🔍 feat: Anthropic/Google Web Search Support via addParams / dropParams (#10456)

* feat: add support for known/add/drop parameters in Anthropic and Google LLM configurations

* ci: add tests for web search support for Anthropic and Google configurations with addParams and dropParams handling

packages/api/src/endpoints/anthropic/llm.ts

@@ -4,6 +4,25 @@ import { anthropicSettings, removeNullishValues } from 'librechat-data-provider'
 import type { AnthropicLLMConfigResult, AnthropicConfigOptions } from '~/types/anthropic';
 import { checkPromptCacheSupport, getClaudeHeaders, configureReasoning } from './helpers';
 
+/** Known Anthropic parameters that map directly to the client config */
+export const knownAnthropicParams = new Set([
+  'model',
+  'temperature',
+  'topP',
+  'topK',
+  'maxTokens',
+  'maxOutputTokens',
+  'stopSequences',
+  'stop',
+  'stream',
+  'apiKey',
+  'maxRetries',
+  'timeout',
+  'anthropicVersion',
+  'anthropicApiUrl',
+  'defaultHeaders',
+]);
+
 /**
  * Generates configuration options for creating an Anthropic language model (LLM) instance.
  * @param apiKey - The API key for authentication with Anthropic.
@@ -39,6 +58,8 @@ function getLLMConfig(
 
   const mergedOptions = Object.assign(defaultOptions, options.modelOptions);
 
+  let enableWebSearch = mergedOptions.web_search;
+
   let requestOptions: AnthropicClientOptions & { stream?: boolean } = {
     apiKey,
     model: mergedOptions.model,
@@ -84,9 +105,45 @@ function getLLMConfig(
     requestOptions.anthropicApiUrl = options.reverseProxyUrl;
   }
 
+  /** Handle addParams - only process Anthropic-native params, leave OpenAI params for transform */
+  if (options.addParams && typeof options.addParams === 'object') {
+    for (const [key, value] of Object.entries(options.addParams)) {
+      /** Handle web_search separately - don't add to config */
+      if (key === 'web_search') {
+        if (typeof value === 'boolean') {
+          enableWebSearch = value;
+        }
+        continue;
+      }
+
+      if (knownAnthropicParams.has(key)) {
+        /** Route known Anthropic params to requestOptions */
+        (requestOptions as Record<string, unknown>)[key] = value;
+      }
+      /** Leave other params for transform to handle - they might be OpenAI params */
+    }
+  }
+
+  /** Handle dropParams - only drop from Anthropic config */
+  if (options.dropParams && Array.isArray(options.dropParams)) {
+    options.dropParams.forEach((param) => {
+      if (param === 'web_search') {
+        enableWebSearch = false;
+        return;
+      }
+
+      if (param in requestOptions) {
+        delete requestOptions[param as keyof AnthropicClientOptions];
+      }
+      if (requestOptions.invocationKwargs && param in requestOptions.invocationKwargs) {
+        delete (requestOptions.invocationKwargs as Record<string, unknown>)[param];
+      }
+    });
+  }
+
   const tools = [];
 
-  if (mergedOptions.web_search) {
+  if (enableWebSearch) {
     tools.push({
       type: 'web_search_20250305',
       name: 'web_search',

packages/api/src/endpoints/google/llm.ts

@@ -5,6 +5,33 @@ import type { GoogleAIToolType } from '@langchain/google-common';
 import type * as t from '~/types';
 import { isEnabled } from '~/utils';
 
+/** Known Google/Vertex AI parameters that map directly to the client config */
+export const knownGoogleParams = new Set([
+  'model',
+  'modelName',
+  'temperature',
+  'maxOutputTokens',
+  'maxReasoningTokens',
+  'topP',
+  'topK',
+  'seed',
+  'presencePenalty',
+  'frequencyPenalty',
+  'stopSequences',
+  'stop',
+  'logprobs',
+  'topLogprobs',
+  'safetySettings',
+  'responseModalities',
+  'convertSystemMessageToHumanContent',
+  'speechConfig',
+  'streamUsage',
+  'apiKey',
+  'baseUrl',
+  'location',
+  'authOptions',
+]);
+
 function getThresholdMapping(model: string) {
   const gemini1Pattern = /gemini-(1\.0|1\.5|pro$|1\.0-pro|1\.5-pro|1\.5-flash-001)/;
   const restrictedPattern = /(gemini-(1\.5-flash-8b|2\.0|exp)|learnlm)/;
@@ -112,6 +139,8 @@ export function getGoogleConfig(
     ...modelOptions
   } = options.modelOptions || {};
 
+  let enableWebSearch = web_search;
+
   const llmConfig: GoogleClientOptions | VertexAIClientOptions = removeNullishValues({
     ...(modelOptions || {}),
     model: modelOptions?.model ?? '',
@@ -193,9 +222,42 @@ export function getGoogleConfig(
     };
   }
 
+  /** Handle addParams - only process Google-native params, leave OpenAI params for transform */
+  if (options.addParams && typeof options.addParams === 'object') {
+    for (const [key, value] of Object.entries(options.addParams)) {
+      /** Handle web_search separately - don't add to config */
+      if (key === 'web_search') {
+        if (typeof value === 'boolean') {
+          enableWebSearch = value;
+        }
+        continue;
+      }
+
+      if (knownGoogleParams.has(key)) {
+        /** Route known Google params to llmConfig */
+        (llmConfig as Record<string, unknown>)[key] = value;
+      }
+      /** Leave other params for transform to handle - they might be OpenAI params */
+    }
+  }
+
+  /** Handle dropParams - only drop from Google config */
+  if (options.dropParams && Array.isArray(options.dropParams)) {
+    options.dropParams.forEach((param) => {
+      if (param === 'web_search') {
+        enableWebSearch = false;
+        return;
+      }
+
+      if (param in llmConfig) {
+        delete (llmConfig as Record<string, unknown>)[param];
+      }
+    });
+  }
+
   const tools: GoogleAIToolType[] = [];
 
-  if (web_search) {
+  if (enableWebSearch) {
     tools.push({ googleSearch: {} });
   }
 

packages/api/src/endpoints/openai/config.anthropic.spec.ts

@@ -548,4 +548,139 @@ describe('getOpenAIConfig - Anthropic Compatibility', () => {
       });
     });
   });
+
+  describe('Web Search Support via addParams', () => {
+    it('should enable web_search tool when web_search: true in addParams', () => {
+      const apiKey = 'sk-web-search';
+      const endpoint = 'Anthropic (Custom)';
+      const options = {
+        modelOptions: {
+          model: 'claude-3-5-sonnet-latest',
+          user: 'search-user',
+        },
+        customParams: {
+          defaultParamsEndpoint: 'anthropic',
+        },
+        addParams: {
+          web_search: true,
+        },
+      };
+
+      const result = getOpenAIConfig(apiKey, options, endpoint);
+
+      expect(result.tools).toEqual([
+        {
+          type: 'web_search_20250305',
+          name: 'web_search',
+        },
+      ]);
+      expect(result.llmConfig).toMatchObject({
+        model: 'claude-3-5-sonnet-latest',
+        stream: true,
+      });
+    });
+
+    it('should disable web_search tool when web_search: false in addParams', () => {
+      const apiKey = 'sk-no-search';
+      const endpoint = 'Anthropic (Custom)';
+      const options = {
+        modelOptions: {
+          model: 'claude-3-opus-20240229',
+          web_search: true, // This should be overridden by addParams
+        },
+        customParams: {
+          defaultParamsEndpoint: 'anthropic',
+        },
+        addParams: {
+          web_search: false,
+        },
+      };
+
+      const result = getOpenAIConfig(apiKey, options, endpoint);
+
+      expect(result.tools).toEqual([]);
+    });
+
+    it('should disable web_search when in dropParams', () => {
+      const apiKey = 'sk-drop-search';
+      const endpoint = 'Anthropic (Custom)';
+      const options = {
+        modelOptions: {
+          model: 'claude-3-5-sonnet-latest',
+          web_search: true,
+        },
+        customParams: {
+          defaultParamsEndpoint: 'anthropic',
+        },
+        dropParams: ['web_search'],
+      };
+
+      const result = getOpenAIConfig(apiKey, options, endpoint);
+
+      expect(result.tools).toEqual([]);
+    });
+
+    it('should handle web_search with mixed Anthropic and OpenAI params in addParams', () => {
+      const apiKey = 'sk-mixed';
+      const endpoint = 'Anthropic (Custom)';
+      const options = {
+        modelOptions: {
+          model: 'claude-3-opus-20240229',
+          user: 'mixed-user',
+        },
+        customParams: {
+          defaultParamsEndpoint: 'anthropic',
+        },
+        addParams: {
+          web_search: true,
+          temperature: 0.7, // Anthropic native
+          maxRetries: 3, // OpenAI param (known), should go to top level
+          customParam: 'custom', // Unknown param, should go to modelKwargs
+        },
+      };
+
+      const result = getOpenAIConfig(apiKey, options, endpoint);
+
+      expect(result.tools).toEqual([
+        {
+          type: 'web_search_20250305',
+          name: 'web_search',
+        },
+      ]);
+      expect(result.llmConfig.temperature).toBe(0.7);
+      expect(result.llmConfig.maxRetries).toBe(3); // Known OpenAI param at top level
+      expect(result.llmConfig.modelKwargs).toMatchObject({
+        customParam: 'custom', // Unknown param in modelKwargs
+        metadata: { user_id: 'mixed-user' }, // From invocationKwargs
+      });
+    });
+
+    it('should handle Anthropic native params in addParams without web_search', () => {
+      const apiKey = 'sk-native';
+      const endpoint = 'Anthropic (Custom)';
+      const options = {
+        modelOptions: {
+          model: 'claude-3-opus-20240229',
+        },
+        customParams: {
+          defaultParamsEndpoint: 'anthropic',
+        },
+        addParams: {
+          temperature: 0.9,
+          topP: 0.95,
+          maxTokens: 4096,
+        },
+      };
+
+      const result = getOpenAIConfig(apiKey, options, endpoint);
+
+      expect(result.llmConfig).toMatchObject({
+        model: 'claude-3-opus-20240229',
+        temperature: 0.9,
+        topP: 0.95,
+        maxTokens: 4096,
+      });
+      expect(result.tools).toEqual([]);
+    });
+  });
 });

packages/api/src/endpoints/openai/config.google.spec.ts

@@ -0,0 +1,196 @@
+import { getOpenAIConfig } from './config';
+
+describe('getOpenAIConfig - Google Compatibility', () => {
+  describe('Google via Custom Endpoint', () => {
+    describe('Web Search Support via addParams', () => {
+      it('should enable googleSearch tool when web_search: true in addParams', () => {
+        const apiKey = JSON.stringify({ GOOGLE_API_KEY: 'test-google-key' });
+        const endpoint = 'Gemini (Custom)';
+        const options = {
+          modelOptions: {
+            model: 'gemini-2.0-flash-exp',
+          },
+          customParams: {
+            defaultParamsEndpoint: 'google',
+          },
+          addParams: {
+            web_search: true,
+          },
+          reverseProxyUrl: 'https://generativelanguage.googleapis.com/v1beta/openai',
+        };
+
+        const result = getOpenAIConfig(apiKey, options, endpoint);
+
+        expect(result.tools).toEqual([{ googleSearch: {} }]);
+        expect(result.llmConfig).toMatchObject({
+          model: 'gemini-2.0-flash-exp',
+        });
+      });
+
+      it('should disable googleSearch tool when web_search: false in addParams', () => {
+        const apiKey = JSON.stringify({ GOOGLE_API_KEY: 'test-google-key' });
+        const endpoint = 'Gemini (Custom)';
+        const options = {
+          modelOptions: {
+            model: 'gemini-2.0-flash-exp',
+            web_search: true, // Should be overridden by addParams
+          },
+          customParams: {
+            defaultParamsEndpoint: 'google',
+          },
+          addParams: {
+            web_search: false,
+          },
+          reverseProxyUrl: 'https://generativelanguage.googleapis.com/v1beta/openai',
+        };
+
+        const result = getOpenAIConfig(apiKey, options, endpoint);
+
+        expect(result.tools).toEqual([]);
+      });
+
+      it('should disable googleSearch when in dropParams', () => {
+        const apiKey = JSON.stringify({ GOOGLE_API_KEY: 'test-google-key' });
+        const endpoint = 'Gemini (Custom)';
+        const options = {
+          modelOptions: {
+            model: 'gemini-2.0-flash-exp',
+            web_search: true,
+          },
+          customParams: {
+            defaultParamsEndpoint: 'google',
+          },
+          dropParams: ['web_search'],
+          reverseProxyUrl: 'https://generativelanguage.googleapis.com/v1beta/openai',
+        };
+
+        const result = getOpenAIConfig(apiKey, options, endpoint);
+
+        expect(result.tools).toEqual([]);
+      });
+
+      it('should handle web_search with mixed Google and OpenAI params in addParams', () => {
+        const apiKey = JSON.stringify({ GOOGLE_API_KEY: 'test-google-key' });
+        const endpoint = 'Gemini (Custom)';
+        const options = {
+          modelOptions: {
+            model: 'gemini-2.0-flash-exp',
+          },
+          customParams: {
+            defaultParamsEndpoint: 'google',
+          },
+          addParams: {
+            web_search: true,
+            temperature: 0.8, // Shared param (both Google and OpenAI)
+            topK: 40, // Google-only param, goes to modelKwargs
+            frequencyPenalty: 0.5, // Known OpenAI param, goes to top level
+            customUnknown: 'test', // Unknown param, goes to modelKwargs
+          },
+          reverseProxyUrl: 'https://generativelanguage.googleapis.com/v1beta/openai',
+        };
+
+        const result = getOpenAIConfig(apiKey, options, endpoint);
+
+        expect(result.tools).toEqual([{ googleSearch: {} }]);
+        expect(result.llmConfig.temperature).toBe(0.8); // Shared param at top level
+        expect(result.llmConfig.frequencyPenalty).toBe(0.5); // Known OpenAI param at top level
+        expect(result.llmConfig.modelKwargs).toMatchObject({
+          topK: 40, // Google-specific in modelKwargs
+          customUnknown: 'test', // Unknown param in modelKwargs
+        });
+      });
+
+      it('should handle Google native params in addParams without web_search', () => {
+        const apiKey = JSON.stringify({ GOOGLE_API_KEY: 'test-google-key' });
+        const endpoint = 'Gemini (Custom)';
+        const options = {
+          modelOptions: {
+            model: 'gemini-2.0-flash-exp',
+          },
+          customParams: {
+            defaultParamsEndpoint: 'google',
+          },
+          addParams: {
+            temperature: 0.9, // Shared param (both Google and OpenAI)
+            topP: 0.95, // Shared param (both Google and OpenAI)
+            topK: 50, // Google-only, goes to modelKwargs
+            maxOutputTokens: 8192, // Google-only, goes to modelKwargs
+          },
+          reverseProxyUrl: 'https://generativelanguage.googleapis.com/v1beta/openai',
+        };
+
+        const result = getOpenAIConfig(apiKey, options, endpoint);
+
+        expect(result.llmConfig).toMatchObject({
+          model: 'gemini-2.0-flash-exp',
+          temperature: 0.9, // Shared params at top level
+          topP: 0.95,
+        });
+        expect(result.llmConfig.modelKwargs).toMatchObject({
+          topK: 50, // Google-specific in modelKwargs
+          maxOutputTokens: 8192,
+        });
+        expect(result.tools).toEqual([]);
+      });
+
+      it('should drop Google native params with dropParams', () => {
+        const apiKey = JSON.stringify({ GOOGLE_API_KEY: 'test-google-key' });
+        const endpoint = 'Gemini (Custom)';
+        const options = {
+          modelOptions: {
+            model: 'gemini-2.0-flash-exp',
+            temperature: 0.7,
+            topK: 40,
+            topP: 0.9,
+          },
+          customParams: {
+            defaultParamsEndpoint: 'google',
+          },
+          dropParams: ['topK', 'topP'],
+          reverseProxyUrl: 'https://generativelanguage.googleapis.com/v1beta/openai',
+        };
+
+        const result = getOpenAIConfig(apiKey, options, endpoint);
+
+        expect(result.llmConfig.temperature).toBe(0.7);
+        expect((result.llmConfig as Record<string, unknown>).topK).toBeUndefined();
+        expect(result.llmConfig.topP).toBeUndefined();
+      });
+
+      it('should handle both addParams and dropParams for Google', () => {
+        const apiKey = JSON.stringify({ GOOGLE_API_KEY: 'test-google-key' });
+        const endpoint = 'Gemini (Custom)';
+        const options = {
+          modelOptions: {
+            model: 'gemini-2.0-flash-exp',
+            topK: 30, // Will be dropped
+          },
+          customParams: {
+            defaultParamsEndpoint: 'google',
+          },
+          addParams: {
+            web_search: true,
+            temperature: 0.8, // Shared param
+            maxOutputTokens: 4096, // Google-only param
+          },
+          dropParams: ['topK'],
+          reverseProxyUrl: 'https://generativelanguage.googleapis.com/v1beta/openai',
+        };
+
+        const result = getOpenAIConfig(apiKey, options, endpoint);
+
+        expect(result.tools).toEqual([{ googleSearch: {} }]);
+        expect(result.llmConfig).toMatchObject({
+          model: 'gemini-2.0-flash-exp',
+          temperature: 0.8,
+        });
+        expect(result.llmConfig.modelKwargs).toMatchObject({
+          maxOutputTokens: 4096, // Google-specific in modelKwargs
+        });
+        expect((result.llmConfig as Record<string, unknown>).topK).toBeUndefined();
+        // Verify topK is not in modelKwargs either
+        expect(result.llmConfig.modelKwargs?.topK).toBeUndefined();
+      });
+    });
+  });
+});

packages/api/src/endpoints/openai/config.ts

@@ -3,6 +3,7 @@ import { Providers } from '@librechat/agents';
 import { KnownEndpoints, EModelEndpoint } from 'librechat-data-provider';
 import type * as t from '~/types';
 import { getLLMConfig as getAnthropicLLMConfig } from '~/endpoints/anthropic/llm';
+import { getGoogleConfig } from '~/endpoints/google/llm';
 import { transformToOpenAIConfig } from './transform';
 import { constructAzureURL } from '~/utils/azure';
 import { createFetch } from '~/utils/generators';
@@ -36,14 +37,18 @@ export function getOpenAIConfig(
   let llmConfig: t.OAIClientOptions;
   let tools: t.LLMConfigResult['tools'];
   const isAnthropic = options.customParams?.defaultParamsEndpoint === EModelEndpoint.anthropic;
+  const isGoogle = options.customParams?.defaultParamsEndpoint === EModelEndpoint.google;
 
   const useOpenRouter =
     !isAnthropic &&
+    !isGoogle &&
     ((baseURL && baseURL.includes(KnownEndpoints.openrouter)) ||
       (endpoint != null && endpoint.toLowerCase().includes(KnownEndpoints.openrouter)));
   const isVercel =
-    (baseURL && baseURL.includes('ai-gateway.vercel.sh')) ||
-    (endpoint != null && endpoint.toLowerCase().includes(KnownEndpoints.vercel));
+    !isAnthropic &&
+    !isGoogle &&
+    ((baseURL && baseURL.includes('ai-gateway.vercel.sh')) ||
+      (endpoint != null && endpoint.toLowerCase().includes(KnownEndpoints.vercel)));
 
   let azure = options.azure;
   let headers = options.headers;
@@ -51,7 +56,11 @@ export function getOpenAIConfig(
     const anthropicResult = getAnthropicLLMConfig(apiKey, {
       modelOptions,
       proxy: options.proxy,
+      reverseProxyUrl: baseURL,
+      addParams,
+      dropParams,
     });
+    /** Transform handles addParams/dropParams - it knows about OpenAI params */
     const transformed = transformToOpenAIConfig({
       addParams,
       dropParams,
@@ -63,6 +72,23 @@ export function getOpenAIConfig(
     if (transformed.configOptions?.defaultHeaders) {
       headers = Object.assign(headers ?? {}, transformed.configOptions?.defaultHeaders);
     }
+  } else if (isGoogle) {
+    const googleResult = getGoogleConfig(apiKey, {
+      modelOptions,
+      reverseProxyUrl: baseURL ?? undefined,
+      authHeader: true,
+      addParams,
+      dropParams,
+    });
+    /** Transform handles addParams/dropParams - it knows about OpenAI params */
+    const transformed = transformToOpenAIConfig({
+      addParams,
+      dropParams,
+      llmConfig: googleResult.llmConfig,
+      fromEndpoint: EModelEndpoint.google,
+    });
+    llmConfig = transformed.llmConfig;
+    tools = googleResult.tools;
   } else {
     const openaiResult = getOpenAILLMConfig({
       azure,

packages/api/src/endpoints/openai/transform.ts

@@ -4,6 +4,7 @@ import type * as t from '~/types';
 import { knownOpenAIParams } from './llm';
 
 const anthropicExcludeParams = new Set(['anthropicApiUrl']);
+const googleExcludeParams = new Set(['safetySettings', 'location', 'baseUrl', 'customHeaders']);
 
 /**
  * Transforms a Non-OpenAI LLM config to an OpenAI-conformant config.
@@ -31,7 +32,14 @@ export function transformToOpenAIConfig({
   let hasModelKwargs = false;
 
   const isAnthropic = fromEndpoint === EModelEndpoint.anthropic;
-  const excludeParams = isAnthropic ? anthropicExcludeParams : new Set();
+  const isGoogle = fromEndpoint === EModelEndpoint.google;
+
+  let excludeParams = new Set<string>();
+  if (isAnthropic) {
+    excludeParams = anthropicExcludeParams;
+  } else if (isGoogle) {
+    excludeParams = googleExcludeParams;
+  }
 
   for (const [key, value] of Object.entries(llmConfig)) {
     if (value === undefined || value === null) {
@@ -49,6 +57,19 @@ export function transformToOpenAIConfig({
       modelKwargs = Object.assign({}, modelKwargs, value as Record<string, unknown>);
       hasModelKwargs = true;
       continue;
+    } else if (isGoogle && key === 'authOptions') {
+      // Handle Google authOptions
+      modelKwargs = Object.assign({}, modelKwargs, value as Record<string, unknown>);
+      hasModelKwargs = true;
+      continue;
+    } else if (
+      isGoogle &&
+      (key === 'thinkingConfig' || key === 'thinkingBudget' || key === 'includeThoughts')
+    ) {
+      // Handle Google thinking configuration
+      modelKwargs = Object.assign({}, modelKwargs, { [key]: value });
+      hasModelKwargs = true;
+      continue;
     }
 
     if (knownOpenAIParams.has(key)) {
@@ -61,6 +82,11 @@ export function transformToOpenAIConfig({
 
   if (addParams && typeof addParams === 'object') {
     for (const [key, value] of Object.entries(addParams)) {
+      /** Skip web_search - it's handled separately as a tool */
+      if (key === 'web_search') {
+        continue;
+      }
+
       if (knownOpenAIParams.has(key)) {
         (openAIConfig as Record<string, unknown>)[key] = value;
       } else {
@@ -76,16 +102,23 @@ export function transformToOpenAIConfig({
 
   if (dropParams && Array.isArray(dropParams)) {
     dropParams.forEach((param) => {
+      /** Skip web_search - handled separately */
+      if (param === 'web_search') {
+        return;
+      }
+
       if (param in openAIConfig) {
         delete openAIConfig[param as keyof t.OAIClientOptions];
       }
       if (openAIConfig.modelKwargs && param in openAIConfig.modelKwargs) {
         delete openAIConfig.modelKwargs[param];
-        if (Object.keys(openAIConfig.modelKwargs).length === 0) {
-          delete openAIConfig.modelKwargs;
-        }
       }
     });
+
+    /** Clean up empty modelKwargs after dropParams processing */
+    if (openAIConfig.modelKwargs && Object.keys(openAIConfig.modelKwargs).length === 0) {
+      delete openAIConfig.modelKwargs;
+    }
   }
 
   return {

packages/api/src/types/anthropic.ts

@@ -54,6 +54,10 @@ export interface AnthropicConfigOptions {
   proxy?: string | null;
   /** URL for a reverse proxy, if used */
   reverseProxyUrl?: string | null;
+  /** Additional parameters to add to the configuration */
+  addParams?: Record<string, unknown>;
+  /** Parameters to drop/exclude from the configuration */
+  dropParams?: string[];
 }
 
 /**