diff --git a/aider/coders/editblock_coder.py b/aider/coders/editblock_coder.py
index 622b17043..5388bbac7 100644
--- a/aider/coders/editblock_coder.py
+++ b/aider/coders/editblock_coder.py
@@ -348,12 +348,14 @@ def find_original_update_blocks(content):
                     if current_filename:
                         filename = current_filename
                     else:
-                        raise ValueError(f"Bad/missing filename. It should go right above {HEAD}")
+                        raise ValueError(
+                            f"Bad/missing filename. It should go right above the {HEAD}"
+                        )
             except IndexError:
                 if current_filename:
                     filename = current_filename
                 else:
-                    raise ValueError(f"Bad/missing filename. It should go right above {HEAD}")
+                    raise ValueError(f"Bad/missing filename. It should go right above the {HEAD}")
 
             current_filename = filename
 
diff --git a/aider/coders/editblock_prompts.py b/aider/coders/editblock_prompts.py
index 3874cf232..117503a41 100644
--- a/aider/coders/editblock_prompts.py
+++ b/aider/coders/editblock_prompts.py
@@ -32,22 +32,22 @@ some/dir/example.py
 >>>>>>> updated
 {fence[1]}
 
-A program will parse the edit blocks you generate and replace the HEAD lines with the `updated` lines.
+A program will parse the edit blocks you generate and replace the `HEAD` lines with the `updated` lines.
 So edit blocks must be precise and unambiguous!
 
 Every *edit block* must be fenced with {fence[0]}...{fence[1]} with the correct code language.
 Every *edit block* must start with the full path! *NEVER* propose edit blocks for *read-only* files.
 
-The HEAD section must be an *exact set of sequential lines* from the file!
-NEVER SKIP LINES in the HEAD section!
+The `HEAD` section must be an *exact set of sequential lines* from the file!
+NEVER SKIP LINES in the `HEAD` section!
 NEVER ELIDE LINES AND REPLACE THEM WITH A COMMENT!
-NEVER OMIT ANY WHITESPACE in the HEAD section!
+NEVER OMIT ANY WHITESPACE in the `HEAD` section!
 
 Edits to different parts of a file each need their own *edit block*.
 
 If you want to put code in a new file, use an edit block with:
 - A new file path, including dir name if needed
-- An empty HEAD section
+- An empty `HEAD` section
 - The new file's contents in the `updated` section
 """