feat: support sonnet 4.5 (#2938)

Author: Kitenite

packages/ai/src/agents/classes/root.ts

@@ -1,6 +1,6 @@
-import { BaseAgent } from '../models/base';
-import { getAskModeSystemPrompt, getCreatePageSystemPrompt, getSystemPrompt, initModel, UserAgentTool } from '../../index';
 import { AgentType, ChatType, LLMProvider, OPENROUTER_MODELS, type ModelConfig } from '@onlook/models';
+import { getAskModeSystemPrompt, getCreatePageSystemPrompt, getSystemPrompt, initModel } from '../../index';
+import { BaseAgent } from '../models/base';
 import { readOnlyRootTools, rootTools } from '../tool-lookup';
 
 export function getToolFromType(chatType: ChatType) {
@@ -51,7 +51,7 @@ export class RootAgent extends BaseAgent {
             default:
                 return initModel({
                     provider: LLMProvider.OPENROUTER,
-                    model: OPENROUTER_MODELS.CLAUDE_4_SONNET,
+                    model: OPENROUTER_MODELS.CLAUDE_4_5_SONNET,
                 });
         }
     }

packages/ai/src/chat/providers.ts

@@ -33,7 +33,7 @@ export function initModel({
             providerOptions = {
                 openrouter: { transforms: ['middle-out'] },
             };
-            const isClaude = requestedModel === OPENROUTER_MODELS.CLAUDE_4_SONNET;
+            const isClaude = requestedModel === OPENROUTER_MODELS.CLAUDE_4_SONNET || requestedModel === OPENROUTER_MODELS.CLAUDE_4_5_SONNET || requestedModel === OPENROUTER_MODELS.CLAUDE_3_5_HAIKU;
             providerOptions = isClaude
                 ? { ...providerOptions, anthropic: { cacheControl: { type: 'ephemeral' } } }
                 : providerOptions;

packages/models/src/llm/index.ts

@@ -12,6 +12,7 @@ export enum ANTHROPIC_MODELS {
 
 export enum OPENROUTER_MODELS {
     // Generate object does not work for Anthropic models https://github.com/OpenRouterTeam/ai-sdk-provider/issues/165
+    CLAUDE_4_5_SONNET = 'anthropic/claude-sonnet-4.5',
     CLAUDE_4_SONNET = 'anthropic/claude-sonnet-4',
     CLAUDE_3_5_HAIKU = 'anthropic/claude-3.5-haiku',
     OPEN_AI_GPT_5 = 'openai/gpt-5',
@@ -39,6 +40,7 @@ export type ModelConfig = {
 };
 
 export const MODEL_MAX_TOKENS = {
+    [OPENROUTER_MODELS.CLAUDE_4_5_SONNET]: 200000,
     [OPENROUTER_MODELS.CLAUDE_4_SONNET]: 200000,
     [OPENROUTER_MODELS.CLAUDE_3_5_HAIKU]: 200000,
     [OPENROUTER_MODELS.OPEN_AI_GPT_5_NANO]: 400000,