Add better error handling for diagram output, and fix chat history construct

- Make the `clean_json` method more robust as well

src/interface/web/app/common/iconUtils.tsx

@@ -215,6 +215,10 @@ export function getIconForSlashCommand(command: string, customClassName: string
         return <PencilLine className={className} />;
     }
 
+    if (command.includes("code")) {
+        return <Code className={className} />;
+    }
+
     return <ArrowRight className={className} />;
 }
 

src/khoj/processor/conversation/utils.py

@@ -5,6 +5,7 @@ import math
 import mimetypes
 import os
 import queue
+import re
 import uuid
 from dataclasses import dataclass
 from datetime import datetime
@@ -377,8 +378,10 @@ def generate_chatml_messages_with_context(
         message_context = ""
         message_attached_files = ""
 
+        chat_message = chat.get("message")
+
         if chat["by"] == "khoj" and "excalidraw" in chat["intent"].get("type", ""):
-            message_context += chat.get("intent").get("inferred-queries")[0]
+            chat_message = chat["intent"].get("inferred-queries")[0]
         if not is_none_or_empty(chat.get("context")):
             references = "\n\n".join(
                 {
@@ -407,7 +410,7 @@ def generate_chatml_messages_with_context(
 
         role = "user" if chat["by"] == "you" else "assistant"
         message_content = construct_structured_message(
-            chat["message"], chat.get("images"), model_type, vision_enabled, attached_file_context=query_files
+            chat_message, chat.get("images"), model_type, vision_enabled, attached_file_context=query_files
         )
 
         reconstructed_message = ChatMessage(content=message_content, role=role)
@@ -524,7 +527,25 @@ def reciprocal_conversation_to_chatml(message_pair):
 
 def clean_json(response: str):
     """Remove any markdown json codeblock and newline formatting if present. Useful for non schema enforceable models"""
-    return response.strip().replace("\n", "").removeprefix("```json").removesuffix("```")
+    try:
+        # Remove markdown code blocks
+        cleaned = response.strip().replace("```json", "").replace("```", "")
+
+        # Find JSON array/object pattern
+        json_match = re.search(r"\[.*\]|\{.*\}", cleaned, re.DOTALL)
+        if not json_match:
+            return ""
+
+        # Extract matched JSON
+        json_str = json_match.group()
+
+        # Validate by parsing
+        json.loads(json_str)
+
+        return json_str.strip()
+
+    except (json.JSONDecodeError, AttributeError):
+        return ""
 
 
 def clean_code_python(code: str):

src/khoj/routers/api_chat.py

@@ -1171,8 +1171,13 @@ async def chat(
                     yield result[ChatEvent.STATUS]
                 else:
                     better_diagram_description_prompt, excalidraw_diagram_description = result
+                    if better_diagram_description_prompt and excalidraw_diagram_description:
                         inferred_queries.append(better_diagram_description_prompt)
                         diagram_description = excalidraw_diagram_description
+                    else:
+                        async for result in send_llm_response(f"Failed to generate diagram. Please try again later."):
+                            yield result
+                        return
 
             content_obj = {
                 "intentType": intent_type,

src/khoj/routers/helpers.py

@@ -784,13 +784,17 @@ async def generate_excalidraw_diagram(
     if send_status_func:
         async for event in send_status_func(f"**Diagram to Create:**:\n{better_diagram_description_prompt}"):
             yield {ChatEvent.STATUS: event}
-
+    try:
         excalidraw_diagram_description = await generate_excalidraw_diagram_from_description(
             q=better_diagram_description_prompt,
             user=user,
             agent=agent,
             tracer=tracer,
         )
+    except Exception as e:
+        logger.error(f"Error generating Excalidraw diagram for {user.email}: {e}", exc_info=True)
+        yield None, None
+        return
 
     yield better_diagram_description_prompt, excalidraw_diagram_description
 
@@ -876,7 +880,10 @@ async def generate_excalidraw_diagram_from_description(
             query=excalidraw_diagram_generation, user=user, tracer=tracer
         )
         raw_response = clean_json(raw_response)
+        try:
             response: Dict[str, str] = json.loads(raw_response)
+        except Exception:
+            raise AssertionError(f"Invalid response for generating Excalidraw diagram: {raw_response}")
         if not response or not isinstance(response, List) or not isinstance(response[0], Dict):
             # TODO Some additional validation here that it's a valid Excalidraw diagram
             raise AssertionError(f"Invalid response for improving diagram description: {response}")