feat: add dynamic window titles based on user messages

packages/opencode/src/server/server.ts

@@ -449,6 +449,36 @@ export namespace Server {
           return c.json(msg)
         },
       )
+      .post(
+        "/session_generate_title",
+        describeRoute({
+          description: "Generate a concise title for a message",
+          responses: {
+            200: {
+              description: "Generated title",
+              content: {
+                "application/json": {
+                  schema: resolver(z.object({
+                    title: z.string(),
+                  })),
+                },
+              },
+            },
+          },
+        }),
+        zValidator(
+          "json",
+          z.object({
+            text: z.string(),
+            providerID: z.string(),
+          }),
+        ),
+        async (c) => {
+          const body = c.req.valid("json")
+          const title = await Session.generateTitle(body.text, body.providerID)
+          return c.json({ title })
+        },
+      )
       .post(
         "/provider_list",
         describeRoute({

packages/opencode/src/session/index.ts

@@ -223,6 +223,64 @@ export namespace Session {
     })
   }
 
+  export async function generateTitle(userMessage: string, providerID: string): Promise<string> {
+    const log = Log.create({ service: "title-generator" })
+    const fallback = userMessage.split('\n')[0].slice(0, 40) + (userMessage.length > 40 ? '...' : '')
+    try {
+      let titleModelID: string | undefined
+      let titleProviderID: string | undefined
+      switch (providerID) {
+        case "anthropic":
+          titleModelID = "claude-3-5-haiku-20241022"
+          titleProviderID = "anthropic"
+          break
+        case "openai":
+          titleModelID = "gpt-4o-mini"
+          titleProviderID = "openai"
+          break
+        default:
+      }
+
+      if (!titleModelID || !titleProviderID) {
+        return fallback
+      }
+
+      try {
+        await Provider.getModel(titleProviderID, titleModelID)
+      } catch {
+        return fallback
+      }
+
+      const model = await Provider.getModel(titleProviderID, titleModelID)
+
+      const result = await generateText({
+        model: model.language,
+        messages: [
+          {
+            role: "system",
+            content: SystemPrompt.windowTitle()
+          },
+          {
+            role: "user",
+            content: userMessage
+          }],
+        maxTokens: 20,
+        temperature: 0,
+      })
+
+      const title = result.text?.trim() || fallback
+
+      // Ensure title is not too long
+      if (title.length > 40) {
+        return title.slice(0, 37) + '...'
+      }
+
+      return title
+    } catch (error) {
+      log.error("Failed to generate title", { error })
+      return fallback
+    }
+  }
   export async function chat(input: {
     sessionID: string
     providerID: string

packages/opencode/src/session/prompt/title-window.txt

@@ -0,0 +1 @@
+Summarize this coding conversation and generate a concise title (under 50 characters) for this message. Focus on the main action or intent. nCapture the main task, key files, problems addressed, and current status. Use active verbs when possible. Omit articles and unnecessary words. Output only the title, nothing else.

packages/opencode/src/session/system.ts

@@ -9,6 +9,7 @@ import PROMPT_ANTHROPIC from "./prompt/anthropic.txt"
 import PROMPT_ANTHROPIC_SPOOF from "./prompt/anthropic_spoof.txt"
 import PROMPT_SUMMARIZE from "./prompt/summarize.txt"
 import PROMPT_TITLE from "./prompt/title.txt"
+import PROMPT_TITLE_WINDOW from "./prompt/title-window.txt"
 
 export namespace SystemPrompt {
   export function provider(providerID: string) {
@@ -134,4 +135,8 @@ export namespace SystemPrompt {
         return [PROMPT_TITLE]
     }
   }
+
+  export function windowTitle() {
+    return PROMPT_TITLE_WINDOW
+  }
 }

packages/tui/internal/app/app.go

@@ -44,6 +44,9 @@ type SendMsg struct {
 	Text        string
 	Attachments []Attachment
 }
+type WindowTitleMsg struct {
+	Title string
+}
 type CompletionDialogTriggerdMsg struct {
 	InitialValue string
 }
@@ -389,6 +392,28 @@ func (a *App) ListProviders(ctx context.Context) ([]client.ProviderInfo, error)
 	return providers.Providers, nil
 }
 
+func (a *App) GenerateWindowTitle(ctx context.Context, text string) (string, error) {
+	if a.Provider == nil {
+		return "", fmt.Errorf("no provider configured")
+	}
+
+	requestBody := client.PostSessionGenerateTitleJSONRequestBody{
+		Text:       text,
+		ProviderID: a.Provider.Id,
+	}
+
+	response, err := a.Client.PostSessionGenerateTitleWithResponse(ctx, requestBody)
+	if err != nil {
+		return "", err
+	}
+
+	if response.StatusCode() != 200 || response.JSON200 == nil {
+		return "", fmt.Errorf("failed to generate title: status %d", response.StatusCode())
+	}
+
+	return response.JSON200.Title, nil
+}
+
 // func (a *App) loadCustomKeybinds() {
 //
 // }

packages/tui/internal/tui/tui.go

@@ -40,6 +40,26 @@ type appModel struct {
 	leaderBinding        *key.Binding
 	isLeaderSequence     bool
 	toastManager         *toast.ToastManager
+	lastSubmittedMessage string
+	wasProcessing        bool
+}
+
+func formatWindowTitle(message string) string {
+	if message == "" {
+		return "opencode"
+	}
+
+	// Take first line only
+	lines := strings.Split(message, "\n")
+	title := strings.TrimSpace(lines[0])
+
+	// Truncate if too long
+	maxLen := 50
+	if len(title) > maxLen {
+		title = title[:maxLen-3] + "..."
+	}
+
+	return "opencode: " + title
 }
 
 func (a appModel) Init() tea.Cmd {
@@ -56,6 +76,9 @@ func (a appModel) Init() tea.Cmd {
 	cmds = append(cmds, a.completions.Init())
 	cmds = append(cmds, a.toastManager.Init())
 
+	// Set initial window title
+	cmds = append(cmds, tea.SetWindowTitle("opencode"))
+
 	// Check if we should show the init dialog
 	cmds = append(cmds, func() tea.Msg {
 		shouldShow := a.app.Info.Git && a.app.Info.Time.Initialized == nil
@@ -208,8 +231,23 @@ func (a appModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 	case app.SendMsg:
 		a.showCompletionDialog = false
+		a.lastSubmittedMessage = msg.Text
 		cmd := a.app.SendChatMessage(context.Background(), msg.Text, msg.Attachments)
 		cmds = append(cmds, cmd)
+
+		// Generate title asynchronously
+		cmds = append(cmds, func() tea.Msg {
+			title, err := a.app.GenerateWindowTitle(context.Background(), msg.Text)
+			if err != nil {
+				slog.Debug("Failed to generate window title", "error", err)
+				// Fall back to truncated message
+				title = formatWindowTitle(msg.Text)
+			} else {
+				// Prepend "opencode: " to AI-generated title
+				title = "opencode: " + title
+			}
+			return app.WindowTitleMsg{Title: title}
+		})
 	case dialog.CompletionDialogCloseMsg:
 		a.showCompletionDialog = false
 	case client.EventInstallationUpdated:
@@ -261,6 +299,10 @@ func (a appModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 		a.app.Session = msg
 		a.app.Messages = messages
+		a.lastSubmittedMessage = ""
+		cmds = append(cmds, tea.SetWindowTitle("opencode"))
+	case app.WindowTitleMsg:
+		return a, tea.SetWindowTitle(msg.Title)
 	case app.ModelSelectedMsg:
 		a.app.Provider = &msg.Provider
 		a.app.Model = &msg.Model
@@ -308,6 +350,14 @@ func (a appModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		cmds = append(cmds, cmd)
 	}
 
+	// Check if AI finished processing and reset title
+	isProcessing := a.app.IsBusy()
+	if a.wasProcessing && !isProcessing && a.lastSubmittedMessage != "" {
+		a.lastSubmittedMessage = ""
+		cmds = append(cmds, tea.SetWindowTitle("opencode"))
+	}
+	a.wasProcessing = isProcessing
+
 	return a, tea.Batch(cmds...)
 }
 
@@ -415,7 +465,9 @@ func (a appModel) executeCommand(command commands.Command) (tea.Model, tea.Cmd)
 		}
 		a.app.Session = &client.SessionInfo{}
 		a.app.Messages = []client.MessageInfo{}
+		a.lastSubmittedMessage = ""
 		cmds = append(cmds, util.CmdHandler(app.SessionClearedMsg{}))
+		cmds = append(cmds, tea.SetWindowTitle("opencode"))
 	case commands.SessionListCommand:
 		sessionDialog := dialog.NewSessionDialog(a.app)
 		a.modal = sessionDialog
@@ -443,7 +495,8 @@ func (a appModel) executeCommand(command commands.Command) (tea.Model, tea.Cmd)
 			return a, nil
 		}
 		a.app.Cancel(context.Background(), a.app.Session.Id)
-		return a, nil
+		a.lastSubmittedMessage = ""
+		return a, tea.SetWindowTitle("opencode")
 	case commands.SessionCompactCommand:
 		if a.app.Session.Id == "" {
 			return a, nil