Add ChatGPT Codex sign-in flow

Examples/HermesAgentSample/HermesAgentSample/ContentView.swift

@@ -15,6 +15,7 @@ struct ContentView: View {
     @AppStorage("hermes.enableContext") private var enableContext = true
     @AppStorage("hermes.enableMemory") private var enableMemory = true
 
+    @State private var chatGPTTokens: HermesChatGPTTokenResponse?
     @State private var draft = ""
     @State private var entries: [ChatEntry] = ChatTranscriptFormatter.welcomeEntries()
     @State private var isRunning = false
@@ -76,13 +77,15 @@ struct ContentView: View {
             }
             .task {
                 loadCurrentSession()
+                loadChatGPTTokens()
             }
             .sheet(isPresented: $showingSettings) {
                 SettingsView(
                     provider: $provider,
                     baseURL: $baseURL,
                     apiKey: $apiKey,
                     model: $model,
+                    chatGPTTokens: $chatGPTTokens,
                     mlxModel: $mlxModel,
                     mlxMaxTokens: $mlxMaxTokens,
                     mlxTemperature: $mlxTemperature,
@@ -146,7 +149,14 @@ struct ContentView: View {
     }
 
     private var canSend: Bool {
-        !draft.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty && !isRunning
+        !draft.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty && !isRunning && providerIsConfigured
+    }
+
+    private var providerIsConfigured: Bool {
+        if usesChatGPTCodex {
+            return !(chatGPTTokens?.accessToken ?? "").isEmpty
+        }
+        return true
     }
 
     @ViewBuilder
@@ -247,6 +257,16 @@ struct ContentView: View {
             )
         }
 
+        if usesChatGPTCodex {
+            return .chatGPTCodex(
+                accessToken: chatGPTTokens?.accessToken ?? "",
+                model: model,
+                enableSoul: enableSoul,
+                enableContext: enableContext,
+                enableMemory: enableMemory
+            )
+        }
+
         return .openAI(
             apiKey: apiKey,
             model: model,
@@ -265,6 +285,14 @@ struct ContentView: View {
         provider == "foundation"
     }
 
+    private var usesChatGPTCodex: Bool {
+        provider == "chatgpt"
+    }
+
+    private func loadChatGPTTokens() {
+        chatGPTTokens = try? HermesChatGPTKeychainTokenStore().loadTokens()
+    }
+
     nonisolated private static func makeAgent(configuration: HermesAgentConfiguration, provider: String) throws -> HermesAgent {
         if provider == "foundation" {
             if #available(iOS 26.0, *) {

Examples/HermesAgentSample/HermesAgentSample/SettingsViews.swift

@@ -8,6 +8,7 @@ struct SettingsView: View {
     @Binding var baseURL: String
     @Binding var apiKey: String
     @Binding var model: String
+    @Binding var chatGPTTokens: HermesChatGPTTokenResponse?
     @Binding var mlxModel: String
     @Binding var mlxMaxTokens: Int
     @Binding var mlxTemperature: Double
@@ -16,6 +17,7 @@ struct SettingsView: View {
     @Binding var enableMemory: Bool
 
     @Environment(\.dismiss) private var dismiss
+    @StateObject private var chatGPTSignInState = HermesChatGPTSignInState()
 
     private var hermesHome: URL? {
         try? HermesAgent.defaultHome()
@@ -30,14 +32,47 @@ struct SettingsView: View {
             Form {
                 Section("Provider") {
                     Picker("Provider", selection: $provider) {
-                        Text("Hosted").tag("hermes")
+                        Text("API").tag("hermes")
+                        Text("ChatGPT").tag("chatgpt")
                         Text("Offline MLX").tag("mlx")
                         Text("Apple").tag("foundation")
                     }
                     .pickerStyle(.segmented)
                 }
 
-                Section("Connection") {
+                if provider == "chatgpt" {
+                    Section("ChatGPT") {
+                        if chatGPTTokens == nil {
+                            HermesChatGPTSignInButton(state: chatGPTSignInState) { tokens in
+                                chatGPTTokens = tokens
+                                baseURL = HermesChatGPTAuthConstants.codexBaseURL
+                                if model == "gpt-4.1-mini" || model.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty {
+                                    model = "gpt-5.3-codex"
+                                }
+                            }
+                        } else {
+                            Label("Signed in", systemImage: "checkmark.circle.fill")
+                                .foregroundStyle(.green)
+
+                            Button(role: .destructive) {
+                                do {
+                                    try chatGPTSignInState.signOut()
+                                    chatGPTTokens = nil
+                                } catch {
+                                    chatGPTTokens = nil
+                                }
+                            } label: {
+                                Label("Sign Out", systemImage: "rectangle.portrait.and.arrow.right")
+                            }
+                        }
+
+                        TextField("Model", text: $model)
+                            .textInputAutocapitalization(.never)
+                            .autocorrectionDisabled()
+                    }
+                }
+
+                Section("API Connection") {
                     TextField("Base URL", text: $baseURL)
                         .textInputAutocapitalization(.never)
                         .autocorrectionDisabled()

README.md

@@ -77,6 +77,30 @@ let response = try agent.send("Create hello.txt and read it back") { event in
 }
 ```
 
+To let a host app use the user's ChatGPT/Codex subscription, embed the package-provided sign-in button and keep the returned tokens in the default Keychain store:
+
+```swift
+import SwiftAgent
+import SwiftUI
+
+struct AgentSettings: View {
+    @State private var tokens: HermesChatGPTTokenResponse?
+
+    var body: some View {
+        HermesChatGPTSignInButton { signedInTokens in
+            tokens = signedInTokens
+        }
+    }
+}
+
+if let tokens {
+    let configuration = HermesAgentConfiguration.chatGPTCodex(
+        accessToken: tokens.accessToken,
+        model: "gpt-5.3-codex"
+    )
+}
+```
+
 Session management is available on the same facade:
 
 ```swift