diff --git a/frontend/src/api/chat.ts b/frontend/src/api/chat.ts
index cc75c36..fb0e319 100644
--- a/frontend/src/api/chat.ts
+++ b/frontend/src/api/chat.ts
@@ -42,6 +42,7 @@ export function streamChat(
   callbacks: ChatCallbacks,
   creator?: string,
   conversationId?: string,
+  personalityWeight?: number,
 ): AbortController {
   const controller = new AbortController();
 
@@ -67,6 +68,7 @@ export function streamChat(
       query,
       creator: creator ?? null,
       conversation_id: conversationId ?? null,
+      personality_weight: personalityWeight ?? 0,
     }),
     signal: controller.signal,
   })
diff --git a/frontend/src/components/ChatWidget.module.css b/frontend/src/components/ChatWidget.module.css
index 3a36018..788906f 100644
--- a/frontend/src/components/ChatWidget.module.css
+++ b/frontend/src/components/ChatWidget.module.css
@@ -67,6 +67,68 @@
   flex-shrink: 0;
 }
 
+/* ── Personality slider ───────────────────────────────────── */
+
+.sliderRow {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+  padding: 0.5rem 1rem;
+  border-bottom: 1px solid var(--color-border);
+  flex-shrink: 0;
+}
+
+.sliderLabel {
+  font-size: 0.6875rem;
+  color: var(--color-text-secondary);
+  white-space: nowrap;
+  user-select: none;
+}
+
+.slider {
+  flex: 1;
+  -webkit-appearance: none;
+  appearance: none;
+  height: 4px;
+  border-radius: 2px;
+  background: var(--color-border);
+  outline: none;
+  cursor: pointer;
+}
+
+.slider::-webkit-slider-thumb {
+  -webkit-appearance: none;
+  appearance: none;
+  width: 14px;
+  height: 14px;
+  border-radius: 50%;
+  background: var(--color-accent);
+  border: 2px solid var(--color-bg-surface);
+  box-shadow: 0 1px 4px var(--color-shadow-heavy);
+  cursor: pointer;
+  transition: transform 0.1s;
+}
+
+.slider::-webkit-slider-thumb:hover {
+  transform: scale(1.15);
+}
+
+.slider::-moz-range-thumb {
+  width: 14px;
+  height: 14px;
+  border-radius: 50%;
+  background: var(--color-accent);
+  border: 2px solid var(--color-bg-surface);
+  box-shadow: 0 1px 4px var(--color-shadow-heavy);
+  cursor: pointer;
+}
+
+.slider::-moz-range-track {
+  height: 4px;
+  border-radius: 2px;
+  background: var(--color-border);
+}
+
 .headerTitle {
   font-size: 0.875rem;
   font-weight: 600;
diff --git a/frontend/src/components/ChatWidget.tsx b/frontend/src/components/ChatWidget.tsx
index 1f45a1e..65c2fc6 100644
--- a/frontend/src/components/ChatWidget.tsx
+++ b/frontend/src/components/ChatWidget.tsx
@@ -121,6 +121,7 @@ export default function ChatWidget({ creatorName, techniques }: ChatWidgetProps)
   const [input, setInput] = useState("");
   const [streaming, setStreaming] = useState(false);
   const [conversationId, setConversationId] = useState<string | undefined>(undefined);
+  const [personalityWeight, setPersonalityWeight] = useState(0);
 
   const abortRef = useRef<AbortController | null>(null);
   const messagesEndRef = useRef<HTMLDivElement>(null);
@@ -224,9 +225,10 @@ export default function ChatWidget({ creatorName, techniques }: ChatWidgetProps)
         },
         creatorName,
         cid,
+        personalityWeight,
       );
     },
-    [messages, streaming, creatorName, conversationId],
+    [messages, streaming, creatorName, conversationId, personalityWeight],
   );
 
   const handleSubmit = (e: React.FormEvent) => {
@@ -272,6 +274,22 @@ export default function ChatWidget({ creatorName, techniques }: ChatWidgetProps)
           </button>
         </div>
 
+        {/* Personality slider */}
+        <div className={styles.sliderRow}>
+          <span className={styles.sliderLabel}>Encyclopedic</span>
+          <input
+            type="range"
+            className={styles.slider}
+            min={0}
+            max={1}
+            step={0.1}
+            value={personalityWeight}
+            onChange={(e) => setPersonalityWeight(parseFloat(e.target.value))}
+            aria-label="Personality weight"
+          />
+          <span className={styles.sliderLabel}>Creator Voice</span>
+        </div>
+
         {/* Messages */}
         <div className={styles.messages}>
           {showSuggestions && (