feat: generic web search driver abstraction with Exa support and billing (#19341)

## Summary - Introduces a pluggable `WebSearchDriver` abstraction (interface, factory, service, module) so web search is no longer tied to native provider tools (Anthropic/OpenAI) - **Exa** is the first driver implementation with support for category-filtered search (company, people, news, research paper, etc.) — particularly useful for CRM workflows - Per-query billing for both Exa ($0.007/query) and native provider surcharges ($0.01/query for Anthropic/OpenAI) via the existing `USAGE_RECORDED` pipeline - New config variables: `WEB_SEARCH_DRIVER` (EXA/DISABLED), `EXA_API_KEY`, `WEB_SEARCH_PREFER_NATIVE` (default false — prefers Exa over native when both available) - `WEB_SEARCH` operation type added for usage tracking and Stripe metering ### Architecture ``` WebSearchDriver (interface) ├── ExaDriver — Exa neural search with category support └── DisabledDriver — throws when search is disabled WebSearchDriverFactory (extends DriverFactoryBase) └── creates driver based on WEB_SEARCH_DRIVER config WebSearchService (facade) ├── search(query, options?, billingContext?) ├── isEnabled() └── emits USAGE_RECORDED events per query WebSearchTool (Tool implementation) └── registered in ActionToolProvider, available via tool catalog ``` ### Native search billing gap fixed Anthropic and OpenAI both charge $0.01/search on top of token costs. The token costs were already billed, but the per-call surcharge was not. Added `countNativeWebSearchCallsFromSteps` utility + `billNativeWebSearchUsage` to `AiBillingService`, wired into both chat and workflow agent paths. ## Test plan - [ ] Set `WEB_SEARCH_DRIVER=EXA` + `EXA_API_KEY=...` and verify AI chat can search the web - [ ] Verify category parameter works (ask about a specific company/person) - [ ] Set `WEB_SEARCH_DRIVER=DISABLED` and verify search tool is not exposed - [ ] Set `WEB_SEARCH_PREFER_NATIVE=true` with Anthropic model and verify native search is used - [ ] Verify usage events are emitted in ClickHouse for both Exa and native search paths - [ ] Verify existing billing tests pass (`npx jest ai-billing.service.spec.ts`) Made with [Cursor](https://cursor.com) --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>
2026-04-06 12:02:46 +02:00
parent 8acfacc69c
commit ea572975d8
34 changed files with 575 additions and 22 deletions
@@ -23,6 +23,7 @@ import { TimelineCalendarEventModule } from 'src/engine/core-modules/calendar/ti
 import { CaptchaModule } from 'src/engine/core-modules/captcha/captcha.module';
 import { CloudflareModule } from 'src/engine/core-modules/cloudflare/cloudflare.module';
 import { CodeInterpreterModule } from 'src/engine/core-modules/code-interpreter/code-interpreter.module';
+import { WebSearchModule } from 'src/engine/core-modules/web-search/web-search.module';
 import { DnsManagerModule } from 'src/engine/core-modules/dns-manager/dns-manager.module';
 import { EmailModule } from 'src/engine/core-modules/email/email.module';
 import { EmailingDomainModule } from 'src/engine/core-modules/emailing-domain/emailing-domain.module';
@@ -146,6 +147,7 @@ import { FileModule } from './file/file.module';
    AiBillingModule,
    LogicFunctionModule.forRoot(),
    CodeInterpreterModule.forRoot(),
+    WebSearchModule.forRoot(),
    SearchModule,
    ApiKeyModule,
    PageLayoutModule,
@@ -19,8 +19,10 @@ import { SendEmailTool } from 'src/engine/core-modules/tool/tools/email-tool/sen
 import { HttpTool } from 'src/engine/core-modules/tool/tools/http-tool/http-tool';
 import { NavigateAppTool } from 'src/engine/core-modules/tool/tools/navigate-tool/navigate-app-tool';
 import { SearchHelpCenterTool } from 'src/engine/core-modules/tool/tools/search-help-center-tool/search-help-center-tool';
+import { WebSearchTool } from 'src/engine/core-modules/tool/tools/web-search-tool/web-search-tool';
 import { type ToolInput } from 'src/engine/core-modules/tool/types/tool-input.type';
 import { type Tool } from 'src/engine/core-modules/tool/types/tool.type';
+import { WebSearchService } from 'src/engine/core-modules/web-search/web-search.service';
 import { PermissionsService } from 'src/engine/metadata-modules/permissions/permissions.service';

@Injectable()
@@ -36,7 +38,9 @@ export class ActionToolProvider implements ToolProvider {
    private readonly searchHelpCenterTool: SearchHelpCenterTool,
    private readonly codeInterpreterTool: CodeInterpreterTool,
    private readonly navigateAppTool: NavigateAppTool,
+    private readonly webSearchTool: WebSearchTool,
    private readonly codeInterpreterService: CodeInterpreterService,
+    private readonly webSearchService: WebSearchService,
    private readonly permissionsService: PermissionsService,
    private readonly toolExecutorService: ToolExecutorService,
  ) {
@@ -47,6 +51,7 @@ export class ActionToolProvider implements ToolProvider {
      ['search_help_center', this.searchHelpCenterTool],
      ['code_interpreter', this.codeInterpreterTool],
      ['navigate_app', this.navigateAppTool],
+      ['web_search', this.webSearchTool],
    ]);

    // Register each action tool as a static handler in the executor
@@ -141,6 +146,12 @@ export class ActionToolProvider implements ToolProvider {
      );
    }

+    if (this.webSearchService.isEnabled()) {
+      descriptors.push(
+        this.buildDescriptor('web_search', this.webSearchTool, includeSchemas),
+      );
+    }
+
    return descriptors;
  }

@@ -7,6 +7,7 @@ import { type NativeToolProvider } from 'src/engine/core-modules/tool-provider/i
 import { type ToolProviderContext } from 'src/engine/core-modules/tool-provider/interfaces/tool-provider-context.type';

 import { ToolCategory } from 'twenty-shared/ai';
+import { WebSearchService } from 'src/engine/core-modules/web-search/web-search.service';
 import { AgentModelConfigService } from 'src/engine/metadata-modules/ai/ai-models/services/agent-model-config.service';
 import { AiModelRegistryService } from 'src/engine/metadata-modules/ai/ai-models/services/ai-model-registry.service';

@@ -19,6 +20,7 @@ export class NativeModelToolProvider implements NativeToolProvider {
  constructor(
    private readonly agentModelConfigService: AgentModelConfigService,
    private readonly aiModelRegistryService: AiModelRegistryService,
+    private readonly webSearchService: WebSearchService,
  ) {}

  async isAvailable(context: ToolProviderContext): Promise<boolean> {
@@ -30,6 +32,10 @@ export class NativeModelToolProvider implements NativeToolProvider {
      return {};
    }

+    if (!this.webSearchService.shouldUseNativeSearch()) {
+      return {};
+    }
+
    const registeredModel =
      await this.aiModelRegistryService.resolveModelForAgent(context.agent);

@@ -14,6 +14,7 @@ import { SendEmailTool } from 'src/engine/core-modules/tool/tools/email-tool/sen
 import { HttpTool } from 'src/engine/core-modules/tool/tools/http-tool/http-tool';
 import { NavigateAppTool } from 'src/engine/core-modules/tool/tools/navigate-tool/navigate-app-tool';
 import { SearchHelpCenterTool } from 'src/engine/core-modules/tool/tools/search-help-center-tool/search-help-center-tool';
+import { WebSearchTool } from 'src/engine/core-modules/tool/tools/web-search-tool/web-search-tool';
 import { WorkspaceManyOrAllFlatEntityMapsCacheModule } from 'src/engine/metadata-modules/flat-entity/services/workspace-many-or-all-flat-entity-maps-cache.module';
 import { ConnectedAccountEntity } from 'src/engine/metadata-modules/connected-account/entities/connected-account.entity';
 import { NavigationMenuItemModule } from 'src/engine/metadata-modules/navigation-menu-item/navigation-menu-item.module';
@@ -45,6 +46,7 @@ import { MessagingSendManagerModule } from 'src/modules/messaging/message-outbou
    SearchHelpCenterTool,
    CodeInterpreterTool,
    NavigateAppTool,
+    WebSearchTool,
  ],
  exports: [
    HttpTool,
@@ -54,6 +56,7 @@ import { MessagingSendManagerModule } from 'src/modules/messaging/message-outbou
    SearchHelpCenterTool,
    CodeInterpreterTool,
    NavigateAppTool,
+    WebSearchTool,
  ],
 })
 export class ToolModule {}
@@ -0,0 +1,5 @@
+import { type z } from 'zod';
+
+import { type WebSearchInputZodSchema } from 'src/engine/core-modules/tool/tools/web-search-tool/web-search-tool.schema';
+
+export type WebSearchInput = z.infer<typeof WebSearchInputZodSchema>;
@@ -0,0 +1,29 @@
+import { z } from 'zod';
+
+import { WEB_SEARCH_CATEGORIES } from 'src/engine/core-modules/web-search/constants/web-search-categories.const';
+
+export const WEB_SEARCH_DEFAULT_NUM_RESULTS = 10;
+export const WEB_SEARCH_MAX_NUM_RESULTS = 30;
+
+export const WebSearchInputZodSchema = z.object({
+  query: z
+    .string()
+    .describe(
+      'The search query to look up on the web. Be specific and include relevant keywords for better results.',
+    ),
+  category: z
+    .enum(WEB_SEARCH_CATEGORIES)
+    .optional()
+    .describe(
+      'Optional content category to focus the search. Use "company" for business/organization info, "people" for person profiles, "news" for recent articles, "research paper" for academic content.',
+    ),
+  numResults: z
+    .number()
+    .int()
+    .min(1)
+    .max(WEB_SEARCH_MAX_NUM_RESULTS)
+    .optional()
+    .describe(
+      `Number of search results to return. Defaults to ${WEB_SEARCH_DEFAULT_NUM_RESULTS}, max ${WEB_SEARCH_MAX_NUM_RESULTS}. Use more results when you need comprehensive coverage.`,
+    ),
+});
@@ -0,0 +1,48 @@
+import { Injectable } from '@nestjs/common';
+
+import { type WebSearchInput } from 'src/engine/core-modules/tool/tools/web-search-tool/web-search-input.type';
+import { WebSearchInputZodSchema } from 'src/engine/core-modules/tool/tools/web-search-tool/web-search-tool.schema';
+import { type ToolExecutionContext } from 'src/engine/core-modules/tool/types/tool-execution-context.type';
+import { type ToolInput } from 'src/engine/core-modules/tool/types/tool-input.type';
+import { type ToolOutput } from 'src/engine/core-modules/tool/types/tool-output.type';
+import { type Tool } from 'src/engine/core-modules/tool/types/tool.type';
+import { WebSearchService } from 'src/engine/core-modules/web-search/web-search.service';
+
+@Injectable()
+export class WebSearchTool implements Tool {
+  description =
+    'Search the web for real-time information. Returns relevant results with titles, URLs, and content snippets. Supports optional category filtering for company, people, news, and other content types.';
+  inputSchema = WebSearchInputZodSchema;
+
+  constructor(private readonly webSearchService: WebSearchService) {}
+
+  async execute(
+    parameters: ToolInput,
+    context: ToolExecutionContext,
+  ): Promise<ToolOutput> {
+    const { query, category, numResults } = parameters as WebSearchInput;
+
+    try {
+      const results = await this.webSearchService.search(
+        query,
+        { category, numResults },
+        {
+          workspaceId: context.workspaceId,
+          userWorkspaceId: context.userWorkspaceId,
+        },
+      );
+
+      return {
+        success: true,
+        message: `Found ${results.length} results for "${query}"${category ? ` (category: ${category})` : ''}`,
+        result: results,
+      };
+    } catch (error) {
+      return {
+        success: false,
+        message: `Web search failed for "${query}"`,
+        error: error instanceof Error ? error.message : 'Web search failed',
+      };
+    }
+  }
+}
@@ -19,6 +19,7 @@ import { SupportDriver } from 'src/engine/core-modules/twenty-config/interfaces/

 import { CaptchaDriverType } from 'src/engine/core-modules/captcha/interfaces';
 import { CodeInterpreterDriverType } from 'src/engine/core-modules/code-interpreter/code-interpreter.interface';
+import { WebSearchDriverType } from 'src/engine/core-modules/web-search/web-search.interface';
 import { EmailDriver } from 'src/engine/core-modules/email/enums/email-driver.enum';
 import { type AiModelPreferences } from 'src/engine/metadata-modules/ai/ai-models/types/ai-model-preferences.type';
 import { type AiProvidersConfig } from 'src/engine/metadata-modules/ai/ai-models/types/ai-providers-config.type';
@@ -661,6 +662,35 @@ export class ConfigVariables {
  @CastToPositiveNumber()
  CODE_INTERPRETER_TIMEOUT_MS = 300_000;

+  @ConfigVariablesMetadata({
+    group: ConfigVariablesGroup.LLM,
+    description:
+      'Web search driver type - EXA for Exa search, DISABLED to turn off',
+    type: ConfigVariableType.STRING,
+    options: Object.values(WebSearchDriverType),
+  })
+  @IsOptional()
+  @CastToUpperSnakeCase()
+  WEB_SEARCH_DRIVER: WebSearchDriverType = WebSearchDriverType.DISABLED;
+
+  @ConfigVariablesMetadata({
+    group: ConfigVariablesGroup.LLM,
+    description: 'Exa API key for web search',
+    type: ConfigVariableType.STRING,
+    isSensitive: true,
+  })
+  @ValidateIf((env) => env.WEB_SEARCH_DRIVER === WebSearchDriverType.EXA)
+  EXA_API_KEY?: string;
+
+  @ConfigVariablesMetadata({
+    group: ConfigVariablesGroup.LLM,
+    description:
+      'When true, use native provider search (Anthropic/OpenAI) when available. When false, always prefer the configured driver (e.g. Exa).',
+    type: ConfigVariableType.BOOLEAN,
+  })
+  @IsOptional()
+  WEB_SEARCH_PREFER_NATIVE = false;
+
  @ConfigVariablesMetadata({
    group: ConfigVariablesGroup.ANALYTICS_CONFIG,
    description: 'Enable or disable analytics for telemetry',
@@ -7,6 +7,7 @@ export enum UsageOperationType {
  AI_WORKFLOW_TOKEN = 'AI_WORKFLOW_TOKEN',
  WORKFLOW_EXECUTION = 'WORKFLOW_EXECUTION',
  CODE_EXECUTION = 'CODE_EXECUTION',
+  WEB_SEARCH = 'WEB_SEARCH',
 }

 registerEnumType(UsageOperationType, {
@@ -0,0 +1,9 @@
+export const WEB_SEARCH_CATEGORIES = [
+  'company',
+  'research paper',
+  'news',
+  'pdf',
+  'personal site',
+  'financial report',
+  'people',
+] as const;
@@ -0,0 +1,19 @@
+import {
+  type WebSearchCostModel,
+  type WebSearchDriver,
+} from 'src/engine/core-modules/web-search/drivers/interfaces/web-search-driver.interface';
+import { type WebSearchResult } from 'src/engine/core-modules/web-search/types/web-search-result.type';
+
+export class DisabledWebSearchDriver implements WebSearchDriver {
+  readonly costModel: WebSearchCostModel = {
+    baseResultCount: 0,
+    baseCostDollars: 0,
+    costPerAdditionalResultDollars: 0,
+  };
+
+  constructor(private readonly reason: string) {}
+
+  async search(): Promise<WebSearchResult[]> {
+    throw new Error(this.reason);
+  }
+}
@@ -0,0 +1,52 @@
+import Exa from 'exa-js';
+
+import {
+  type WebSearchCostModel,
+  type WebSearchDriver,
+} from 'src/engine/core-modules/web-search/drivers/interfaces/web-search-driver.interface';
+import { type WebSearchOptions } from 'src/engine/core-modules/web-search/types/web-search-options.type';
+import { type WebSearchResult } from 'src/engine/core-modules/web-search/types/web-search-result.type';
+
+const DEFAULT_NUM_RESULTS = 10;
+const MAX_HIGHLIGHT_CHARACTERS = 4000;
+
+// Exa charges $7/1k requests for auto search type (up to 10 results)
+// Additional results above 10 cost $1/1k = $0.001 each
+const EXA_BASE_COST_DOLLARS = 0.007;
+const EXA_COST_PER_ADDITIONAL_RESULT_DOLLARS = 0.001;
+
+export class ExaDriver implements WebSearchDriver {
+  readonly costModel: WebSearchCostModel = {
+    baseResultCount: DEFAULT_NUM_RESULTS,
+    baseCostDollars: EXA_BASE_COST_DOLLARS,
+    costPerAdditionalResultDollars: EXA_COST_PER_ADDITIONAL_RESULT_DOLLARS,
+  };
+
+  private readonly client: Exa;
+
+  constructor(apiKey: string) {
+    this.client = new Exa(apiKey);
+  }
+
+  async search(
+    query: string,
+    options?: WebSearchOptions,
+  ): Promise<WebSearchResult[]> {
+    const numResults = options?.numResults ?? DEFAULT_NUM_RESULTS;
+
+    const response = await this.client.search(query, {
+      type: 'auto',
+      numResults,
+      category: options?.category,
+      contents: {
+        highlights: { maxCharacters: MAX_HIGHLIGHT_CHARACTERS },
+      },
+    });
+
+    return response.results.map((result) => ({
+      title: result.title ?? '',
+      url: result.url,
+      snippet: result.highlights?.join('\n') ?? '',
+    }));
+  }
+}
@@ -0,0 +1,14 @@
+import { type WebSearchOptions } from 'src/engine/core-modules/web-search/types/web-search-options.type';
+import { type WebSearchResult } from 'src/engine/core-modules/web-search/types/web-search-result.type';
+
+export type WebSearchCostModel = {
+  baseResultCount: number;
+  baseCostDollars: number;
+  costPerAdditionalResultDollars: number;
+};
+
+export interface WebSearchDriver {
+  readonly costModel: WebSearchCostModel;
+
+  search(query: string, options?: WebSearchOptions): Promise<WebSearchResult[]>;
+}
@@ -0,0 +1,4 @@
+export type WebSearchBillingContext = {
+  workspaceId: string;
+  userWorkspaceId?: string;
+};
@@ -0,0 +1,3 @@
+import { type WEB_SEARCH_CATEGORIES } from 'src/engine/core-modules/web-search/constants/web-search-categories.const';
+
+export type WebSearchCategory = (typeof WEB_SEARCH_CATEGORIES)[number];
@@ -0,0 +1,6 @@
+import { type WebSearchCategory } from 'src/engine/core-modules/web-search/types/web-search-category.type';
+
+export type WebSearchOptions = {
+  category?: WebSearchCategory;
+  numResults?: number;
+};
@@ -0,0 +1,5 @@
+export type WebSearchResult = {
+  title: string;
+  url: string;
+  snippet: string;
+};
@@ -0,0 +1,55 @@
+import { Injectable } from '@nestjs/common';
+
+import { type WebSearchDriver } from 'src/engine/core-modules/web-search/drivers/interfaces/web-search-driver.interface';
+
+import { DisabledWebSearchDriver } from 'src/engine/core-modules/web-search/drivers/disabled.driver';
+import { ExaDriver } from 'src/engine/core-modules/web-search/drivers/exa.driver';
+import { WebSearchDriverType } from 'src/engine/core-modules/web-search/web-search.interface';
+import { DriverFactoryBase } from 'src/engine/core-modules/twenty-config/dynamic-factory.base';
+import { ConfigVariablesGroup } from 'src/engine/core-modules/twenty-config/enums/config-variables-group.enum';
+import { TwentyConfigService } from 'src/engine/core-modules/twenty-config/twenty-config.service';
+
+@Injectable()
+export class WebSearchDriverFactory extends DriverFactoryBase<WebSearchDriver> {
+  constructor(twentyConfigService: TwentyConfigService) {
+    super(twentyConfigService);
+  }
+
+  protected buildConfigKey(): string {
+    const driverType = this.twentyConfigService.get('WEB_SEARCH_DRIVER');
+
+    if (driverType !== WebSearchDriverType.DISABLED) {
+      return `${driverType}|${this.getConfigGroupHash(ConfigVariablesGroup.LLM)}`;
+    }
+
+    return driverType;
+  }
+
+  protected createDriver(): WebSearchDriver {
+    const driverType = this.twentyConfigService.get('WEB_SEARCH_DRIVER');
+
+    switch (driverType) {
+      case WebSearchDriverType.DISABLED:
+        return new DisabledWebSearchDriver(
+          'Web search is disabled. Set WEB_SEARCH_DRIVER to EXA and provide EXA_API_KEY to enable it.',
+        );
+
+      case WebSearchDriverType.EXA: {
+        const apiKey = this.twentyConfigService.get('EXA_API_KEY');
+
+        if (!apiKey) {
+          throw new Error(
+            'EXA_API_KEY is required when WEB_SEARCH_DRIVER is EXA',
+          );
+        }
+
+        return new ExaDriver(apiKey);
+      }
+
+      default:
+        throw new Error(
+          `Invalid web search driver type (${driverType}), check your .env file`,
+        );
+    }
+  }
+}
@@ -0,0 +1,4 @@
+export enum WebSearchDriverType {
+  EXA = 'EXA',
+  DISABLED = 'DISABLED',
+}
@@ -0,0 +1,17 @@
+import { type DynamicModule, Global } from '@nestjs/common';
+
+import { WebSearchDriverFactory } from 'src/engine/core-modules/web-search/web-search-driver.factory';
+import { WebSearchService } from 'src/engine/core-modules/web-search/web-search.service';
+import { TwentyConfigModule } from 'src/engine/core-modules/twenty-config/twenty-config.module';
+
+@Global()
+export class WebSearchModule {
+  static forRoot(): DynamicModule {
+    return {
+      module: WebSearchModule,
+      imports: [TwentyConfigModule],
+      providers: [WebSearchDriverFactory, WebSearchService],
+      exports: [WebSearchService],
+    };
+  }
+}
@@ -0,0 +1,102 @@
+import { Injectable } from '@nestjs/common';
+
+import {
+  type WebSearchCostModel,
+  type WebSearchDriver,
+} from 'src/engine/core-modules/web-search/drivers/interfaces/web-search-driver.interface';
+import { type WebSearchBillingContext } from 'src/engine/core-modules/web-search/types/web-search-billing-context.type';
+import { type WebSearchOptions } from 'src/engine/core-modules/web-search/types/web-search-options.type';
+import { type WebSearchResult } from 'src/engine/core-modules/web-search/types/web-search-result.type';
+import { WebSearchDriverFactory } from 'src/engine/core-modules/web-search/web-search-driver.factory';
+import { WebSearchDriverType } from 'src/engine/core-modules/web-search/web-search.interface';
+import { USAGE_RECORDED } from 'src/engine/core-modules/usage/constants/usage-recorded.constant';
+import { UsageOperationType } from 'src/engine/core-modules/usage/enums/usage-operation-type.enum';
+import { UsageResourceType } from 'src/engine/core-modules/usage/enums/usage-resource-type.enum';
+import { UsageUnit } from 'src/engine/core-modules/usage/enums/usage-unit.enum';
+import { type UsageEvent } from 'src/engine/core-modules/usage/types/usage-event.type';
+import { TwentyConfigService } from 'src/engine/core-modules/twenty-config/twenty-config.service';
+import { WorkspaceEventEmitter } from 'src/engine/workspace-event-emitter/workspace-event-emitter';
+import { DOLLAR_TO_CREDIT_MULTIPLIER } from 'src/engine/metadata-modules/ai/ai-billing/constants/dollar-to-credit-multiplier';
+
+@Injectable()
+export class WebSearchService {
+  constructor(
+    private readonly webSearchDriverFactory: WebSearchDriverFactory,
+    private readonly twentyConfigService: TwentyConfigService,
+    private readonly workspaceEventEmitter: WorkspaceEventEmitter,
+  ) {}
+
+  isEnabled(): boolean {
+    return (
+      this.twentyConfigService.get('WEB_SEARCH_DRIVER') !==
+      WebSearchDriverType.DISABLED
+    );
+  }
+
+  shouldUseNativeSearch(): boolean {
+    return (
+      this.twentyConfigService.get('WEB_SEARCH_PREFER_NATIVE') ||
+      !this.isEnabled()
+    );
+  }
+
+  async search(
+    query: string,
+    options?: WebSearchOptions,
+    billingContext?: WebSearchBillingContext,
+  ): Promise<WebSearchResult[]> {
+    const driver = this.webSearchDriverFactory.getCurrentDriver();
+    const results = await driver.search(query, options);
+
+    if (billingContext) {
+      this.emitUsageEvent(driver, results.length, billingContext);
+    }
+
+    return results;
+  }
+
+  static computeQueryCostDollars(
+    costModel: WebSearchCostModel,
+    numResults: number,
+  ): number {
+    const additionalResults = Math.max(
+      0,
+      numResults - costModel.baseResultCount,
+    );
+
+    return (
+      costModel.baseCostDollars +
+      additionalResults * costModel.costPerAdditionalResultDollars
+    );
+  }
+
+  private emitUsageEvent(
+    driver: WebSearchDriver,
+    numResults: number,
+    billingContext: WebSearchBillingContext,
+  ): void {
+    const costDollars = WebSearchService.computeQueryCostDollars(
+      driver.costModel,
+      numResults,
+    );
+    const creditsUsedMicro = Math.round(
+      costDollars * DOLLAR_TO_CREDIT_MULTIPLIER,
+    );
+
+    this.workspaceEventEmitter.emitCustomBatchEvent<UsageEvent>(
+      USAGE_RECORDED,
+      [
+        {
+          resourceType: UsageResourceType.AI,
+          operationType: UsageOperationType.WEB_SEARCH,
+          creditsUsedMicro,
+          quantity: 1,
+          unit: UsageUnit.INVOCATION,
+          resourceContext: this.twentyConfigService.get('WEB_SEARCH_DRIVER'),
+          userWorkspaceId: billingContext.userWorkspaceId ?? null,
+        },
+      ],
+      billingContext.workspaceId,
+    );
+  }
+}