emmanuelmathot · Nov 2, 2026
diff --git a/app/components/editor/assistant-tab.tsx b/app/components/editor/assistant-tab.tsx
@@ -134,19 +134,9 @@ function CodeDiff({ change }: { change: CodeChange }) {
   });
 }
 
-/** A question for the assistant from elsewhere in the editor. */
-export interface AskAssistant {
-  text: string;
-  at: number;
-  /** The conversation it was asked in. */
-  thread: string;
-}
-
 export function AssistantTab({
-  ask,
   onAccepted
 }: {
-  ask?: AskAssistant;
   /** Once the last card is decided, if any was accepted: run and save, as the Save button does. */
   onAccepted?: () => void;
 }) {
@@ -160,8 +150,16 @@ export function AssistantTab({
     setBoundingBox,
     setPropertyFilters
   } = useEditorStore();
-  const { items, setItems, busy, setBusy, setUnsaved, reset } =
-    useAssistantStore();
+  const {
+    items,
+    setItems,
+    busy,
+    setBusy,
+    setUnsaved,
+    reset,
+    question,
+    takeQuestion
+  } = useAssistantStore();
   const [draft, setDraft] = useState('');
   const sentCode = useRef('');
   /** The run in flight, which its code cards name. */
@@ -517,15 +515,15 @@ export function AssistantTab({
       item.kind === 'proposal' && item.status === 'pending' && !item.held
   );
 
-  /** The last question from elsewhere that was sent. */
-  const asked = useRef<number>(undefined);
   useEffect(() => {
     // A question asked during a run waits for the run to end. One asked in
     // another conversation is about another project: it is dropped.
-    if (!ask || busy || asked.current === ask.at) return;
-    asked.current = ask.at;
-    if (ask.thread === useAssistantStore.getState().threadId) send(ask.text);
-  }, [ask?.at, busy]);
+    if (!question || busy) return;
+    const taken = takeQuestion();
+    if (taken?.thread === useAssistantStore.getState().threadId) {
+      send(taken.text);
+    }
+  }, [question?.at, busy]);
 
   useEffect(() => {
     end.current?.scrollIntoView({ block: 'end' });

diff --git a/app/components/editor/editor-workspace.tsx b/app/components/editor/editor-workspace.tsx
@@ -12,7 +12,7 @@ import { useCodeEditor } from './code-editor';
 import { useCodeExecution } from './use-code-execution';
 import { ConfigurationTab } from './configuration-tab';
 import { CodeTab } from './code-tab';
-import { AssistantTab, type AskAssistant } from './assistant-tab';
+import { AssistantTab } from './assistant-tab';
 import { appConfig } from '$config/runtime';
 import { ExecutionErrorAlert } from './execution-error-alert';
 import { EditorHeader } from './editor-header';
@@ -64,7 +64,11 @@ export function EditorWorkspace({
 
   const [activeTab, setActiveTab] = useState<EditorTabId>(defaultTab);
   const [isErrorDismissed, setIsErrorDismissed] = useState(false);
-  const [ask, setAsk] = useState<AskAssistant>();
+  // A question from an error, here or on the map, opens the Assistant tab.
+  const question = useAssistantStore((state) => state.question);
+  useEffect(() => {
+    if (question) setActiveTab('assistant');
+  }, [question?.at]);
   // Set when the assistant's change is accepted; the save waits for the render that carries the
   // accepted configuration, which the execution hook reads from props.
   const [saveAfterAccept, setSaveAfterAccept] = useState(false);
@@ -219,10 +223,7 @@ export function EditorWorkspace({
             p={4}
             bg='bg'
           >
-            <AssistantTab
-              ask={ask}
-              onAccepted={() => setSaveAfterAccept(true)}
-            />
+            <AssistantTab onAccepted={() => setSaveAfterAccept(true)} />
           </Tabs.Content>
         </Stack>
 
@@ -233,12 +234,11 @@ export function EditorWorkspace({
             onAsk={
               appConfig.agentUrl
                 ? () => {
-                    setAsk({
-                      text: `My code failed to run. Why, and how do I fix it?\n\n${useEditorStore.getState().lastRun?.error ?? errorMessage}`,
-                      at: Date.now(),
-                      thread: useAssistantStore.getState().threadId
-                    });
-                    setActiveTab('assistant');
+                    useAssistantStore
+                      .getState()
+                      .ask(
+                        `My code failed to run. Why, and how do I fix it?\n\n${useEditorStore.getState().lastRun?.error ?? errorMessage}`
+                      );
                     setIsErrorDismissed(true);
                   }
                 : undefined

diff --git a/app/components/editor/results-panel.tsx b/app/components/editor/results-panel.tsx
@@ -21,6 +21,8 @@ import { LuCodeXml, LuDownload, LuMap, LuWorkflow } from 'react-icons/lu';
 
 import type { ServiceInfo } from '$types';
 import type { ProcessGraph } from '$types/openeo-process';
+import { appConfig } from '$config/runtime';
+import { useAssistantStore } from '$stores/assistant-store';
 import { useEditorStore } from '$stores/editor-store';
 import { MapViewer } from '$components/map/map-viewer';
 import { TileStatusAlert } from '$components/map/tile-status-alert';
@@ -46,7 +48,8 @@ function ResultsPanelComponent() {
       services: state.services
     }))
   );
-  const { toggleServiceVisibility, setBoundingBox } = useEditorStore();
+  const { toggleServiceVisibility, setBoundingBox, setTileError } =
+    useEditorStore();
 
   const [tileStatus, setTileStatus] = useState<TileLoadStatus>({
     pending: 0,
@@ -62,6 +65,19 @@ function ResultsPanelComponent() {
     }
   }, [services.length, tileStatus.status]);
 
+  // The assistant reads the tile error of the view from the store. A new view
+  // or a new run sets the status again, so an old error goes with it.
+  const tileError =
+    tileStatus.status === 'error' ? tileStatus.error : undefined;
+  const failed = tileStatus.failed ?? 1;
+  useEffect(() => {
+    setTileError(
+      tileError
+        ? { code: tileError.code, message: tileError.message, failed }
+        : null
+    );
+  }, [tileError?.code, tileError?.message, failed, setTileError]);
+
   return (
     <Stack gap={0} flexGrow={1} h='100%' position='relative' asChild>
       <Tabs.Root defaultValue='map' variant='subtle' size='sm' lazyMount>
@@ -121,7 +137,21 @@ function ResultsPanelComponent() {
                 onServicePublish={(v) => setShareService(v)}
               />
             </Flex>
-            {services.length > 0 && <TileStatusAlert status={tileStatus} />}
+            {services.length > 0 && (
+              <TileStatusAlert
+                status={tileStatus}
+                onAsk={
+                  appConfig.agentUrl && tileError
+                    ? () =>
+                        useAssistantStore
+                          .getState()
+                          .ask(
+                            `My map shows tile errors. Why, and how do I fix it?\n\n${failed} tile(s) failed: ${tileError.code}: ${tileError.message}`
+                          )
+                    : undefined
+                }
+              />
+            )}
 
             {shareService && (
               <ShareDialog

diff --git a/app/components/map/tile-status-alert.tsx b/app/components/map/tile-status-alert.tsx
@@ -1,11 +1,13 @@
-import { Alert, ProgressCircle, Box, Text } from '@chakra-ui/react';
+import { Alert, ProgressCircle, Box, Button, Text } from '@chakra-ui/react';
 import type { TileLoadStatus } from './use-map-tile-status';
 
 interface TileStatusAlertProps {
   status: TileLoadStatus;
+  /** Asks the assistant about the tile error. Absent when no assistant is configured. */
+  onAsk?: () => void;
 }
 
-export function TileStatusAlert({ status }: TileStatusAlertProps) {
+export function TileStatusAlert({ status, onAsk }: TileStatusAlertProps) {
   if (status.status === 'idle') return null;
 
   if (status.status === 'error' && status.error) {
@@ -25,6 +27,11 @@ export function TileStatusAlert({ status }: TileStatusAlertProps) {
                 {error.message}
               </Text>
             </Alert.Description>
+            {onAsk && (
+              <Button size='xs' variant='outline' mt={2} onClick={onAsk}>
+                Ask the assistant
+              </Button>
+            )}
           </Alert.Content>
         </Alert.Root>
       </Box>

diff --git a/app/stores/assistant-store.ts b/app/stores/assistant-store.ts
@@ -41,6 +41,14 @@ export type Item =
       change: CodeChange | ConfigurationChange;
     };
 
+/** A question for the assistant from elsewhere in the editor: an error. */
+export interface AskAssistant {
+  text: string;
+  at: number;
+  /** The conversation it was asked in. */
+  thread: string;
+}
+
 /**
  * The proposals still waiting for a decision, superseded: the user asked
  * again instead of deciding them. Accepting one later would apply what the
@@ -68,12 +76,18 @@ type AssistantState = {
   unsaved: boolean;
   /** The saved project the conversation is about; null for an unsaved one. */
   project: string | null;
+  /** The last question asked from elsewhere in the editor. Not persisted. */
+  question: AskAssistant | null;
 };
 
 type AssistantActions = {
   setItems: (change: (items: Item[]) => Item[]) => void;
   setBusy: (busy: boolean) => void;
   setUnsaved: (unsaved: boolean) => void;
+  /** Asks the assistant from elsewhere in the editor: the tab sends it. */
+  ask: (text: string) => void;
+  /** The question waiting to be sent, which is then no longer waiting. */
+  takeQuestion: () => AskAssistant | null;
   /** A new conversation about the same project. */
   reset: () => void;
   /** The project changed: a new conversation, unless it is this one's. */
@@ -87,7 +101,8 @@ const fresh = () => ({
   threadId: crypto.randomUUID(),
   items: [],
   busy: false,
-  unsaved: false
+  unsaved: false,
+  question: null
 });
 
 export const useAssistantStore = create<AssistantState & AssistantActions>()(
@@ -98,6 +113,15 @@ export const useAssistantStore = create<AssistantState & AssistantActions>()(
       setItems: (change) => set((state) => ({ items: change(state.items) })),
       setBusy: (busy) => set({ busy }),
       setUnsaved: (unsaved) => set({ unsaved }),
+      ask: (text) =>
+        set((state) => ({
+          question: { text, at: Date.now(), thread: state.threadId }
+        })),
+      takeQuestion: () => {
+        const { question } = get();
+        set({ question: null });
+        return question;
+      },
       reset: () => set(fresh()),
       forProject: (project) => {
         if (project !== null && get().project === project) return;

diff --git a/app/stores/editor-store.ts b/app/stores/editor-store.ts
@@ -20,6 +20,16 @@ export type LastRun = {
   at?: string;
 };
 
+/** The last tile error of the map view, for the assistant. Not persisted. */
+export type TileError = {
+  code: string;
+  message: string;
+  /** The number of tiles that failed in the view. */
+  failed: number;
+  /** When it was seen, as ISO 8601; stamped by setTileError. */
+  at?: string;
+};
+
 type ConfigValues = EditorConfigValues;
 
 const DEFAULT_SCENE_NAME = 'New Project';
@@ -34,6 +44,7 @@ type EditorState = {
   sceneId: string | null;
   sceneName: string;
   lastRun: LastRun | null;
+  tileError: TileError | null;
   /** Counts the projects opened: a run of an earlier one must not set
    * `lastRun`. Not persisted. */
   opened: number;
@@ -44,6 +55,7 @@ type ResetDefaults = Partial<ConfigValues>;
 type EditorActions = {
   setCode: (code: string) => void;
   setLastRun: (lastRun: LastRun | null) => void;
+  setTileError: (tileError: TileError | null) => void;
   setCollectionId: (id: string) => void;
   setTemporalRange: (range: [string, string]) => void;
   setPropertyFilters: (filters: PropertyFilter[]) => void;
@@ -89,8 +101,16 @@ export const useEditorStore = create<EditorStore>()(
       sceneId: null,
       sceneName: DEFAULT_SCENE_NAME,
       lastRun: null,
+      tileError: null,
       opened: 0,
       setCode: (code) => set((state) => ({ code, ...changed(state) })),
+      setTileError: (tileError) =>
+        set({
+          tileError: tileError && {
+            ...tileError,
+            at: new Date().toISOString()
+          }
+        }),
       setLastRun: (lastRun) =>
         set({
           lastRun: lastRun && { ...lastRun, at: new Date().toISOString() }
@@ -150,6 +170,7 @@ export const useEditorStore = create<EditorStore>()(
           selectedConfig: newConfig,
           services: [],
           lastRun: null,
+          tileError: null,
           opened: state.opened + 1,
           sceneName: DEFAULT_SCENE_NAME
         }));
@@ -163,6 +184,7 @@ export const useEditorStore = create<EditorStore>()(
           selectedConfig: initialConfig,
           services: [],
           lastRun: null,
+          tileError: null,
           opened: state.opened + 1,
           sceneId: null,
           sceneName: DEFAULT_SCENE_NAME
@@ -185,6 +207,7 @@ export const useEditorStore = create<EditorStore>()(
           isDirty: false,
           services: [],
           lastRun: null,
+          tileError: null,
           opened: state.opened + 1
         }));
       }

diff --git a/app/types/agent-contract.schema.json b/app/types/agent-contract.schema.json
@@ -86,6 +86,24 @@
       "additionalProperties": false,
       "description": "One error from the openEO `/validation` endpoint."
     },
+    "TileDiagnostic": {
+      "type": "object",
+      "properties": {
+        "code": {
+          "type": "string",
+          "description": "The openEO error code, for example `NoDataAvailable`."
+        },
+        "message": { "type": "string" },
+        "failed": {
+          "type": "number",
+          "description": "The number of tiles that failed in the view."
+        },
+        "at": { "type": "string" }
+      },
+      "required": ["code", "message", "failed", "at"],
+      "additionalProperties": false,
+      "description": "The last tile error of the current map view, as the backend sent it: the run built a valid graph, but the backend could not compute a tile. Since contract 1.1."
+    },
     "StudioDiagnostics": {
       "type": "object",
       "properties": {
@@ -102,6 +120,13 @@
         "lint": {
           "type": "array",
           "items": { "$ref": "#/definitions/LintDiagnostic" }
+        },
+        "tiles": {
+          "anyOf": [
+            { "$ref": "#/definitions/TileDiagnostic" },
+            { "type": "null" }
+          ],
+          "description": "Since contract 1.1."
         }
       },
       "required": ["execution", "validation", "lint"],
@@ -348,6 +373,7 @@
         "editor.executionError",
         "editor.validationError",
         "editor.lintDiagnostic",
+        "map.tileError",
         "home.kickstart"
       ]
     },