bugs & error fix 🗿

graph.py

@@ -15,7 +15,7 @@ from langgraph.graph import StateGraph, START, END
 from langgraph.graph.message import add_messages
 from langchain_core.messages import BaseMessage, SystemMessage, HumanMessage, AIMessage
 from langchain_core.runnables import RunnableConfig
-from langchain_openrouter import ChatOpenRouter
+from langchain_openrouter import ChatOpenRouter #type:ignore
 from typing import TypedDict, Annotated
 
 import sqlite3
@@ -23,9 +23,7 @@ import time
 import json
 import urllib.request
 import threading
-import traceback
-import concurrent.futures
-from langgraph.checkpoint.sqlite import SqliteSaver
+from langgraph.checkpoint.sqlite import SqliteSaver #type:ignore
 from config import OPENROUTER_API_KEY, DB_PATH, LLM_TIMEOUT
 import prompts
 
@@ -284,43 +282,22 @@ def _strip_images(messages: list) -> list:
     return out
 
 
-# ── LLM factory & thread-timeout wrapper ─────────────────────
-#
-# ChatOpenRouter wraps the `openrouter` Python SDK which creates its
-# own httpx.Client internally. That client does NOT inherit the
-# `timeout` kwarg passed to ChatOpenRouter at the LangChain level.
-#
-# Fix: run llm.invoke() in a daemon thread and enforce a hard
-# Python-level deadline with future.result(timeout=LLM_TIMEOUT).
-# This kills the blocked thread from Python's perspective and raises
-# TimeoutError which our retry loop handles like any other error.
-
-# Thread pool — reused across calls to avoid spawn overhead
-_executor = concurrent.futures.ThreadPoolExecutor(max_workers=4)
-
+# ── LLM factory ───────────────────────────────────────────────
 
 def _make_llm(api_key: str, model_id: str):
     key = api_key or OPENROUTER_API_KEY
     if not key:
-        raise ValueError(
-            "No API key available. Please add your OpenRouter key in Settings."
-        )
+        raise ValueError("No API key. Add your OpenRouter key in Settings.")
     return ChatOpenRouter(
         model=model_id,
         openrouter_api_key=key,
         temperature=0.5,
         max_tokens=4096,
-        max_retries=0,       # disable SDK retries — our loop handles rotation
+        max_retries=1,
         streaming=True,
     )
 
 
-def _invoke_with_timeout(llm, messages: list, timeout: float):
-    """Run llm.invoke in a thread; raise TimeoutError after `timeout` seconds."""
-    future = _executor.submit(llm.invoke, messages)
-    return future.result(timeout=timeout)
-
-
 # ── LangGraph state & node ────────────────────────────────────
 
 class ChatState(TypedDict):
@@ -338,62 +315,33 @@ def chat_node(state: ChatState, config: RunnableConfig):
     override  = cfg.get("model", "")
     has_image = cfg.get("has_image", False)
 
-    # 1) Classify
     user_text = _extract_text(state["messages"])
     category  = _classify(user_text)
 
-    # 2) Pick model
     if override:
         model_id, actual = override, category
     else:
         model_id, actual = _pick(category, has_image=has_image)
 
-    # 3) Strip images from history when model is not vision-capable
     messages = state["messages"]
     if actual != "vision":
         messages = _strip_images(messages)
 
-    # 4) Build system prompt
     base_prompt = prompts.build(persona, context, language, username, profile)
 
     if has_image:
         base_prompt += (
             "\n\nIMAGE HANDLING:\n"
-            "The student has attached an image with their question. "
-            "Analyze the image carefully and respond to their question about it. "
-            "Describe what you see in the image if relevant, then answer their query. "
-            "Do NOT output safety classifications, content ratings, or moderation labels. "
-            "You are a teacher — respond with an educational explanation, not a safety assessment.\n"
+            "The student attached an image. Analyze it and respond educationally. "
+            "Do NOT output safety classifications or moderation labels.\n"
         )
 
     sys = SystemMessage(content=base_prompt)
     print(f"[ROUTER] category={category} model={model_id} vision={actual == 'vision'}")
 
-    # 5) Invoke with model rotation + hard Python timeout
-    max_attempts = 3
-    last_error = None
-    for attempt in range(max_attempts):
-        try:
-            llm = _make_llm(api_key, model_id)
-            resp = _invoke_with_timeout(llm, [sys] + messages, timeout=LLM_TIMEOUT)
-            return {"messages": [resp]}
-        except concurrent.futures.TimeoutError:
-            last_error = TimeoutError(f"Model {model_id} timed out after {LLM_TIMEOUT}s")
-            print(f"[ROUTER] TIMEOUT {model_id} after {LLM_TIMEOUT}s (attempt {attempt+1}/{max_attempts})")
-            if attempt < max_attempts - 1:
-                model_id, actual = _pick(category, has_image=has_image)
-                print(f"[ROUTER] Rotating to: {model_id}")
-        except Exception as e:
-            last_error = e
-            print(f"[ROUTER] FAIL {model_id} (attempt {attempt+1}/{max_attempts}): {type(e).__name__}: {str(e)[:200]}")
-            traceback.print_exc()
-            if attempt < max_attempts - 1:
-                model_id, actual = _pick(category, has_image=has_image)
-                print(f"[ROUTER] Rotating to: {model_id}")
-
-    # All attempts failed — raise so app.py SSE handler can show the error
-    print(f"[ROUTER] All {max_attempts} attempts failed. Raising last error.")
-    raise last_error
+    llm = _make_llm(api_key, model_id)
+    resp = llm.invoke([sys] + messages)
+    return {"messages": [resp]}
 
 
 # ── Compile graph ─────────────────────────────────────────────
@@ -404,3 +352,4 @@ _g.add_edge(START, "chat_node")
 _g.add_edge("chat_node", END)
 
 chatbot = _g.compile(checkpointer=checkpointer)
+

static/app.js

@@ -357,13 +357,11 @@ function showApp() {
 
 function enterHeroMode() {
     isHeroMode = true;
-    if (welcomeScreen) welcomeScreen.style.display = '';
     bottomInputContainer.style.display = 'none';
-    const existing = document.getElementById('welcomeScreen');
-    if (!existing) {
-        chatContainer.innerHTML = '';
-        chatContainer.appendChild(createWelcomeScreen());
-    }
+    const old = document.getElementById('welcomeScreen');
+    if (old) old.remove();
+    chatContainer.innerHTML = '';
+    chatContainer.appendChild(createWelcomeScreen());
     _updateHeroTitle();
 }