Revert "Add reminder message about system prompt" (#28482)

This breaks the agentic loop.

assets/prompts/assistant_system_prompt_reminder.hbs

@@ -1 +0,0 @@
-In your response, make sure to remember and follow my instructions about how to format code blocks (and don't mention that you are remembering it, just follow the instructions).

crates/agent/src/thread.rs

@@ -1000,20 +1000,6 @@ impl Thread {
 
         self.attached_tracked_files_state(&mut request.messages, cx);
 
-        // Add reminder to the last user message about code blocks
-        if let Some(last_user_message) = request
-            .messages
-            .iter_mut()
-            .rev()
-            .find(|msg| msg.role == Role::User)
-        {
-            last_user_message
-                .content
-                .push(MessageContent::Text(system_prompt_reminder(
-                    &self.prompt_builder,
-                )));
-        }
-
         request
     }
 
@@ -1889,12 +1875,6 @@ impl Thread {
     }
 }
 
-pub fn system_prompt_reminder(prompt_builder: &prompt_store::PromptBuilder) -> String {
-    prompt_builder
-        .generate_assistant_system_prompt_reminder()
-        .unwrap_or_default()
-}
-
 #[derive(Debug, Clone)]
 pub enum ThreadError {
     PaymentRequired,
@@ -1964,7 +1944,7 @@ mod tests {
         )
         .await;
 
-        let (_workspace, _thread_store, thread, context_store, prompt_builder) =
+        let (_workspace, _thread_store, thread, context_store) =
             setup_test_environment(cx, project.clone()).await;
 
         add_file_to_context(&project, &context_store, "test/code.rs", cx)
@@ -2018,14 +1998,8 @@ fn main() {{
         });
 
         assert_eq!(request.messages.len(), 1);
-        let actual_message = request.messages[0].string_contents();
-        let expected_content = format!(
-            "{}Please explain this code{}",
-            expected_context,
-            system_prompt_reminder(&prompt_builder)
-        );
-
-        assert_eq!(actual_message, expected_content);
+        let expected_full_message = format!("{}Please explain this code", expected_context);
+        assert_eq!(request.messages[0].string_contents(), expected_full_message);
     }
 
     #[gpui::test]
@@ -2042,7 +2016,7 @@ fn main() {{
         )
         .await;
 
-        let (_, _thread_store, thread, context_store, _prompt_builder) =
+        let (_, _thread_store, thread, context_store) =
             setup_test_environment(cx, project.clone()).await;
 
         // Open files individually
@@ -2142,7 +2116,7 @@ fn main() {{
         )
         .await;
 
-        let (_, _thread_store, thread, _context_store, prompt_builder) =
+        let (_, _thread_store, thread, _context_store) =
             setup_test_environment(cx, project.clone()).await;
 
         // Insert user message without any context (empty context vector)
@@ -2168,14 +2142,11 @@ fn main() {{
         });
 
         assert_eq!(request.messages.len(), 1);
-        let actual_message = request.messages[0].string_contents();
-        let expected_content = format!(
-            "What is the best way to learn Rust?{}",
-            system_prompt_reminder(&prompt_builder)
+        assert_eq!(
+            request.messages[0].string_contents(),
+            "What is the best way to learn Rust?"
         );
 
-        assert_eq!(actual_message, expected_content);
-
         // Add second message, also without context
         let message2_id = thread.update(cx, |thread, cx| {
             thread.insert_user_message("Are there any good books?", vec![], None, cx)
@@ -2191,17 +2162,14 @@ fn main() {{
         });
 
         assert_eq!(request.messages.len(), 2);
-        // First message should be the system prompt
-        assert_eq!(request.messages[0].role, Role::User);
-
-        // Second message should be the user message with prompt reminder
-        let actual_message = request.messages[1].string_contents();
-        let expected_content = format!(
-            "Are there any good books?{}",
-            system_prompt_reminder(&prompt_builder)
+        assert_eq!(
+            request.messages[0].string_contents(),
+            "What is the best way to learn Rust?"
+        );
+        assert_eq!(
+            request.messages[1].string_contents(),
+            "Are there any good books?"
         );
-
-        assert_eq!(actual_message, expected_content);
     }
 
     #[gpui::test]
@@ -2214,7 +2182,7 @@ fn main() {{
         )
         .await;
 
-        let (_workspace, _thread_store, thread, context_store, prompt_builder) =
+        let (_workspace, _thread_store, thread, context_store) =
             setup_test_environment(cx, project.clone()).await;
 
         // Open buffer and add it to context
@@ -2274,14 +2242,11 @@ fn main() {{
         // The last message should be the stale buffer notification
         assert_eq!(last_message.role, Role::User);
 
-        let actual_message = last_message.string_contents();
-        let expected_content = format!(
-            "These files changed since last read:\n- code.rs\n{}",
-            system_prompt_reminder(&prompt_builder)
-        );
-
+        // Check the exact content of the message
+        let expected_content = "These files changed since last read:\n- code.rs\n";
         assert_eq!(
-            actual_message, expected_content,
+            last_message.string_contents(),
+            expected_content,
             "Last message should be exactly the stale buffer notification"
         );
     }
@@ -2319,27 +2284,24 @@ fn main() {{
         Entity<ThreadStore>,
         Entity<Thread>,
         Entity<ContextStore>,
-        Arc<PromptBuilder>,
     ) {
         let (workspace, cx) =
             cx.add_window_view(|window, cx| Workspace::test_new(project.clone(), window, cx));
 
-        let prompt_builder = Arc::new(PromptBuilder::new(None).unwrap());
-
         let thread_store = cx.update(|_, cx| {
-            ThreadStore::new(project.clone(), Arc::default(), prompt_builder.clone(), cx).unwrap()
+            ThreadStore::new(
+                project.clone(),
+                Arc::default(),
+                Arc::new(PromptBuilder::new(None).unwrap()),
+                cx,
+            )
+            .unwrap()
         });
 
         let thread = thread_store.update(cx, |store, cx| store.create_thread(cx));
         let context_store = cx.new(|_cx| ContextStore::new(project.downgrade(), None));
 
-        (
-            workspace,
-            thread_store,
-            thread,
-            context_store,
-            prompt_builder,
-        )
+        (workspace, thread_store, thread, context_store)
     }
 
     async fn add_file_to_context(

crates/prompt_store/src/prompts.rs

@@ -261,12 +261,6 @@ impl PromptBuilder {
             .render("assistant_system_prompt", context)
     }
 
-    pub fn generate_assistant_system_prompt_reminder(&self) -> Result<String, RenderError> {
-        self.handlebars
-            .lock()
-            .render("assistant_system_prompt_reminder", &())
-    }
-
     pub fn generate_inline_transformation_prompt(
         &self,
         user_prompt: String,