diff --git a/middleware/quota.py b/middleware/quota.py
index ba18179..0037368 100644
--- a/middleware/quota.py
+++ b/middleware/quota.py
@@ -359,11 +359,21 @@ async def finalize() -> None:
             model = usage.get("model", "unknown")
             parsed: dict | None = None
             if resp_is_text:
+                # -- Robustly extract the last JSON object -----------------
                 text_tail = streamer.get_tail().decode("utf-8", "ignore")
-                idx = max(text_tail.rfind("{"), text_tail.rfind('{"'))
-                if idx != -1:
+                # 1. Split SSE frames if present: keep only the part after the final "data: "
+                if "data:" in text_tail:
+                    *_, last_frame = text_tail.strip().split("data:")
+                    text_tail = last_frame.strip()
+                # 2. Strip the trailing '[DONE]' token if it exists
+                if text_tail.endswith("[DONE]"):
+                    text_tail = text_tail[: text_tail.rfind("[DONE]")].rstrip()
+                # 3. Find the first '{' from the *left* (because the frame has been cleaned)
+                brace = text_tail.find("{")
+                parsed = None
+                if brace != -1:
                     try:
-                        parsed = json.loads(text_tail[idx:])
+                        parsed = json.loads(text_tail[brace:])
                     except Exception:
                         parsed = None
                 if isinstance(parsed, dict):
@@ -372,9 +382,10 @@ async def finalize() -> None:
                         u = parsed.get("usage") or {}
                         tokens_out = int(u.get("completion_tokens", 0))
                         prompt_tokens = int(u.get("prompt_tokens", tokens_in))
-                        delta_prompt = prompt_tokens - tokens_in
-                        tokens_in = prompt_tokens
+                        delta_prompt = prompt_tokens - tokens_in  # adjust quota window
+                        tokens_in = prompt_tokens  # ← canonical value
                         usage["tokens_in"] = tokens_in
+                        # Replace provisional count with canonical one in the meter
                         await self.store.adjust(user, delta_prompt)
                     elif "choices" in parsed:
                         msgs = [
@@ -390,15 +401,20 @@ async def finalize() -> None:
             usage["tokens_out"] = tokens_out
             usage["model"] = model
 
+            # All *out* tokens are new – add them once.
             await self.store.adjust(user, tokens_out)
 
             total = await self.store.peek_total(user)
             if total > self.max_tokens:
                 usage["detail"] = "token quota exceeded post-stream"
 
-            response.headers["x-llm-model"] = model
-            response.headers["x-tokens-in"] = str(tokens_in)
-            response.headers["x-tokens-out"] = str(tokens_out)
+            response.headers.update(
+                {
+                    "x-llm-model": model,
+                    "x-tokens-in": str(tokens_in),
+                    "x-tokens-out": str(tokens_out),
+                }
+            )
 
             usage["ts"] = time.time()
             await request.app.state.usage.record(**usage)