diff --git a/wikiq b/wikiq
index f2cd9cd..3ed9d0e 100755
--- a/wikiq
+++ b/wikiq
@@ -37,6 +37,7 @@ import pyarrow.csv as pacsv
 
 DIFFS_URL = 'http://localhost:8000'
 
+
 class PersistMethod:
     none = 0
     sequence = 1
@@ -57,7 +58,7 @@ def fix_hex_digests(revs: list[mwxml.Revision]) -> list[mwxml.Revision]:
         if not rev.sha1 and not rev.deleted.text:
             rev.sha1 = sha1(bytes(rev.text, "utf8")).hexdigest()
         revs[i] = rev
-        i+=1
+        i += 1
     return revs
 
 
@@ -378,8 +379,7 @@ class WikiqParser:
 
         # Iterate through pages
         for page in dump:
-            incremental_diffs = []
-            previous_text = ""
+            payload = []
 
             # skip namespaces not in the filter
             if self.namespace_filter is not None:
@@ -420,33 +420,34 @@ class WikiqParser:
                     regex_matches[k].append(v)
 
                 if self.compute_incremental_diffs:
-                    payload = {
-                        'arg1': previous_text,
-                        'arg2': rev.text,
-                    }
-
-                    try:
-                        response = requests.post(DIFFS_URL, json=payload)
-                        response.raise_for_status()
-                        incremental_diffs.append(response.text)
-                    except requests.exceptions.ConnectionError as e:
-                        print(
-                            f"Connection Error: Could not connect to the server at {DIFFS_URL}. Make sure your local server is running.")
-                        print(e)
-                        raise e
-                    except requests.exceptions.HTTPError as e:
-                        print(f"HTTP Error: {e}")
-                        print(f"Response Body: {response.text}")
-                        raise e
-                    except requests.exceptions.RequestException as e:
-                        print(f"An unexpected error occurred: {e}")
-                        raise e
-
-                    previous_text = rev.text
+                    payload.append(rev.text)
 
             # Collect the set of pages currently buffered in the table so we can run multi-page functions on them.
             row_buffer = table.pop()
             if self.compute_incremental_diffs:
+                try:
+                    response = requests.post(DIFFS_URL, json=payload)
+                    response.raise_for_status()
+                    incremental_diffs = response.json()
+                except requests.exceptions.ConnectionError as e:
+                    print(
+                        f"Connection Error: Could not connect to the server at {DIFFS_URL}. Make sure your local server is running.")
+                    print(e)
+                    raise e
+                except requests.exceptions.HTTPError as e:
+                    print(f"HTTP Error: {e}")
+                    print(f"Response Body: {response.text}")
+                    raise e
+                except requests.exceptions.JSONDecodeError as e:
+                    # Must come before RequestException as JSONDecodeError is
+                    # a subclass.
+                    print(f"JSON Decode Error: {e}", file=sys.stderr)
+                    print(f"Response Body: {response.text}", file=sys.stderr)
+                    raise e
+                except requests.exceptions.RequestException as e:
+                    print(f"An unexpected error occurred: {e}")
+                    raise e
+
                 row_buffer['incremental diffs'] = incremental_diffs
 
             is_revert_column: list[Union[bool, None]] = []