diff --git a/Audit.md b/Audit.md
new file mode 100644
index 0000000..3a28260
--- /dev/null
+++ b/Audit.md
@@ -0,0 +1,10 @@
+# Audit Log
+
+## 2026-04-15
+
+Found and fixed 4 issues:
+
+1. **Bug: debouncedSave shared timer loses edits** (TaskDetailView.svelte) - When user edits both title and description within 400ms, only the last-edited field was saved. Fixed by always saving both fields in the debounced callback.
+2. **Code duplication: atomic_write_bytes** (google_tasks.rs) - Identical copy of `atomic_write` from storage.rs. Removed duplicate and reused the shared `pub(crate)` function.
+3. **Bug: silent success on missing workspace** (lib.rs) - Four Tauri commands (`set_webdav_config`, `set_workspace_theme`, `set_sync_interval`, `set_sync_interval_unfocused`) silently succeeded when given a nonexistent workspace ID. Fixed to return an error.
+4. **Bug: failing test due to wrong frontmatter field name** (storage.rs) - `test_parse_frontmatter_with_optional_fields` used `due:` instead of `date:` in frontmatter YAML, causing the assertion on `fm.date.is_some()` to fail.
diff --git a/apps/tauri/src-tauri/src/lib.rs b/apps/tauri/src-tauri/src/lib.rs
index ec076a5..7bdb221 100644
--- a/apps/tauri/src-tauri/src/lib.rs
+++ b/apps/tauri/src-tauri/src/lib.rs
@@ -549,9 +549,9 @@ fn set_webdav_config(
     state: State<'_, Mutex<AppState>>,
 ) -> Result<(), String> {
     let mut s = lock_state(&state)?;
-    if let Some(ws) = s.config.workspaces.get_mut(&workspace_id) {
-        ws.webdav_url = Some(webdav_url);
-    }
+    let ws = s.config.workspaces.get_mut(&workspace_id)
+        .ok_or_else(|| format!("Workspace '{}' not found", workspace_id))?;
+    ws.webdav_url = Some(webdav_url);
     s.save_config()
 }
 
@@ -562,9 +562,9 @@ fn set_workspace_theme(
     state: State<'_, Mutex<AppState>>,
 ) -> Result<(), String> {
     let mut s = lock_state(&state)?;
-    if let Some(ws) = s.config.workspaces.get_mut(&workspace_id) {
-        ws.theme = theme;
-    }
+    let ws = s.config.workspaces.get_mut(&workspace_id)
+        .ok_or_else(|| format!("Workspace '{}' not found", workspace_id))?;
+    ws.theme = theme;
     s.save_config()
 }
 
@@ -575,9 +575,9 @@ fn set_sync_interval(
     state: State<'_, Mutex<AppState>>,
 ) -> Result<(), String> {
     let mut s = lock_state(&state)?;
-    if let Some(ws) = s.config.workspaces.get_mut(&workspace_id) {
-        ws.sync_interval_secs = interval_secs;
-    }
+    let ws = s.config.workspaces.get_mut(&workspace_id)
+        .ok_or_else(|| format!("Workspace '{}' not found", workspace_id))?;
+    ws.sync_interval_secs = interval_secs;
     s.save_config()
 }
 
@@ -588,9 +588,9 @@ fn set_sync_interval_unfocused(
     state: State<'_, Mutex<AppState>>,
 ) -> Result<(), String> {
     let mut s = lock_state(&state)?;
-    if let Some(ws) = s.config.workspaces.get_mut(&workspace_id) {
-        ws.sync_interval_unfocused_secs = interval_secs;
-    }
+    let ws = s.config.workspaces.get_mut(&workspace_id)
+        .ok_or_else(|| format!("Workspace '{}' not found", workspace_id))?;
+    ws.sync_interval_unfocused_secs = interval_secs;
     s.save_config()
 }
 
diff --git a/apps/tauri/src/lib/components/TaskDetailView.svelte b/apps/tauri/src/lib/components/TaskDetailView.svelte
index b1eb8c0..e0d99fe 100644
--- a/apps/tauri/src/lib/components/TaskDetailView.svelte
+++ b/apps/tauri/src/lib/components/TaskDetailView.svelte
@@ -32,19 +32,19 @@
     if (isDesktop) appWindow.startDragging();
   }
 
-  function debouncedSave(fields: Partial<Task>) {
+  function debouncedSave() {
     clearTimeout(saveTimer);
     saveTimer = setTimeout(() => {
-      app.updateTask({ ...task, ...fields });
+      app.updateTask({ ...task, title: title.trim() || task.title, description });
     }, 400);
   }
 
   function handleTitleInput() {
-    debouncedSave({ title: title.trim() || task.title });
+    debouncedSave();
   }
 
   function handleDescInput() {
-    debouncedSave({ description });
+    debouncedSave();
   }
 
   function handleDateChange(iso: string | null, hasTime: boolean = false) {
diff --git a/crates/onyx-core/src/google_tasks.rs b/crates/onyx-core/src/google_tasks.rs
index 1f4fb34..8bf3fb1 100644
--- a/crates/onyx-core/src/google_tasks.rs
+++ b/crates/onyx-core/src/google_tasks.rs
@@ -14,7 +14,7 @@ use uuid::Uuid;
 
 use crate::error::{Error, Result};
 use crate::models::{Task, TaskStatus};
-use crate::storage::{ListMetadata, RootMetadata};
+use crate::storage::{ListMetadata, RootMetadata, atomic_write};
 
 const REQUEST_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(30);
 const CONNECT_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(10);
@@ -348,7 +348,7 @@ pub async fn sync_google_tasks(
             };
 
             let content = render_task_markdown(&task);
-            if let Err(e) = atomic_write_bytes(&task_path, content.as_bytes()) {
+            if let Err(e) = atomic_write(&task_path, content.as_bytes()) {
                 errors.push(format!("Failed to write task '{}': {}", task.title, e));
             } else {
                 downloaded += 1;
@@ -359,7 +359,7 @@ pub async fn sync_google_tasks(
         list_meta.updated_at = Utc::now();
 
         if let Ok(meta_content) = serde_json::to_string_pretty(&list_meta) {
-            let _ = atomic_write_bytes(&listdata_path, meta_content.as_bytes());
+            let _ = atomic_write(&listdata_path, meta_content.as_bytes());
         }
     }
 
@@ -375,7 +375,7 @@ pub async fn sync_google_tasks(
     };
     root_meta.list_order = new_list_order;
     if let Ok(meta_content) = serde_json::to_string_pretty(&root_meta) {
-        let _ = atomic_write_bytes(&root_meta_path, meta_content.as_bytes());
+        let _ = atomic_write(&root_meta_path, meta_content.as_bytes());
     }
 
     Ok(GoogleSyncResult { downloaded, errors })
@@ -464,13 +464,3 @@ fn sanitize_name(name: &str) -> String {
     if s.is_empty() { "Untitled".to_string() } else { s }
 }
 
-/// Write bytes to a file atomically (write to `.tmp`, then rename).
-fn atomic_write_bytes(path: &Path, content: &[u8]) -> std::io::Result<()> {
-    let temp = path.with_extension("tmp");
-    std::fs::write(&temp, content)?;
-    if let Err(e) = std::fs::rename(&temp, path) {
-        let _ = std::fs::remove_file(&temp);
-        return Err(e);
-    }
-    Ok(())
-}
diff --git a/crates/onyx-core/src/storage.rs b/crates/onyx-core/src/storage.rs
index 9796b22..42d5801 100644
--- a/crates/onyx-core/src/storage.rs
+++ b/crates/onyx-core/src/storage.rs
@@ -27,7 +27,7 @@ const DEFAULT_TASK_VERSION: u64 = 1;
 /// Write data to a temporary file then atomically rename to the target path.
 /// Prevents corruption from partial writes on crash. Cleans up temp file on
 /// rename failure to prevent accumulation.
-fn atomic_write(path: &Path, content: &[u8]) -> std::io::Result<()> {
+pub(crate) fn atomic_write(path: &Path, content: &[u8]) -> std::io::Result<()> {
     let temp = path.with_extension("tmp");
     fs::write(&temp, content)?;
     if let Err(e) = fs::rename(&temp, path) {
@@ -759,7 +759,7 @@ mod tests {
         let temp_dir = TempDir::new().unwrap();
         let storage = init_storage(&temp_dir);
 
-        let content = "---\nid: 550e8400-e29b-41d4-a716-446655440000\nstatus: backlog\ndue: 2026-06-15T12:00:00Z\nversion: 2\nparent: 660e8400-e29b-41d4-a716-446655440001\n---\n\nNotes";
+        let content = "---\nid: 550e8400-e29b-41d4-a716-446655440000\nstatus: backlog\ndate: 2026-06-15T12:00:00Z\nversion: 2\nparent: 660e8400-e29b-41d4-a716-446655440001\n---\n\nNotes";
         let (fm, _) = storage.parse_markdown_with_frontmatter(content).unwrap();
         assert!(fm.date.is_some());
         assert!(fm.parent.is_some());