feat: improve AI chat - system prompt, tool output, context window display (#17769)

⚠️ **AI-generated PR — not ready for review** ⚠️

cc @FelixMalfait

---

## Changes

### System prompt improvements
- Explicit skill-before-tools workflow to prevent the model from calling
tools without loading the matching skill first
- Data efficiency guidance (default small limits, use filters)
- Pluralized `load_skill` → `load_skills` for consistency with
`load_tools`

### Token usage reduction
- Output serialization layer: strips null/undefined/empty values from
tool results
- Lowered default `find_*` limit from 100 → 10, max from 1000 → 100

### System object tool generation
- System objects (calendar events, messages, etc.) now generate AI tools
- Only workflow-related and favorite-related objects are excluded

### Context window display fix
- **Bug**: UI compared cumulative tokens (sum of all turns) against
single-request context window → showed 100% after a few turns
- **Fix**: Track `conversationSize` (last step's `inputTokens`) which
represents the actual conversation history size sent to the model
- New `conversationSize` column on thread entity with migration

### Workspace AI instructions
- Support for custom workspace-level AI instructions

---------

Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>

packages/twenty-front/src/modules/ai/utils/__tests__/groupThreadsByDate.test.ts

@@ -8,6 +8,7 @@ describe('groupThreadsByDate', () => {
     totalInputTokens: 0,
     totalOutputTokens: 0,
     contextWindowTokens: null,
+    conversationSize: 0,
     totalInputCredits: 0,
     totalOutputCredits: 0,
   };

packages/twenty-front/src/modules/ai/utils/getToolDisplayMessage.ts

@@ -0,0 +1,99 @@
+import { type ToolInput } from '@/ai/types/ToolInput';
+import { isDefined } from 'twenty-shared/utils';
+
+const extractSearchQuery = (input: ToolInput): string => {
+  if (!input) {
+    return '';
+  }
+
+  if (
+    typeof input === 'object' &&
+    'query' in input &&
+    typeof input.query === 'string'
+  ) {
+    return input.query;
+  }
+
+  if (
+    typeof input === 'object' &&
+    'action' in input &&
+    isDefined(input.action) &&
+    typeof input.action === 'object' &&
+    'query' in input.action &&
+    typeof input.action.query === 'string'
+  ) {
+    return input.action.query;
+  }
+
+  return '';
+};
+
+const extractLoadingMessage = (input: ToolInput): string => {
+  if (
+    isDefined(input) &&
+    typeof input === 'object' &&
+    'loadingMessage' in input &&
+    typeof input.loadingMessage === 'string'
+  ) {
+    return input.loadingMessage;
+  }
+
+  return 'Processing...';
+};
+
+export const resolveToolInput = (
+  input: ToolInput,
+  toolName: string,
+): { resolvedInput: ToolInput; resolvedToolName: string } => {
+  if (
+    toolName === 'execute_tool' &&
+    isDefined(input) &&
+    typeof input === 'object' &&
+    'toolName' in input &&
+    'arguments' in input
+  ) {
+    return {
+      resolvedInput: input.arguments as ToolInput,
+      resolvedToolName: String(input.toolName),
+    };
+  }
+
+  return { resolvedInput: input, resolvedToolName: toolName };
+};
+
+const extractLearnToolNames = (input: ToolInput): string => {
+  if (
+    isDefined(input) &&
+    typeof input === 'object' &&
+    'toolNames' in input &&
+    Array.isArray(input.toolNames)
+  ) {
+    return input.toolNames.join(', ');
+  }
+
+  return '';
+};
+
+export const getToolDisplayMessage = (
+  input: ToolInput,
+  toolName: string,
+  isFinished?: boolean,
+): string => {
+  const { resolvedInput, resolvedToolName } = resolveToolInput(input, toolName);
+
+  if (resolvedToolName === 'web_search') {
+    const query = extractSearchQuery(resolvedInput);
+    const action = isFinished ? 'Searched' : 'Searching';
+
+    return query ? `${action} the web for '${query}'` : `${action} the web`;
+  }
+
+  if (resolvedToolName === 'learn_tools') {
+    const names = extractLearnToolNames(resolvedInput);
+    const action = isFinished ? 'Learned' : 'Learning';
+
+    return names ? `${action} ${names}` : `${action} tools...`;
+  }
+
+  return extractLoadingMessage(resolvedInput);
+};

packages/twenty-front/src/modules/ai/utils/getToolIcon.ts

@@ -1,6 +1,16 @@
-import { IconDatabase, IconMail, IconTool, IconWorld } from 'twenty-ui/display';
+import {
+  IconBook2,
+  IconDatabase,
+  IconMail,
+  IconTool,
+  IconWorld,
+} from 'twenty-ui/display';
 
 const TOOL_ICON_MAPPINGS = [
+  {
+    keywords: ['learn_tools'],
+    icon: IconBook2,
+  },
   {
     keywords: ['email'],
     icon: IconMail,

packages/twenty-front/src/modules/ai/utils/getWebSearchToolDisplayMessage.ts

@@ -1,56 +0,0 @@
-import { type ToolInput } from '@/ai/types/ToolInput';
-import { isDefined } from 'twenty-shared/utils';
-
-const extractSearchQuery = (input: ToolInput): string => {
-  if (!input) {
-    return '';
-  }
-
-  if (
-    typeof input === 'object' &&
-    'query' in input &&
-    typeof input.query === 'string'
-  ) {
-    return input.query;
-  }
-
-  if (
-    typeof input === 'object' &&
-    'action' in input &&
-    isDefined(input.action) &&
-    typeof input.action === 'object' &&
-    'query' in input.action &&
-    typeof input.action.query === 'string'
-  ) {
-    return input.action.query;
-  }
-
-  return '';
-};
-
-const extractLoadingMessage = (input: ToolInput): string => {
-  if (
-    isDefined(input) &&
-    typeof input === 'object' &&
-    'loadingMessage' in input &&
-    typeof input.loadingMessage === 'string'
-  ) {
-    return input.loadingMessage;
-  }
-
-  return 'Processing...';
-};
-
-export const getToolDisplayMessage = (
-  input: ToolInput,
-  toolName: string,
-  isFinished?: boolean,
-): string => {
-  if (toolName === 'web_search') {
-    const query = extractSearchQuery(input);
-    const action = isFinished ? 'Searched' : 'Searching';
-    return query ? `${action} the web for '${query}'` : `${action} the web`;
-  }
-
-  return extractLoadingMessage(input);
-};