Fix MCP disconnect handling and eager note tab swaps

crates/flynt-agent/src/main.rs

@@ -37,6 +37,21 @@ fn default_project_root() -> PathBuf {
         .join("Flynt")
 }
 
+fn is_transport_disconnect_message(msg: &str) -> bool {
+    let msg = msg.to_lowercase();
+    msg.contains("broken pipe")
+        || msg.contains("os error 32")
+        || msg.contains("connection closed")
+        || msg.contains("closed connection")
+        || msg.contains("connection reset")
+        || msg.contains("transport disconnected")
+        || msg.contains("channel closed")
+}
+
+fn is_transport_disconnect_error(err: &omegon_extension::Error) -> bool {
+    is_transport_disconnect_message(&err.to_string())
+}
+
 #[tokio::main]
 async fn main() -> Result<()> {
     tracing_subscriber::fmt()
@@ -54,8 +69,8 @@ async fn main() -> Result<()> {
         "FLYNT_PROJECT",
         &["OMEGON_PROJECT_ROOT", "FLYNT_VAULT", "CODEX_VAULT"],
     )
-        .map(PathBuf::from)
-        .unwrap_or_else(default_project_root);
+    .map(PathBuf::from)
+    .unwrap_or_else(default_project_root);
 
     std::fs::create_dir_all(&project_root)?;
     let project = Arc::new(Project::open(&project_root)?);
@@ -67,9 +82,13 @@ async fn main() -> Result<()> {
     match mode {
         Some("--mcp") => {
             // MCP server mode — compatible with Claude Code, Cursor, etc.
-            omegon_extension::mcp_shim::serve_mcp(ext)
-                .await
-                .expect("flynt MCP server failed");
+            if let Err(e) = omegon_extension::mcp_shim::serve_mcp(ext).await {
+                if is_transport_disconnect_error(&e) {
+                    tracing::warn!("flynt MCP client disconnected: {e}");
+                    return Ok(());
+                }
+                return Err(anyhow::anyhow!("flynt MCP server failed: {e}"));
+            }
         }
         Some("--help") | Some("help") | Some("-h") => {
             println!("flynt-agent — project document and task tools for omegon");
@@ -81,9 +100,15 @@ async fn main() -> Result<()> {
             println!("  flynt-agent --help         Show this help");
             println!();
             println!("ENVIRONMENT:");
-            println!("  FLYNT_PROJECT              Project directory (default: cwd if it looks like a project, otherwise ~/Documents/Flynt)");
-            println!("                             Also accepts OMEGON_PROJECT_ROOT from the native extension host.");
-            println!("                             Legacy aliases (deprecated): FLYNT_VAULT, CODEX_VAULT");
+            println!(
+                "  FLYNT_PROJECT              Project directory (default: cwd if it looks like a project, otherwise ~/Documents/Flynt)"
+            );
+            println!(
+                "                             Also accepts OMEGON_PROJECT_ROOT from the native extension host."
+            );
+            println!(
+                "                             Legacy aliases (deprecated): FLYNT_VAULT, CODEX_VAULT"
+            );
         }
         Some("--rpc") | _ => {
             // Default: run as omegon extension (v2 bidirectional protocol)
@@ -98,7 +123,7 @@ async fn main() -> Result<()> {
 
 #[cfg(test)]
 mod tests {
-    use super::looks_like_project_root;
+    use super::{is_transport_disconnect_message, looks_like_project_root};
 
     #[test]
     fn recognizes_flynt_project_root() {
@@ -119,4 +144,15 @@ mod tests {
         let tmp = tempfile::tempdir().unwrap();
         assert!(!looks_like_project_root(tmp.path()));
     }
+
+    #[test]
+    fn classifies_transport_disconnects() {
+        assert!(is_transport_disconnect_message("Broken pipe (os error 32)"));
+        assert!(is_transport_disconnect_message("connection closed"));
+        assert!(is_transport_disconnect_message(
+            "transport disconnected while writing response"
+        ));
+        assert!(!is_transport_disconnect_message("method not found"));
+        assert!(!is_transport_disconnect_message("invalid params"));
+    }
 }

crates/flynt-app/src/components/sidebar.rs

@@ -319,6 +319,9 @@ fn TreeFile(meta: DocumentMeta, depth: u32) -> Element {
             },
             style: "padding-left: {indent + 20.0}px;",
             onclick: move |_| {
+                    if let Ok(Some(doc)) = ctx.project().store.get_document(&id) {
+                        let _ = document::eval(&crate::views::notes::cm6_fast_swap_js(&doc.content));
+                    }
                     tab_state.write().open(id.clone(), title.clone());
                     // Only write route if we're not already on Notes — avoids
                     // triggering a full app route re-evaluation for no reason.
@@ -373,6 +376,9 @@ fn TreeFile(meta: DocumentMeta, depth: u32) -> Element {
                             *ctx_menu.write() = None;
                             match action.as_str() {
                                 "open-tab" => {
+                                    if let Ok(Some(doc)) = ctx.project().store.get_document(&id_for_tab) {
+                                        let _ = document::eval(&crate::views::notes::cm6_fast_swap_js(&doc.content));
+                                    }
                                     tab_state.write().open(id_for_tab.clone(), title_for_tab.clone());
                                     *active_route.write() = Route::Notes;
                                 }

crates/flynt-app/src/components/tab_bar.rs

@@ -1,14 +1,16 @@
-use dioxus::prelude::*;
-use flynt_core::store::ProjectStore;
 use crate::bootstrap::AppContext;
 use crate::state::TabState;
+use dioxus::prelude::*;
+use flynt_core::store::ProjectStore;
 
 #[component]
 pub fn TabBar() -> Element {
     let tab_state = use_context::<Signal<TabState>>();
     let tabs = tab_state.read().tabs.clone();
 
-    if tabs.is_empty() { return rsx! { div { class: "tab-bar tab-bar-empty" } }; }
+    if tabs.is_empty() {
+        return rsx! { div { class: "tab-bar tab-bar-empty" } };
+    }
 
     rsx! {
         div { class: "tab-bar",
@@ -33,7 +35,12 @@
 }
 
 #[component]
-fn TabItem(index: usize, title: String, doc_id: flynt_core::models::DocumentId, is_active: bool) -> Element {
+fn TabItem(
+    index: usize,
+    title: String,
+    doc_id: flynt_core::models::DocumentId,
+    is_active: bool,
+) -> Element {
     let ctx = use_context::<AppContext>();
     let mut tab_state = use_context::<Signal<TabState>>();
     let mut renaming = use_signal(|| false);
@@ -44,7 +51,12 @@
     rsx! {
         div {
             class: if is_active { "tab active" } else { "tab" },
-            onclick: move |_| tab_state.write().active = i,
+            onclick: move |_| {
+                if let Ok(Some(doc)) = ctx.project().store.get_document(&doc_id) {
+                    let _ = document::eval(&crate::views::notes::cm6_fast_swap_js(&doc.content));
+                }
+                tab_state.write().active = i;
+            },
             ondoubleclick: move |_| {
                 *rename_input.write() = title.clone();
                 *renaming.write() = true;

crates/flynt-app/src/views/notes.rs

@@ -314,6 +314,23 @@ fn preprocess(src: &str) -> String {
 
 // ── CM6 init JS ─────────────────────────────────────────────────────────────
 
+pub(crate) fn cm6_fast_swap_js(content: &str) -> String {
+    let escaped = serde_json::to_string(content).unwrap_or_else(|_| "\"\"".into());
+    format!(
+        r#"
+(function() {{
+    const container = document.getElementById('flynt-cm-editor');
+    const cm = window._flyntCM;
+    if (!container || !cm || !cm.dom || !container.contains(cm.dom)) return false;
+    const next = {escaped};
+    cm.dispatch({{ changes: {{ from: 0, to: cm.state.doc.length, insert: next }} }});
+    cm.scrollDOM.scrollTop = 0;
+    return true;
+}})();
+"#
+    )
+}
+
 fn cm6_init_js(content: &str) -> String {
     let escaped = serde_json::to_string(content).unwrap_or_else(|_| "\"\"".into());
     format!(