fix: persist assistant tool errors and markdown

backend/server/chat/agent_tools.py

@@ -8,6 +8,7 @@ from django.contrib.contenttypes.models import ContentType
 from django.db import models
 from django.db.models import Q
 from django.utils import timezone
+from rest_framework.exceptions import PermissionDenied, ValidationError
 
 from adventures.models import (
     Collection,
@@ -136,6 +137,23 @@ def _parse_float(value):
         return None
 
 
+def _extract_exception_message(exc, fallback_message):
+    detail = getattr(exc, "detail", None)
+    if isinstance(detail, dict):
+        for value in detail.values():
+            if isinstance(value, (list, tuple)) and value:
+                return str(value[0])
+            if value:
+                return str(value)
+    elif isinstance(detail, (list, tuple)) and detail:
+        return str(detail[0])
+    elif detail:
+        return str(detail)
+
+    message = str(exc).strip()
+    return message or fallback_message
+
+
 def _serialize_lodging(lodging: Lodging):
     return {
         "id": str(lodging.id),
@@ -810,7 +828,23 @@ def move_itinerary_item(
                     }
                 )
 
-        updated_items = reorder_itinerary_items(user, updates)
+        try:
+            updated_items = reorder_itinerary_items(user, updates)
+        except ValidationError as exc:
+            return {
+                "error": _extract_exception_message(
+                    exc,
+                    "Unable to move itinerary item due to invalid itinerary update",
+                )
+            }
+        except PermissionDenied as exc:
+            return {
+                "error": _extract_exception_message(
+                    exc,
+                    "You do not have permission to modify this itinerary item",
+                )
+            }
+
         moved_item = next(
             (item for item in updated_items if str(item.id) == str(itinerary_item.id)),
             itinerary_item,

backend/server/chat/llm_client.py

@@ -33,6 +33,8 @@ When modifying itineraries:
 When chat context includes a trip collection:
 - Treat context as itinerary-wide (potentially multiple stops), not a single destination
 - Use get_trip_details first when you need complete collection context before searching for places
+- Use the active collection_id from context for collection-scoped itinerary management tools (get_trip_details, add_to_itinerary, move_itinerary_item, remove_itinerary_item, update_location_details)
+- Call get_trip_details before move_itinerary_item, remove_itinerary_item, or update_location_details when exact itinerary/location IDs are required, and never invent IDs
 - Ground place searches in trip stops and dates from the provided trip context
 - Only call search_places when you have a concrete, non-empty location string; if location is missing or unclear, ask a clarifying question to obtain it first
 

backend/server/chat/tests.py

@@ -8,6 +8,7 @@ import requests as _requests
 from django.contrib.auth import get_user_model
 from django.contrib.contenttypes.models import ContentType
 from django.test import TestCase
+from rest_framework.exceptions import PermissionDenied, ValidationError
 from rest_framework.test import APITransactionTestCase
 
 from adventures.models import Collection, CollectionItineraryItem, Location, Visit
@@ -459,6 +460,63 @@ class ChatAgentToolItineraryManagementTests(TestCase):
         self.assertEqual(remove_result, {"error": "Trip not found"})
         self.assertEqual(update_result, {"error": "Trip not found"})
 
+    @patch("chat.agent_tools.reorder_itinerary_items")
+    def test_move_itinerary_item_returns_validation_error_from_reorder(
+        self,
+        mock_reorder_itinerary_items,
+    ):
+        mock_reorder_itinerary_items.side_effect = ValidationError(
+            {
+                "items": (
+                    "Item abc date 2026-05-30 is before collection start date "
+                    "2026-06-01."
+                )
+            }
+        )
+
+        self.collection.start_date = date(2026, 6, 1)
+        self.collection.save(update_fields=["start_date"])
+
+        result = move_itinerary_item(
+            self.owner,
+            collection_id=str(self.collection.id),
+            itinerary_item_id=str(self.day1_item.id),
+            date="2026-06-02",
+            order=0,
+        )
+
+        self.assertEqual(
+            result,
+            {
+                "error": (
+                    "Item abc date 2026-05-30 is before collection start date "
+                    "2026-06-01."
+                )
+            },
+        )
+
+    @patch("chat.agent_tools.reorder_itinerary_items")
+    def test_move_itinerary_item_returns_permission_error_from_reorder(
+        self,
+        mock_reorder_itinerary_items,
+    ):
+        mock_reorder_itinerary_items.side_effect = PermissionDenied(
+            "You do not have permission to modify items in this collection."
+        )
+
+        result = move_itinerary_item(
+            self.owner,
+            collection_id=str(self.collection.id),
+            itinerary_item_id=str(self.day1_item.id),
+            date="2026-06-02",
+            order=0,
+        )
+
+        self.assertEqual(
+            result,
+            {"error": "You do not have permission to modify items in this collection."},
+        )
+
 
 class ChatViewSetToolValidationBoundaryTests(TestCase):
     def test_trip_context_destination_summary_normalizes_to_first_segment(self):
@@ -589,6 +647,70 @@ class ChatViewSetToolValidationBoundaryTests(TestCase):
 
 
 class ChatViewSetSearchPlacesClarificationTests(APITransactionTestCase):
+    @patch("chat.views.stream_chat_completion")
+    @patch("integrations.utils.auto_profile.update_auto_preference_profile")
+    def test_collection_context_includes_uuid_guidance_for_existing_item_tools(
+        self,
+        _mock_auto_profile,
+        mock_stream_chat_completion,
+    ):
+        user = User.objects.create_user(
+            username="chat-context-tool-guidance-user",
+            email="chat-context-tool-guidance-user@example.com",
+            password="password123",
+        )
+        self.client.force_authenticate(user=user)
+
+        collection = Collection.objects.create(user=user, name="Paris Trip")
+
+        conversation_response = self.client.post(
+            "/api/chat/conversations/",
+            {"title": "Context Tool Guidance Test"},
+            format="json",
+        )
+        self.assertEqual(conversation_response.status_code, 201)
+        conversation_id = conversation_response.json()["id"]
+
+        async def stream_noop(*args, **kwargs):
+            yield "data: [DONE]\n\n"
+
+        mock_stream_chat_completion.side_effect = stream_noop
+
+        response = self.client.post(
+            f"/api/chat/conversations/{conversation_id}/send_message/",
+            {
+                "message": "Move my first stop to day 2",
+                "collection_id": str(collection.id),
+                "collection_name": collection.name,
+            },
+            format="json",
+        )
+
+        self.assertEqual(response.status_code, 200)
+        list(response.streaming_content)
+
+        stream_call_messages = mock_stream_chat_completion.call_args.args[1]
+        system_message = next(
+            message for message in stream_call_messages if message["role"] == "system"
+        )
+        normalized_system_content = system_message["content"].lower()
+        self.assertIn(
+            (
+                "use this exact collection_id for get_trip_details, "
+                "add_to_itinerary, move_itinerary_item, remove_itinerary_item, "
+                "and update_location_details"
+            ),
+            normalized_system_content,
+        )
+        self.assertIn(
+            (
+                "call get_trip_details first before move_itinerary_item, "
+                "remove_itinerary_item, or update_location_details when exact IDs "
+                "are needed"
+            ).lower(),
+            normalized_system_content,
+        )
+
     @patch("chat.views.execute_tool")
     @patch("chat.views.stream_chat_completion")
     @patch("integrations.utils.auto_profile.update_auto_preference_profile")
@@ -1073,6 +1195,56 @@ class ChatViewSetSearchPlacesClarificationTests(APITransactionTestCase):
 
 
 class ChatViewSetToolExecutionFailureLoopTests(APITransactionTestCase):
+    @patch("chat.views.execute_tool")
+    @patch("chat.views.stream_chat_completion")
+    @patch("integrations.utils.auto_profile.update_auto_preference_profile")
+    def test_required_param_terminal_error_is_persisted_as_assistant_message(
+        self,
+        _mock_auto_profile,
+        mock_stream_chat_completion,
+        mock_execute_tool,
+    ):
+        user = User.objects.create_user(
+            username="chat-required-error-persist-user",
+            email="chat-required-error-persist-user@example.com",
+            password="password123",
+        )
+        self.client.force_authenticate(user=user)
+
+        conversation_response = self.client.post(
+            "/api/chat/conversations/",
+            {"title": "Required Error Persistence Test"},
+            format="json",
+        )
+        self.assertEqual(conversation_response.status_code, 201)
+        conversation_id = conversation_response.json()["id"]
+
+        async def validation_error_stream(*args, **kwargs):
+            yield 'data: {"tool_calls": [{"index": 0, "id": "call_move", "type": "function", "function": {"name": "move_itinerary_item", "arguments": "{}"}}]}\n\n'
+            yield "data: [DONE]\n\n"
+
+        mock_stream_chat_completion.side_effect = validation_error_stream
+        mock_execute_tool.return_value = {
+            "error": "collection_id, itinerary_item_id, and date are required"
+        }
+
+        response = self.client.post(
+            f"/api/chat/conversations/{conversation_id}/send_message/",
+            {"message": "Move that stop"},
+            format="json",
+        )
+
+        self.assertEqual(response.status_code, 200)
+        list(response.streaming_content)
+
+        conversation = user.chat_conversations.get(id=conversation_id)
+        self.assertTrue(
+            conversation.messages.filter(
+                role="assistant",
+                content__contains="attempted to call 'move_itinerary_item' without required arguments",
+            ).exists()
+        )
+
     @patch("chat.views.execute_tool")
     @patch("chat.views.stream_chat_completion")
     @patch("integrations.utils.auto_profile.update_auto_preference_profile")
@@ -1145,6 +1317,14 @@ class ChatViewSetToolExecutionFailureLoopTests(APITransactionTestCase):
         self.assertEqual(mock_stream_chat_completion.call_count, 3)
         self.assertEqual(mock_execute_tool.call_count, 3)
 
+        conversation = user.chat_conversations.get(id=conversation_id)
+        self.assertTrue(
+            conversation.messages.filter(
+                role="assistant",
+                content__contains="could not complete 'web_search'",
+            ).exists()
+        )
+
     @patch("chat.views.execute_tool")
     @patch("chat.views.stream_chat_completion")
     @patch("integrations.utils.auto_profile.update_auto_preference_profile")

backend/server/chat/views/__init__.py

@@ -493,6 +493,13 @@ class ChatViewSet(viewsets.ModelViewSet):
 
         context_parts = []
         itinerary_stops = []
+        collection_id_guidance = ""
+        collection_tool_id_guidance = (
+            "Use this exact collection_id for get_trip_details, add_to_itinerary, "
+            "move_itinerary_item, remove_itinerary_item, and update_location_details. "
+            "Call get_trip_details first before move_itinerary_item, "
+            "remove_itinerary_item, or update_location_details when exact IDs are needed."
+        )
         if collection_name:
             context_parts.append(f"Trip: {collection_name}")
         if start_date and end_date:
@@ -513,10 +520,8 @@ class ChatViewSet(viewsets.ModelViewSet):
                 pass
 
         if collection:
-            context_parts.append(
+            collection_id_guidance = collection_tool_id_guidance
-                "Collection UUID (use this exact collection_id for get_trip_details and add_to_itinerary): "
+            context_parts.append(f"Collection UUID: {collection.id}")
-                f"{collection.id}"
-            )
             seen_stops = set()
             for location in collection.locations.select_related(
                 "city", "country"
@@ -577,6 +582,10 @@ class ChatViewSet(viewsets.ModelViewSet):
         system_prompt = get_system_prompt(request.user, collection)
         if context_parts:
             system_prompt += "\n\n## Trip Context\n" + "\n".join(context_parts)
+        if collection_id_guidance:
+            system_prompt += (
+                "\n\n## Collection Tool Guardrails\n" + collection_id_guidance
+            )
 
         ChatMessage.objects.create(
             conversation=conversation,
@@ -883,6 +892,18 @@ class ChatViewSet(viewsets.ModelViewSet):
                                 function_name,
                                 result,
                             )
+                            await sync_to_async(
+                                ChatMessage.objects.create,
+                                thread_sensitive=True,
+                            )(
+                                conversation=conversation,
+                                role="assistant",
+                                content=error_event["error"],
+                            )
+                            await sync_to_async(
+                                conversation.save,
+                                thread_sensitive=True,
+                            )(update_fields=["updated_at"])
                             yield f"data: {json.dumps(error_event)}\n\n"
                             yield "data: [DONE]\n\n"
                             return

frontend/src/lib/components/AITravelChat.svelte

@@ -2,6 +2,8 @@
 	import { createEventDispatcher, onMount } from 'svelte';
 	import { t } from 'svelte-i18n';
 	import { mdiSend, mdiPlus, mdiDelete, mdiMenu, mdiClose } from '@mdi/js';
+	import { marked } from 'marked';
+	import DOMPurify from 'dompurify';
 	import type { ChatProviderCatalogEntry, CollectionItineraryItem, Location } from '$lib/types.js';
 	import { addToast } from '$lib/toasts';
 
@@ -932,6 +934,14 @@
 			text: `${result.name.replaceAll('_', ' ')} completed.`
 		};
 	}
+
+	function renderMarkdown(markdown: string): string {
+		return marked(markdown) as string;
+	}
+
+	function renderAssistantMarkdown(content: string): string {
+		return DOMPurify.sanitize(renderMarkdown(content));
+	}
 </script>
 
 <div
@@ -1126,7 +1136,13 @@
 												? 'chat-bubble-primary'
 												: 'chat-bubble-neutral'}"
 										>
-											<div class="whitespace-pre-wrap">{msg.content}</div>
+											{#if msg.role === 'assistant'}
+												<div class="assistant-markdown">
+													{@html renderAssistantMarkdown(msg.content)}
+												</div>
+											{:else}
+												<div class="whitespace-pre-wrap break-words">{msg.content}</div>
+											{/if}
 											{#if msg.role === 'assistant' && msg.tool_results}
 												<div class="mt-2 space-y-2">
 													{#each deduplicateContextTools(uniqueToolResultsByCallId(msg.tool_results)) as result}
@@ -1327,3 +1343,56 @@
 		</div>
 	</div>
 {/if}
+
+<style>
+	.assistant-markdown {
+		color: inherit;
+		line-height: 1.5;
+		word-break: break-word;
+	}
+
+	.assistant-markdown :global(p) {
+		margin: 0;
+	}
+
+	.assistant-markdown :global(p + p),
+	.assistant-markdown :global(ul + p),
+	.assistant-markdown :global(ol + p),
+	.assistant-markdown :global(pre + p),
+	.assistant-markdown :global(blockquote + p) {
+		margin-top: 0.5rem;
+	}
+
+	.assistant-markdown :global(ul),
+	.assistant-markdown :global(ol) {
+		margin: 0.5rem 0 0;
+		padding-left: 1.25rem;
+	}
+
+	.assistant-markdown :global(li + li) {
+		margin-top: 0.25rem;
+	}
+
+	.assistant-markdown :global(strong),
+	.assistant-markdown :global(em),
+	.assistant-markdown :global(code),
+	.assistant-markdown :global(a) {
+		color: inherit;
+	}
+
+	.assistant-markdown :global(a) {
+		text-decoration: underline;
+	}
+
+	.assistant-markdown :global(pre) {
+		margin-top: 0.5rem;
+		padding: 0.5rem;
+		border-radius: 0.5rem;
+		background-color: color-mix(in srgb, currentColor 12%, transparent);
+		overflow-x: auto;
+	}
+
+	.assistant-markdown :global(code) {
+		font-size: 0.875em;
+	}
+</style>