                        #endif
                             }
+                            return false
+                        },
+                        onFocusChange: { focused in isInputFocused = focused }
+                    )
+                    .frame(maxWidth: .infinity, maxHeight: .infinity)
+                    .onChange(of: text) {
+                        showCommandDropdown = text.hasPrefix("/")
+                        selectedSuggestionIndex = 0
+                    }
+                    .padding(.bottom, 30)
+
+                    // Online / offline toggle — bottom-left of the text box
+                    VStack {
+                        Spacer()
+                        HStack {
+                            Button(action: onToggleOnline) {
+                                Image(systemName: onlineMode ? "globe" : "network.slash")
+                                    .font(.system(size: 13, weight: .medium))
+                                    .foregroundStyle(onlineMode ? Color.green : Color.secondary)
+                                    .padding(8)
+                            }
+                            .buttonStyle(.plain)
+                            .help(onlineMode
+                                  ? "Online mode on — click to go offline"
+                                  : "Offline — click to go online")
+                            Spacer()
+                        }
+                    }
+                }
+                .frame(height: inputHeight)
                 .background(Color.oaiSurface)
                 .cornerRadius(8)
                 .overlay(
@@ -167,10 +166,9 @@ struct InputBar: View {
                         .stroke(isInputFocused ? Color.oaiAccent : Color.oaiBorder, lineWidth: 1)
                 )
 
-                // Action buttons
+                // Send / stop + attach buttons
                 VStack(spacing: 8) {
                     #if os(macOS)
-                    // File attach button
                     Button(action: pickFile) {
                         Image(systemName: "paperclip")
                             .font(.title2)
@@ -209,21 +207,47 @@ struct InputBar: View {
         }
     }
 
+    // MARK: - Drag handle
+
+    private var dragHandle: some View {
+        Color.clear
+            .frame(height: 8)
+            .frame(maxWidth: .infinity)
+            .contentShape(Rectangle())
+            .overlay {
+                Capsule()
+                    .fill(Color.secondary.opacity(0.25))
+                    .frame(width: 36, height: 3)
+            }
+            .gesture(
+                DragGesture(minimumDistance: 1)
+                    .onChanged { value in
+                        let proposed = dragStartHeight - value.translation.height
+                        inputHeight = max(Self.minInputHeight, min(Self.maxInputHeight, proposed))
+                    }
+                    .onEnded { _ in
+                        dragStartHeight = inputHeight
+                        settings.inputBarHeight = Double(inputHeight)
+                    }
+            )
+            #if os(macOS)
+            .onHover { hovering in
+                if hovering { NSCursor.resizeUpDown.push() } else { NSCursor.pop() }
+            }
+            #endif
+    }
+
+    // MARK: - Helpers
+
     private func selectCommand(_ command: String) {
         showCommandDropdown = false
         if Self.immediateCommands.contains(command) {
-            // Execute immediately
             text = command
             onSend()
         } else if let shortcut = SettingsService.shared.userShortcuts.first(where: { $0.command == command }) {
-            if shortcut.needsInput {
+            text = shortcut.needsInput ? command + " " : command
-                text = command + " "
+            if !shortcut.needsInput { onSend() }
         } else {
-                text = command
-                onSend()
-            }
-        } else {
-            // Put in input for user to complete
             text = command + " "
         }
     }
@@ -235,36 +259,14 @@ struct InputBar: View {
         panel.canChooseDirectories = false
         panel.canChooseFiles = true
         panel.message = "Select files to attach"
-
         guard panel.runModal() == .OK else { return }
-
+        let attachmentText = panel.urls.map { "@<\($0.path)>" }.joined(separator: " ")
-        let paths = panel.urls.map { $0.path }
+        text = text.isEmpty ? attachmentText + " " : text + " " + attachmentText
-        // Use @<path> format (angle brackets) to safely handle paths with spaces
-        let attachmentText = paths.map { "@<\($0)>" }.joined(separator: " ")
-
-        if text.isEmpty {
-            text = attachmentText + " "
-        } else {
-            text += " " + attachmentText
-        }
     }
     #endif
 }
 
-struct StatusBadge: View {
+// MARK: - Command suggestions
-    let text: String
-    let color: Color
-    
-    var body: some View {
-        Text(text)
-            .font(.caption)
-            .foregroundColor(color)
-            .padding(.horizontal, 6)
-            .padding(.vertical, 3)
-            .background(color.opacity(0.15))
-            .cornerRadius(4)
-    }
-}
 
 struct CommandSuggestionsView: View {
     let searchText: String
@@ -304,10 +306,9 @@ struct CommandSuggestionsView: View {
     ]
 
     static func allCommands() -> [(command: String, description: LocalizedStringKey)] {
-        let shortcuts = SettingsService.shared.userShortcuts.map { s in
+        SettingsService.shared.userShortcuts.map { s in
             (s.command, LocalizedStringKey("⚡ \(s.description)"))
-        }
+        } + builtInCommands
-        return builtInCommands + shortcuts
     }
 
     static func filteredCommands(for searchText: String) -> [(command: String, description: LocalizedStringKey)] {
@@ -344,26 +345,20 @@ struct CommandSuggestionsView: View {
                         .id(suggestion.command)
 
                         if index < suggestions.count - 1 {
-                            Divider()
+                            Divider().background(Color.oaiBorder)
-                                .background(Color.oaiBorder)
                         }
                     }
                 }
             }
             .onChange(of: selectedIndex) {
                 if selectedIndex < suggestions.count {
-                    withAnimation {
+                    withAnimation { proxy.scrollTo(suggestions[selectedIndex].command, anchor: .center) }
-                        proxy.scrollTo(suggestions[selectedIndex].command, anchor: .center)
-                    }
                 }
             }
         }
         .background(Color.oaiSurface)
         .cornerRadius(8)
-        .overlay(
+        .overlay(RoundedRectangle(cornerRadius: 8).stroke(Color.oaiBorder, lineWidth: 1))
-            RoundedRectangle(cornerRadius: 8)
-                .stroke(Color.oaiBorder, lineWidth: 1)
-        )
     }
 }
 
@@ -373,10 +368,10 @@ struct CommandSuggestionsView: View {
         InputBar(
             text: .constant(""),
             isGenerating: false,
-            mcpStatus: "📁 Files",
             onlineMode: true,
             onSend: {},
-            onCancel: {}
+            onCancel: {},
+            onToggleOnline: {}
         )
     }
     .background(Color.oaiBackground)

oAI/Views/Main/NativeTextEditor.swift

@@ -0,0 +1,171 @@
+//
+//  NativeTextEditor.swift
+//  oAI
+//
+//  NSViewRepresentable text editor with correct Enter-key semantics:
+//  plain Enter → send, Shift+Enter or Cmd+Enter → newline.
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+// Copyright (C) 2026 Rune Olsen
+
+import SwiftUI
+import AppKit
+
+struct NativeTextEditor: NSViewRepresentable {
+    @Binding var text: String
+    var font: NSFont
+    var textColor: NSColor
+    var isFocused: Bool
+
+    /// Plain Enter (no modifiers). Return true if the event was consumed.
+    var onReturn: () -> Bool
+    /// Escape key. Return true if consumed.
+    var onEscape: () -> Bool
+    /// Up arrow. Return true if consumed.
+    var onUpArrow: () -> Bool
+    /// Down arrow. Return true if consumed.
+    var onDownArrow: () -> Bool
+    /// Called when the view gains or loses first-responder status.
+    var onFocusChange: (Bool) -> Void
+
+    // MARK: - NSViewRepresentable
+
+    func makeNSView(context: Context) -> NSScrollView {
+        let scrollView = NSScrollView()
+        scrollView.hasVerticalScroller = false
+        scrollView.hasHorizontalScroller = false
+        scrollView.drawsBackground = false
+        scrollView.borderType = .noBorder
+
+        let tv = context.coordinator.textView
+        tv.delegate = context.coordinator
+        tv.isEditable = true
+        tv.isRichText = false
+        tv.drawsBackground = false
+        tv.backgroundColor = .clear
+        tv.isAutomaticQuoteSubstitutionEnabled = false
+        tv.isAutomaticDashSubstitutionEnabled = false
+        tv.isAutomaticSpellingCorrectionEnabled = true
+        tv.isContinuousSpellCheckingEnabled = true
+        tv.allowsUndo = true
+        tv.isVerticallyResizable = true
+        tv.isHorizontallyResizable = false
+        tv.autoresizingMask = [.width]
+        tv.textContainer?.widthTracksTextView = true
+        tv.textContainerInset = NSSize(width: 8, height: 6)
+
+        scrollView.documentView = tv
+        return scrollView
+    }
+
+    func updateNSView(_ scrollView: NSScrollView, context: Context) {
+        let tv = context.coordinator.textView
+        let coord = context.coordinator
+
+        // Update text only when it differs (avoids caret-jumping on every keystroke)
+        if tv.string != text {
+            let sel = tv.selectedRanges
+            tv.string = text
+            let len = (tv.string as NSString).length
+            tv.selectedRanges = sel.map { v in
+                let r = v.rangeValue
+                let loc = min(r.location, len)
+                let length = min(r.length, max(0, len - loc))
+                return NSValue(range: NSRange(location: loc, length: length))
+            }
+        }
+
+        if tv.font != font       { tv.font = font }
+        if tv.textColor != textColor { tv.textColor = textColor }
+
+        // Keep coordinator callbacks current with each SwiftUI render
+        coord.textBinding  = $text
+        coord.onReturn     = onReturn
+        coord.onEscape     = onEscape
+        coord.onUpArrow    = onUpArrow
+        coord.onDownArrow  = onDownArrow
+        coord.onFocusChange = onFocusChange
+
+        if isFocused {
+            DispatchQueue.main.async {
+                guard let window = tv.window, window.firstResponder !== tv else { return }
+                window.makeFirstResponder(tv)
+            }
+        }
+    }
+
+    func makeCoordinator() -> Coordinator { Coordinator() }
+
+    // MARK: - Coordinator
+
+    final class Coordinator: NSObject, NSTextViewDelegate {
+        let textView = KeyableNSTextView()
+
+        // Updated on every SwiftUI render via updateNSView
+        var textBinding:   Binding<String>?
+        var onReturn:      () -> Bool = { false }
+        var onEscape:      () -> Bool = { false }
+        var onUpArrow:     () -> Bool = { false }
+        var onDownArrow:   () -> Bool = { false }
+        var onFocusChange: (Bool) -> Void = { _ in }
+
+        override init() {
+            super.init()
+            textView.coordinator = self
+        }
+
+        func textDidChange(_ notification: Notification) {
+            guard let tv = notification.object as? NSTextView else { return }
+            textBinding?.wrappedValue = tv.string
+        }
+    }
+}
+
+// MARK: - KeyableNSTextView
+
+/// NSTextView that routes Return / Escape / arrow keys to the SwiftUI
+/// coordinator before the AppKit default handling runs.
+final class KeyableNSTextView: NSTextView {
+    weak var coordinator: NativeTextEditor.Coordinator?
+
+    override func keyDown(with event: NSEvent) {
+        guard let coord = coordinator else { super.keyDown(with: event); return }
+
+        let flags = event.modifierFlags.intersection(.deviceIndependentFlagsMask)
+        let shift = flags.contains(.shift)
+        let cmd   = flags.contains(.command)
+
+        switch event.keyCode {
+        case 36: // Return
+            if shift || cmd {
+                // Shift+Enter or Cmd+Enter → literal newline
+                insertNewlineIgnoringFieldEditor(nil)
+            } else {
+                // Plain Enter → let SwiftUI decide (send or select dropdown item)
+                if !coord.onReturn() {
+                    insertNewlineIgnoringFieldEditor(nil)
+                }
+            }
+        case 53: // Escape
+            if !coord.onEscape() { super.keyDown(with: event) }
+        case 126: // Up arrow
+            if !coord.onUpArrow() { super.keyDown(with: event) }
+        case 125: // Down arrow
+            if !coord.onDownArrow() { super.keyDown(with: event) }
+        default:
+            super.keyDown(with: event)
+        }
+    }
+
+    override func becomeFirstResponder() -> Bool {
+        let ok = super.becomeFirstResponder()
+        if ok { coordinator?.onFocusChange(true) }
+        return ok
+    }
+
+    override func resignFirstResponder() -> Bool {
+        let ok = super.resignFirstResponder()
+        if ok { coordinator?.onFocusChange(false) }
+        return ok
+    }
+}

oAI/Views/Main/SidebarView.swift

@@ -0,0 +1,216 @@
+//
+//  SidebarView.swift
+//  oAI
+//
+//  Collapsible sidebar: new chat, conversation list, status pills
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+// Copyright (C) 2026 Rune Olsen
+//
+// This file is part of oAI.
+//
+// oAI is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// oAI is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General
+// Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public
+// License along with oAI. If not, see <https://www.gnu.org/licenses/>.
+
+
+import SwiftUI
+#if os(macOS)
+import AppKit
+#endif
+
+struct SidebarView: View {
+    @Environment(ChatViewModel.self) private var chatViewModel
+    @State private var conversations: [Conversation] = []
+    @State private var searchText = ""
+
+    private var filteredConversations: [Conversation] {
+        guard !searchText.isEmpty else { return conversations }
+        return conversations.filter { $0.name.lowercased().contains(searchText.lowercased()) }
+    }
+
+    var body: some View {
+        VStack(spacing: 0) {
+            // New Chat button
+            Button(action: { chatViewModel.newConversation() }) {
+                HStack(spacing: 8) {
+                    Image(systemName: "square.and.pencil")
+                        .font(.system(size: 14))
+                    Text("New Chat")
+                        .font(.system(size: 14, weight: .medium))
+                    Spacer()
+                }
+                .foregroundColor(.oaiPrimary)
+                .padding(.horizontal, 12)
+                .padding(.vertical, 10)
+                .contentShape(Rectangle())
+            }
+            .buttonStyle(.plain)
+
+            // Search field
+            HStack(spacing: 6) {
+                Image(systemName: "magnifyingglass")
+                    .font(.system(size: 12))
+                    .foregroundStyle(.secondary)
+                TextField("Search conversations…", text: $searchText)
+                    .textFieldStyle(.plain)
+                    .font(.system(size: 13))
+                if !searchText.isEmpty {
+                    Button {
+                        searchText = ""
+                    } label: {
+                        Image(systemName: "xmark.circle.fill")
+                            .foregroundStyle(.tertiary)
+                    }
+                    .buttonStyle(.plain)
+                }
+                Divider().frame(height: 12)
+                Button {
+                    chatViewModel.showConversations = true
+                } label: {
+                    Image(systemName: "slider.horizontal.3")
+                        .font(.system(size: 11))
+                        .foregroundStyle(.secondary)
+                }
+                .buttonStyle(.plain)
+                .help("Advanced search — semantic search, bulk delete, export")
+            }
+            .padding(7)
+            .background(.quaternary.opacity(0.5), in: RoundedRectangle(cornerRadius: 6))
+            .padding(.horizontal, 8)
+            .padding(.bottom, 6)
+
+            Divider()
+
+            // Conversation list
+            if filteredConversations.isEmpty {
+                Spacer()
+                VStack(spacing: 8) {
+                    Image(systemName: searchText.isEmpty ? "tray" : "magnifyingglass")
+                        .font(.title2)
+                        .foregroundStyle(.tertiary)
+                    Text(searchText.isEmpty ? "No Saved Conversations" : "No Matches")
+                        .font(.callout)
+                        .foregroundStyle(.secondary)
+                }
+                Spacer()
+            } else {
+                List {
+                    ForEach(filteredConversations) { conversation in
+                        SidebarConversationRow(conversation: conversation)
+                            .contentShape(Rectangle())
+                            .onTapGesture {
+                                chatViewModel.loadConversation(conversation)
+                            }
+                            .listRowBackground(
+                                chatViewModel.currentConversationName == conversation.name
+                                    ? Color.oaiAccent.opacity(0.15)
+                                    : Color.clear
+                            )
+                            .swipeActions(edge: .trailing, allowsFullSwipe: false) {
+                                Button(role: .destructive) {
+                                    deleteConversation(conversation)
+                                } label: {
+                                    Label("Delete", systemImage: "trash")
+                                }
+                                Button {
+                                    renameConversation(conversation)
+                                } label: {
+                                    Label("Rename", systemImage: "pencil")
+                                }
+                                .tint(.orange)
+                            }
+                    }
+                }
+                .listStyle(.sidebar)
+            }
+
+        }
+        .onAppear { loadConversations() }
+        .onChange(of: chatViewModel.currentConversationName) { loadConversations() }
+        .onChange(of: chatViewModel.messages.count) { loadConversations() }
+    }
+
+    private func loadConversations() {
+        conversations = (try? DatabaseService.shared.listConversations()) ?? []
+    }
+
+    private func deleteConversation(_ conversation: Conversation) {
+        _ = try? DatabaseService.shared.deleteConversation(id: conversation.id)
+        withAnimation {
+            conversations.removeAll { $0.id == conversation.id }
+        }
+    }
+
+    private func renameConversation(_ conversation: Conversation) {
+        #if os(macOS)
+        let alert = NSAlert()
+        alert.messageText = "Rename Conversation"
+        alert.addButton(withTitle: "Rename")
+        alert.addButton(withTitle: "Cancel")
+        let input = NSTextField(frame: NSRect(x: 0, y: 0, width: 260, height: 24))
+        input.stringValue = conversation.name
+        input.selectText(nil)
+        alert.accessoryView = input
+        alert.window.initialFirstResponder = input
+        guard alert.runModal() == .alertFirstButtonReturn else { return }
+        let newName = input.stringValue.trimmingCharacters(in: .whitespaces)
+        guard !newName.isEmpty, newName != conversation.name else { return }
+        do {
+            _ = try DatabaseService.shared.updateConversation(id: conversation.id, name: newName, messages: nil)
+            if let i = conversations.firstIndex(where: { $0.id == conversation.id }) {
+                conversations[i].name = newName
+                conversations[i].updatedAt = Date()
+            }
+            chatViewModel.didRenameConversation(id: conversation.id, newName: newName)
+        } catch {
+            Log.db.error("Failed to rename conversation: \(error.localizedDescription)")
+        }
+        #endif
+    }
+}
+
+// MARK: - Sidebar conversation row
+
+struct SidebarConversationRow: View {
+    let conversation: Conversation
+
+    private var formattedDate: String {
+        let formatter = DateFormatter()
+        formatter.dateFormat = "dd.MM.yyyy"
+        return formatter.string(from: conversation.updatedAt)
+    }
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: 2) {
+            Text(conversation.name)
+                .font(.system(size: 13, weight: .medium))
+                .lineLimit(1)
+            HStack(spacing: 4) {
+                Text("^[\(conversation.messageCount) message](inflect: true)")
+                    .font(.system(size: 11))
+                Text("·")
+                    .font(.system(size: 11))
+                Text(formattedDate)
+                    .font(.system(size: 11))
+            }
+            .foregroundStyle(.secondary)
+        }
+        .padding(.vertical, 2)
+    }
+}
+
+#Preview {
+    SidebarView()
+        .environment(ChatViewModel())
+        .frame(width: 240, height: 600)
+}

oAI/Views/Screens/CombineConversationsSheet.swift

@@ -0,0 +1,192 @@
+//
+//  CombineConversationsSheet.swift
+//  oAI
+//
+//  Combine 2+ saved conversations into one, optionally using AI to merge content
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+// Copyright (C) 2026 Rune Olsen
+//
+// This file is part of oAI.
+//
+// oAI is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// oAI is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General
+// Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public
+// License along with oAI. If not, see <https://www.gnu.org/licenses/>.
+
+
+import SwiftUI
+
+struct CombineConversationsSheet: View {
+    @Environment(\.dismiss) var dismiss
+
+    let conversations: [Conversation]
+    var onCompleted: (Conversation) -> Void
+
+    @State private var name: String
+    @State private var mode: CombineMode = .simple
+    @State private var deleteOriginals = false
+    @State private var isProcessing = false
+    @State private var errorMessage: String?
+
+    private let settings = SettingsService.shared
+
+    init(conversations: [Conversation], onCompleted: @escaping (Conversation) -> Void) {
+        self.conversations = conversations
+        self.onCompleted = onCompleted
+        let joined = conversations.map(\.name).joined(separator: " + ")
+        _name = State(initialValue: String(joined.prefix(80)))
+    }
+
+    private var defaultModelLabel: String? {
+        guard let model = settings.defaultModel, !model.isEmpty else { return nil }
+        return "\(settings.defaultProvider.displayName) / \(model)"
+    }
+
+    private var isValid: Bool {
+        !name.trimmingCharacters(in: .whitespaces).isEmpty
+            && conversations.count >= 2
+            && (mode == .simple || defaultModelLabel != nil)
+    }
+
+    var body: some View {
+        VStack(spacing: 0) {
+            HStack {
+                Text("Combine Conversations")
+                    .font(.system(size: 18, weight: .bold))
+                Spacer()
+                Button { dismiss() } label: {
+                    Image(systemName: "xmark.circle.fill")
+                        .font(.title2).foregroundStyle(.secondary)
+                }
+                .buttonStyle(.plain)
+                .keyboardShortcut(.escape, modifiers: [])
+                .disabled(isProcessing)
+            }
+            .padding(.horizontal, 24).padding(.top, 20).padding(.bottom, 16)
+
+            Divider()
+
+            ScrollView {
+                VStack(alignment: .leading, spacing: 16) {
+                    VStack(alignment: .leading, spacing: 6) {
+                        Text("Combining \(conversations.count) conversations").font(.system(size: 13, weight: .semibold))
+                        VStack(alignment: .leading, spacing: 4) {
+                            ForEach(conversations) { conversation in
+                                Label("\(conversation.name) (\(conversation.messageCount) messages)", systemImage: "bubble.left.and.bubble.right")
+                                    .font(.system(size: 12))
+                                    .foregroundStyle(.secondary)
+                            }
+                        }
+                    }
+
+                    VStack(alignment: .leading, spacing: 6) {
+                        Text("New conversation name").font(.system(size: 13, weight: .semibold))
+                        TextField("Name", text: $name)
+                            .textFieldStyle(.roundedBorder)
+                            .disabled(isProcessing)
+                    }
+
+                    VStack(alignment: .leading, spacing: 8) {
+                        Text("Merge method").font(.system(size: 13, weight: .semibold))
+                        Picker("", selection: $mode) {
+                            Text("Simple Merge").tag(CombineMode.simple)
+                            Text("AI-Assisted Merge").tag(CombineMode.ai)
+                        }
+                        .pickerStyle(.segmented)
+                        .labelsHidden()
+                        .disabled(isProcessing)
+
+                        if mode == .simple {
+                            Text("Messages from all selected conversations are combined in chronological order.")
+                                .font(.caption).foregroundStyle(.secondary)
+                        } else {
+                            Text("A model reads all the source messages and rewrites them into one coherent, de-duplicated conversation.")
+                                .font(.caption).foregroundStyle(.secondary)
+                            if let label = defaultModelLabel {
+                                Label("Uses your default model: \(label)", systemImage: "cpu")
+                                    .font(.caption).foregroundStyle(.secondary)
+                            } else {
+                                Label("No default model configured — set one in Settings → General.", systemImage: "exclamationmark.triangle.fill")
+                                    .font(.caption).foregroundStyle(.orange)
+                            }
+                        }
+                    }
+
+                    Toggle("Delete original conversations after combining", isOn: $deleteOriginals)
+                        .toggleStyle(.checkbox)
+                        .disabled(isProcessing)
+
+                    if let errorMessage {
+                        HStack(alignment: .top, spacing: 8) {
+                            Image(systemName: "xmark.octagon.fill").foregroundStyle(.red)
+                            Text(errorMessage).font(.caption)
+                        }
+                        .padding(10)
+                        .background(.red.opacity(0.08), in: RoundedRectangle(cornerRadius: 8))
+                    }
+                }
+                .padding(.horizontal, 24).padding(.vertical, 16)
+            }
+
+            Divider()
+
+            HStack {
+                Button("Cancel") { dismiss() }
+                    .buttonStyle(.bordered)
+                    .disabled(isProcessing)
+                Spacer()
+                if isProcessing {
+                    ProgressView().controlSize(.small)
+                    Text("Combining…").font(.caption).foregroundStyle(.secondary)
+                }
+                Button("Combine") {
+                    combine()
+                }
+                .buttonStyle(.borderedProminent)
+                .disabled(!isValid || isProcessing)
+                .keyboardShortcut(.return, modifiers: [.command])
+            }
+            .padding(.horizontal, 24).padding(.vertical, 12)
+        }
+        .frame(minWidth: 520, idealWidth: 560, minHeight: 460, idealHeight: 520)
+    }
+
+    private func combine() {
+        isProcessing = true
+        errorMessage = nil
+        let ids = conversations.map(\.id)
+        let trimmedName = name.trimmingCharacters(in: .whitespaces)
+        let selectedMode = mode
+        let shouldDeleteOriginals = deleteOriginals
+
+        Task {
+            do {
+                let newConversation = try await ConversationMergeService.merge(
+                    conversationIds: ids,
+                    name: trimmedName,
+                    mode: selectedMode,
+                    deleteOriginals: shouldDeleteOriginals
+                )
+                await MainActor.run {
+                    isProcessing = false
+                    onCompleted(newConversation)
+                    dismiss()
+                }
+            } catch {
+                await MainActor.run {
+                    isProcessing = false
+                    errorMessage = error.localizedDescription
+                }
+            }
+        }
+    }
+}

oAI/Views/Screens/ConversationListView.swift

@@ -36,6 +36,7 @@ struct ConversationListView: View {
     @State private var semanticResults: [Conversation] = []
     @State private var isSearching = false
     @State private var selectedIndex: Int = 0
+    @State private var showCombineSheet = false
     @FocusState private var searchFocused: Bool
     private let settings = SettingsService.shared
     var onLoad: ((Conversation) -> Void)?
@@ -70,6 +71,18 @@ struct ConversationListView: View {
                     }
                     .buttonStyle(.plain)
 
+                    if selectedConversations.count >= 2 {
+                        Button {
+                            showCombineSheet = true
+                        } label: {
+                            HStack(spacing: 4) {
+                                Image(systemName: "arrow.triangle.merge")
+                                Text("Combine (\(selectedConversations.count))")
+                            }
+                        }
+                        .buttonStyle(.plain)
+                    }
+
                     if !selectedConversations.isEmpty {
                         Button(role: .destructive) {
                             deleteSelected()
@@ -298,6 +311,16 @@ struct ConversationListView: View {
             searchFocused = true
         }
         .frame(minWidth: 700, idealWidth: 800, minHeight: 500, idealHeight: 600)
+        .sheet(isPresented: $showCombineSheet) {
+            CombineConversationsSheet(
+                conversations: conversations.filter { selectedConversations.contains($0.id) },
+                onCompleted: { _ in
+                    loadConversations()
+                    selectedConversations.removeAll()
+                    isSelecting = false
+                }
+            )
+        }
     }
 
     private func loadConversations() {

oAI/Views/Screens/ModelInfoView.swift

@@ -30,6 +30,7 @@ struct ModelInfoView: View {
 
     @Environment(\.dismiss) var dismiss
     @Bindable private var settings = SettingsService.shared
+    @State private var isDescriptionExpanded = false
 
     var body: some View {
         VStack(spacing: 0) {
@@ -78,8 +79,18 @@ struct ModelInfoView: View {
                             Text(desc)
                                 .font(.body)
                                 .foregroundColor(.primary)
-                                .fixedSize(horizontal: false, vertical: true)
+                                .lineLimit(isDescriptionExpanded ? nil : 4)
                                 .textSelection(.enabled)
+                            if desc.count > 250 {
+                                Button(isDescriptionExpanded ? "Less" : "More…") {
+                                    withAnimation(.easeInOut(duration: 0.2)) {
+                                        isDescriptionExpanded.toggle()
+                                    }
+                                }
+                                .font(.callout)
+                                .foregroundStyle(.blue)
+                                .buttonStyle(.plain)
+                            }
                         }
                         .padding(.leading, 4)
                     }

oAI/oAIApp.swift

@@ -92,6 +92,8 @@ struct oAIApp: App {
             CommandGroup(after: .newItem) {
                 Button("Open Chat…") { chatViewModel.showConversations = true }
                     .keyboardShortcut("o", modifiers: .command)
+                Button("Search Conversations") { chatViewModel.showConversations = true }
+                    .keyboardShortcut("l", modifiers: .command)
             }
 
             CommandGroup(replacing: .saveItem) {
@@ -113,10 +115,44 @@ struct oAIApp: App {
                 .disabled(chatViewModel.messages.filter { $0.role != .system }.isEmpty)
             }
 
+            // ── View menu ─────────────────────────────────────────────────
+            CommandMenu("View") {
+                Button("Select Model") { chatViewModel.showModelSelector = true }
+                    .keyboardShortcut("m", modifiers: .command)
+
+                Button("Model Info") {
+                    chatViewModel.modelInfoTarget = chatViewModel.selectedModel
+                }
+                .keyboardShortcut("i", modifiers: .command)
+                .disabled(chatViewModel.selectedModel == nil)
+
+                Divider()
+
+                Button("Command History") { chatViewModel.showHistory = true }
+                    .keyboardShortcut("h", modifiers: .command)
+
+                Button("In-App Help") { chatViewModel.showHelp = true }
+                    .keyboardShortcut("/", modifiers: .command)
+
+                Button("Credits") { chatViewModel.showCredits = true }
+
+                Divider()
+
+                Button(chatViewModel.onlineMode ? "Online Mode: On" : "Online Mode: Off") {
+                    chatViewModel.onlineMode.toggle()
+                }
+                .keyboardShortcut("o", modifiers: [.command, .shift])
+            }
+
             // ── Help menu ─────────────────────────────────────────────────
             CommandGroup(replacing: .help) {
                 Button("oAI Help") { openHelp() }
                     .keyboardShortcut("?", modifiers: .command)
+                Divider()
+                Button(UpdateCheckService.shared.isCheckingManually ? "Checking…" : "Check for Updates…") {
+                    UpdateCheckService.shared.checkForUpdatesManually()
+                }
+                .disabled(UpdateCheckService.shared.isCheckingManually)
             }
         }
         #endif