diff --git a/kate/ollie_ghost.cpp b/kate/ollie_ghost.cpp
index 128c62f..8c0ab56 100644
--- a/kate/ollie_ghost.cpp
+++ b/kate/ollie_ghost.cpp
@@ -371,6 +371,11 @@ void OllieGhostProvider::requestCompletion()
     process->closeWriteChannel();
 }
 
+// === Completion post-processing helpers (mirrors agent/complete.go) ===
+
+static QString stripCompletionNoise(const QString &s);
+static QString stripPrefixEcho(const QString &result, const QString &prefix = QString());
+
 void OllieGhostProvider::onCompletionReply(const QString &result)
 {
     if (result.trimmed().isEmpty())
@@ -530,8 +535,10 @@ static QString stripCompletionNoise(const QString &s)
     return filtered.join('\n');
 }
 
-static QString stripPrefixEcho(const QString &prefix, const QString &result)
+static QString stripPrefixEcho(const QString &result, const QString &prefix)
 {
+    if (prefix.isEmpty())
+        return result;
     int tailMax = 200;
     if (prefix.size() < tailMax)
         tailMax = prefix.size();