diff --git a/src/feather/config.default.toml b/src/feather/config.default.toml
index 45e785b..11294a2 100644
--- a/src/feather/config.default.toml
+++ b/src/feather/config.default.toml
@@ -39,6 +39,7 @@ reader = "reader"
 # HTML template used for generating article HTML files. All templates are Jinja2 templates.
 # Available fields:
 # - id: article id (int | str)
+# - unread: if the article is unread (bool) - only makes sense if server.only_sync_unread_articles is false
 # - title: article title (str)
 # - published: article publication time (timestamp) (int)
 # - published_formatted: article publication time (text) (str)
diff --git a/src/feather/data.py b/src/feather/data.py
index abb3e99..d1d786c 100644
--- a/src/feather/data.py
+++ b/src/feather/data.py
@@ -115,7 +115,7 @@ class Article(ABC):
         article_json = { field: getattr(self, field) for field in stored_fields }
         article_json["category"] = self.category.asdict()
         if self.json_path.exists():
-            raise Exception
+            raise Exception(f"Unexpectedly tried to overwrite article data for {self.json_path}")
         with self.json_path.open("w") as f:
             json.dump(article_json, f)
     def delete_json(self):
@@ -149,6 +149,10 @@ class Article(ABC):
         self.delete() # paths might change so we preemptively remove the old file
         self.compute_fields() # recompute formatted datetime & paths from the current configuration
         self.write() # rewrite JSON & HTML
+    
+    def was_updated(self, old_article: Article):
+        """Returns true if the article is different from a previous version in a way that would require regeneration"""
+        return old_article.get_template_dict() != self.get_template_dict()
 
 class FileArticle(Article):
     def __init__(self, config: Config, json_path: Path) -> Article:
diff --git a/src/feather/feather.py b/src/feather/feather.py
index ede8949..928e45b 100755
--- a/src/feather/feather.py
+++ b/src/feather/feather.py
@@ -61,7 +61,6 @@ class FeatherApp:
             html_path = config.html_root / article.html_path
             if not html_path.exists():
                 to_mark_as_read.append(article.id)
-                article.delete()
                 marked_as_read += 1
 
         for i in range(0, len(to_mark_as_read), config.articles_per_query):
@@ -100,7 +99,7 @@ class FeatherApp:
                         new_articles += 1
                     else:
                         old_article = FileArticle(config, json_path)
-                        if article.updated > old_article.updated:
+                        if article.was_updated(old_article):
                             old_article.delete()
                             article.write()
                             updated_articles += 1