diff --git a/backend/routes.py b/backend/routes.py
index 7dbd646..3b9daad 100644
--- a/backend/routes.py
+++ b/backend/routes.py
@@ -6,18 +6,25 @@
 from app.core.events.enums import EventType, PlatformType
 from app.core.events.base import BaseEvent
 from app.core.handler.handler_registry import HandlerRegistry
-from pydantic import BaseModel
+from pydantic import BaseModel, ValidationError
+from typing import Optional, Dict, Any
 
 router = APIRouter()
 
 class RepoRequest(BaseModel):
     repo_url: str
 
+class GitHubWebhookPayload(BaseModel):
+    action: Optional[str] = None
+    sender: Optional[Dict[str, Any]] = None
+    pull_request: Optional[Dict[str, Any]] = None
+
 
 logging.basicConfig(level=logging.INFO)
 handler_registry = HandlerRegistry()
 event_bus = EventBus(handler_registry)
 
+
 # Sample handler function to process events
 async def sample_handler(event: BaseEvent):
     logging.info(f"Handler received event: {event.event_type} with data: {event.raw_data}")
@@ -35,9 +42,22 @@ def register_event_handlers():
     event_bus.register_handler(EventType.PR_COMMENTED, sample_handler, PlatformType.GITHUB)
     event_bus.register_handler(EventType.PR_MERGED, sample_handler, PlatformType.GITHUB)
 
+register_event_handlers()
+
 @router.post("/github/webhook")
 async def github_webhook(request: Request):
-    payload = await request.json()
+    try:
+        raw_payload = await request.json()
+    except Exception as e:
+        logging.error("Failed to parse JSON payload")
+        raise HTTPException(status_code=400, detail="Invalid JSON payload") from e
+
+    try:
+        payload = GitHubWebhookPayload(**raw_payload)
+    except ValidationError as e:
+        logging.error(f"Webhook schema validation failed: {e}")
+        raise HTTPException(status_code=422, detail="Invalid webhook schema") from e
+
     event_header = request.headers.get("X-GitHub-Event")
     logging.info(f"Received GitHub event: {event_header}")
 
@@ -45,7 +65,7 @@ async def github_webhook(request: Request):
 
     # Handle issue events
     if event_header == "issues":
-        action = payload.get("action")
+        action = payload.action
         if action == "opened":
             event_type = EventType.ISSUE_CREATED
         elif action == "closed":
@@ -55,27 +75,27 @@ async def github_webhook(request: Request):
 
     # Handle issue comment events
     elif event_header == "issue_comment":
-        action = payload.get("action")
+        action = payload.action
         if action == "created":
             event_type = EventType.ISSUE_COMMENTED
 
     # Handle pull request events
     elif event_header == "pull_request":
-        action = payload.get("action")
+        action = payload.action
         if action == "opened":
             event_type = EventType.PR_CREATED
         elif action == "edited":
             event_type = EventType.PR_UPDATED
         elif action == "closed":
             # Determine if the PR was merged or simply closed
-            if payload.get("pull_request", {}).get("merged"):
+            if payload.pull_request and payload.pull_request.get("merged"):
                 event_type = EventType.PR_MERGED
             else:
                 logging.info("Pull request closed without merge; no event dispatched.")
 
     # Handle pull request comment events
-    elif event_header in ["pull_request_review_comment", "pull_request_comment"]:
-        action = payload.get("action")
+    elif event_header in ["pull_request_review_comment", "pull_request_review"]:
+        action = payload.action
         if action == "created":
             event_type = EventType.PR_COMMENTED
 
@@ -83,13 +103,13 @@ async def github_webhook(request: Request):
     if event_type:
         event = BaseEvent(
             id=str(uuid.uuid4()),
-            actor_id=str(payload.get("sender", {}).get("id", "unknown")),
+            actor_id=str(payload.sender.get("id", "unknown")) if payload.sender else "unknown",
             event_type=event_type,
             platform=PlatformType.GITHUB,
-            raw_data=payload
+            raw_data=raw_payload
         )
         await event_bus.dispatch(event)
     else:
-        logging.info(f"No matching event type for header: {event_header} with action: {payload.get('action')}")
+        logging.warning(f"No matching event type for header: {event_header} with action: {payload.action}")
 
     return {"status": "ok"}