agent_ui: Use display name for the message editor placeholder (#45264)

Danilo Leal created 1 week ago

Follow up to a regression that happened when we introduced agent servers
that made everywhere displaying agent names use the extension name
instead of the display name. This has been since fixed in other places
and this PR now updates the agent panel's message editor, too:

| Before | After |
|--------|--------|
| <img width="1154" height="254" alt="Screenshot 2025-12-18 at 12  54
2@2x"
src="https://github.com/user-attachments/assets/5f3de9f9-4e11-42f6-90c2-56fc8cdff32e"
/> | <img width="1154" height="254" alt="Screenshot 2025-12-18 at 12 
54@2x"
src="https://github.com/user-attachments/assets/46ed5c45-7e1d-4cc6-b219-b6cc19206d1b"
/> |

Release Notes:

- N/A

Change summary

crates/agent_ui/src/acp/thread_view.rs | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)

Detailed changes

crates/agent_ui/src/acp/thread_view.rs

@@ -338,7 +338,13 @@ impl AcpThreadView {
         let prompt_capabilities = Rc::new(RefCell::new(acp::PromptCapabilities::default()));
         let available_commands = Rc::new(RefCell::new(vec![]));
 
-        let placeholder = placeholder_text(agent.name().as_ref(), false);
+        let agent_server_store = project.read(cx).agent_server_store().clone();
+        let agent_display_name = agent_server_store
+            .read(cx)
+            .agent_display_name(&ExternalAgentServerName(agent.name()))
+            .unwrap_or_else(|| agent.name());
+
+        let placeholder = placeholder_text(agent_display_name.as_ref(), false);
 
         let message_editor = cx.new(|cx| {
             let mut editor = MessageEditor::new(
@@ -377,7 +383,6 @@ impl AcpThreadView {
             )
         });
 
-        let agent_server_store = project.read(cx).agent_server_store().clone();
         let subscriptions = [
             cx.observe_global_in::<SettingsStore>(window, Self::agent_ui_font_size_changed),
             cx.observe_global_in::<AgentFontSize>(window, Self::agent_ui_font_size_changed),
@@ -1498,7 +1503,13 @@ impl AcpThreadView {
                 let has_commands = !available_commands.is_empty();
                 self.available_commands.replace(available_commands);
 
-                let new_placeholder = placeholder_text(self.agent.name().as_ref(), has_commands);
+                let agent_display_name = self
+                    .agent_server_store
+                    .read(cx)
+                    .agent_display_name(&ExternalAgentServerName(self.agent.name()))
+                    .unwrap_or_else(|| self.agent.name());
+
+                let new_placeholder = placeholder_text(agent_display_name.as_ref(), has_commands);
 
                 self.message_editor.update(cx, |editor, cx| {
                     editor.set_placeholder_text(&new_placeholder, window, cx);