[Obs AI Assistant] Update the simulate function calling setting to support "auto" (#209628)

Closes elastic/obs-ai-assistant-team#198

## Summary

The simulated function calling setting is currently a boolean. It needs
to be updated to support the option `auto`.
`export type FunctionCallingMode = 'native' | 'simulated' | 'auto';`

If the setting is set to `false`, `auto` will be passed to the inference
client. If the setting is `true`, `simulated` will be passed to it.

Relates to #208144


### Checklist

- [x] Any text added follows [EUI's writing
guidelines](https://elastic.github.io/eui/#/guidelines/writing), uses
sentence case text and includes [i18n
support](https://github.com/elastic/kibana/blob/main/src/platform/packages/shared/kbn-i18n/README.md)
- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios
- [x] The PR description includes the appropriate Release Notes section,
and the correct `release_note:*` label is applied per the
[guidelines](https://www.elastic.co/guide/en/kibana/master/contributing.html#kibana-release-notes-process)

---------

Co-authored-by: kibanamachine <[email protected]>

Author: viduni94

x-pack/platform/packages/shared/kbn-ai-assistant/src/chat/chat_body.tsx

@@ -28,14 +28,14 @@ import {
   VisualizeESQLUserIntention,
   type ChatActionClickPayload,
   type Feedback,
+  aiAssistantSimulatedFunctionCalling,
 } from '@kbn/observability-ai-assistant-plugin/public';
 import type { AuthenticatedUser } from '@kbn/security-plugin/common';
 import { findLastIndex } from 'lodash';
 import React, { useCallback, useEffect, useRef, useState } from 'react';
 import type { UseKnowledgeBaseResult } from '../hooks/use_knowledge_base';
 import { ASSISTANT_SETUP_TITLE, EMPTY_CONVERSATION_TITLE, UPGRADE_LICENSE_TITLE } from '../i18n';
 import { useAIAssistantChatService } from '../hooks/use_ai_assistant_chat_service';
-import { useSimulatedFunctionCalling } from '../hooks/use_simulated_function_calling';
 import { useGenAIConnectors } from '../hooks/use_genai_connectors';
 import { useConversation } from '../hooks/use_conversation';
 import { FlyoutPositionMode } from './chat_flyout';
@@ -47,6 +47,7 @@ import { WelcomeMessage } from './welcome_message';
 import { useLicense } from '../hooks/use_license';
 import { PromptEditor } from '../prompt_editor/prompt_editor';
 import { deserializeMessage } from '../utils/deserialize_message';
+import { useKibana } from '../hooks/use_kibana';
 
 const fullHeightClassName = css`
   height: 100%;
@@ -138,7 +139,14 @@ export function ChatBody({
 
   const chatService = useAIAssistantChatService();
 
-  const { simulatedFunctionCallingEnabled } = useSimulatedFunctionCalling();
+  const {
+    services: { uiSettings },
+  } = useKibana();
+
+  const simulateFunctionCalling = uiSettings!.get<boolean>(
+    aiAssistantSimulatedFunctionCalling,
+    false
+  );
 
   const { conversation, messages, next, state, stop, saveTitle } = useConversation({
     initialConversationId,
@@ -409,7 +417,7 @@ export function ChatBody({
           </div>
         </EuiFlexItem>
 
-        {simulatedFunctionCallingEnabled ? (
+        {simulateFunctionCalling ? (
           <EuiFlexItem grow={false}>
             <SimulatedFunctionCallingCallout />
           </EuiFlexItem>

x-pack/platform/packages/shared/kbn-ai-assistant/src/hooks/use_simulated_function_calling.ts

@@ -50,7 +50,7 @@ describe('chatFunctionClient', () => {
           messages: [],
           signal: new AbortController().signal,
           connectorId: 'foo',
-          useSimulatedFunctionCalling: false,
+          simulateFunctionCalling: false,
         });
       }).rejects.toThrowError(`Function arguments are invalid`);
 
@@ -112,7 +112,7 @@ describe('chatFunctionClient', () => {
         messages: [],
         signal: new AbortController().signal,
         connectorId: 'foo',
-        useSimulatedFunctionCalling: false,
+        simulateFunctionCalling: false,
       });
 
       expect(result).toEqual({

x-pack/platform/plugins/shared/observability_ai_assistant/server/service/chat_function_client/index.test.ts

@@ -167,15 +167,15 @@ export class ChatFunctionClient {
     messages,
     signal,
     connectorId,
-    useSimulatedFunctionCalling,
+    simulateFunctionCalling,
   }: {
     chat: FunctionCallChatFunction;
     name: string;
     args: string | undefined;
     messages: Message[];
     signal: AbortSignal;
     connectorId: string;
-    useSimulatedFunctionCalling: boolean;
+    simulateFunctionCalling: boolean;
   }): Promise<FunctionResponse> {
     const fn = this.functionRegistry.get(name);
 
@@ -194,7 +194,7 @@ export class ChatFunctionClient {
         screenContexts: this.screenContexts,
         chat,
         connectorId,
-        useSimulatedFunctionCalling,
+        simulateFunctionCalling,
       },
       signal
     );

x-pack/platform/plugins/shared/observability_ai_assistant/server/service/chat_function_client/index.ts

@@ -313,7 +313,7 @@ describe('Observability AI Assistant client', () => {
           expect.objectContaining({
             connectorId: 'foo',
             stream: false,
-            functionCalling: 'native',
+            functionCalling: 'auto',
             toolChoice: expect.objectContaining({
               function: 'title_conversation',
             }),
@@ -349,7 +349,7 @@ describe('Observability AI Assistant client', () => {
             messages: expect.arrayContaining([
               { role: 'user', content: 'How many alerts do I have?' },
             ]),
-            functionCalling: 'native',
+            functionCalling: 'auto',
             toolChoice: undefined,
             tools: undefined,
           },
@@ -872,7 +872,7 @@ describe('Observability AI Assistant client', () => {
               },
             },
           ],
-          useSimulatedFunctionCalling: false,
+          simulateFunctionCalling: false,
         });
       });
 
@@ -919,7 +919,7 @@ describe('Observability AI Assistant client', () => {
             messages: expect.arrayContaining([
               { role: 'user', content: 'How many alerts do I have?' },
             ]),
-            functionCalling: 'native',
+            functionCalling: 'auto',
             toolChoice: 'auto',
             tools: expect.any(Object),
           },
@@ -1080,7 +1080,7 @@ describe('Observability AI Assistant client', () => {
             messages: expect.arrayContaining([
               { role: 'user', content: 'How many alerts do I have?' },
             ]),
-            functionCalling: 'native',
+            functionCalling: 'auto',
             toolChoice: 'auto',
             tools: expect.any(Object),
           },

x-pack/platform/plugins/shared/observability_ai_assistant/server/service/client/index.test.ts

@@ -307,7 +307,7 @@ export class ObservabilityAIAssistantClient {
                 disableFunctions,
                 tracer: completeTracer,
                 connectorId,
-                useSimulatedFunctionCalling: simulateFunctionCalling === true,
+                simulateFunctionCalling,
               })
             );
           }),
@@ -505,15 +505,17 @@ export class ObservabilityAIAssistantClient {
           }
         : ToolChoiceType.auto;
     }
+
     const options = {
       connectorId,
       messages: convertMessagesForInference(
         messages.filter((message) => message.message.role !== MessageRole.System)
       ),
       toolChoice,
       tools,
-      functionCalling: (simulateFunctionCalling ? 'simulated' : 'native') as FunctionCallingMode,
+      functionCalling: (simulateFunctionCalling ? 'simulated' : 'auto') as FunctionCallingMode,
     };
+
     if (stream) {
       return defer(() =>
         this.dependencies.inferenceClient.chatComplete({

x-pack/platform/plugins/shared/observability_ai_assistant/server/service/client/index.ts

@@ -54,7 +54,7 @@ function executeFunctionAndCatchError({
   logger,
   tracer,
   connectorId,
-  useSimulatedFunctionCalling,
+  simulateFunctionCalling,
 }: {
   name: string;
   args: string | undefined;
@@ -65,7 +65,7 @@ function executeFunctionAndCatchError({
   logger: Logger;
   tracer: LangTracer;
   connectorId: string;
-  useSimulatedFunctionCalling: boolean;
+  simulateFunctionCalling: boolean;
 }): Observable<MessageOrChatEvent> {
   // hide token count events from functions to prevent them from
   // having to deal with it as well
@@ -86,7 +86,7 @@ function executeFunctionAndCatchError({
           signal,
           messages,
           connectorId,
-          useSimulatedFunctionCalling,
+          simulateFunctionCalling,
         })
       );
 
@@ -184,7 +184,7 @@ export function continueConversation({
   disableFunctions,
   tracer,
   connectorId,
-  useSimulatedFunctionCalling,
+  simulateFunctionCalling,
 }: {
   messages: Message[];
   functionClient: ChatFunctionClient;
@@ -201,7 +201,7 @@ export function continueConversation({
       };
   tracer: LangTracer;
   connectorId: string;
-  useSimulatedFunctionCalling: boolean;
+  simulateFunctionCalling: boolean;
 }): Observable<MessageOrChatEvent> {
   let nextFunctionCallsLeft = functionCallsLeft;
 
@@ -319,7 +319,7 @@ export function continueConversation({
       logger,
       tracer,
       connectorId,
-      useSimulatedFunctionCalling,
+      simulateFunctionCalling,
     });
   }
 
@@ -348,7 +348,7 @@ export function continueConversation({
               disableFunctions,
               tracer,
               connectorId,
-              useSimulatedFunctionCalling,
+              simulateFunctionCalling,
             });
           })
         )

x-pack/platform/plugins/shared/observability_ai_assistant/server/service/client/operators/continue_conversation.ts

@@ -56,7 +56,7 @@ type RespondFunction<TArguments, TResponse extends FunctionResponse> = (
     screenContexts: ObservabilityAIAssistantScreenContextRequest[];
     chat: FunctionCallChatFunction;
     connectorId: string;
-    useSimulatedFunctionCalling: boolean;
+    simulateFunctionCalling: boolean;
   },
   signal: AbortSignal
 ) => Promise<TResponse>;

x-pack/platform/plugins/shared/observability_ai_assistant/server/service/types.ts

@@ -62,14 +62,14 @@ export async function registerDocumentationFunction({
         required: ['query'],
       } as const,
     },
-    async ({ arguments: { query, product }, connectorId, useSimulatedFunctionCalling }) => {
+    async ({ arguments: { query, product }, connectorId, simulateFunctionCalling }) => {
       const response = await llmTasks!.retrieveDocumentation({
         searchTerm: query,
         products: product ? [product] : undefined,
         max: 3,
         connectorId,
         request: resources.request,
-        functionCalling: useSimulatedFunctionCalling ? 'simulated' : 'native',
+        functionCalling: simulateFunctionCalling ? 'simulated' : 'auto',
       });
 
       return {

x-pack/solutions/observability/plugins/observability_ai_assistant_app/server/functions/documentation.ts

@@ -112,7 +112,7 @@ export function registerQueryFunction({
       function takes no input.`,
       visibility: FunctionVisibility.AssistantOnly,
     },
-    async ({ messages, connectorId, useSimulatedFunctionCalling }, signal) => {
+    async ({ messages, connectorId, simulateFunctionCalling }, signal) => {
       const esqlFunctions = functions
         .getFunctions()
         .filter(
@@ -137,7 +137,7 @@ export function registerQueryFunction({
             { description: fn.description, schema: fn.parameters } as ToolDefinition,
           ])
         ),
-        functionCalling: useSimulatedFunctionCalling ? 'simulated' : 'native',
+        functionCalling: simulateFunctionCalling ? 'simulated' : 'auto',
       });
 
       const chatMessageId = v4();