Task: AI chatbot that can search the web

n8n workflow JSON:
{"meta":{"instanceId":"408f9fb9940c3cb18ffdef0e0150fe342d6e655c3a9fac21f0f644e8bedabcd9","templateCredsSetupCompleted":true},"nodes":[{"id":"a8211c61-5ca5-4b0a-adce-b7954a387aba","name":"Sticky Note4","type":"n8n-nodes-base.stickyNote","position":[-540,900],"parameters":{"width":300,"height":225,"content":"### The conversation history (last 20 messages) is stored in a buffer memory"},"typeVersion":1},{"id":"639ef27d-3e6e-4d2b-804a-5d1c95d509fc","name":"Sticky Note3","type":"n8n-nodes-base.stickyNote","position":[-200,900],"parameters":{"width":340,"height":225,"content":"### Tools which agent can use to accomplish the task"},"typeVersion":1},{"id":"dcb7ade3-005c-44e3-a369-526baa5b8813","name":"Sticky Note6","type":"n8n-nodes-base.stickyNote","position":[-500,500],"parameters":{"width":422,"height":211,"content":"### Conversational agent will utilise available tools to answer the prompt. "},"typeVersion":1},{"id":"2830de15-bdd2-48f4-8957-659014cd0a82","name":"When chat message received","type":"@n8n/n8n-nodes-langchain.chatTrigger","position":[-800,580],"webhookId":"d48f9e07-3c05-4be8-86ca-5cee4c27b78f","parameters":{"options":{}},"typeVersion":1.1},{"id":"bd1865fc-c37f-4b81-8ee1-83205e67e42b","name":"OpenAI Chat Model","type":"@n8n/n8n-nodes-langchain.lmChatOpenAi","position":[-720,1000],"parameters":{"model":{"__rl":true,"mode":"list","value":"gpt-4o-mini"},"options":{}},"credentials":{"openAiApi":{"id":"8gccIjcuf3gvaoEr","name":"OpenAi account"}},"typeVersion":1.2},{"id":"d9ee6da6-f2cd-4077-913c-9215433dfc31","name":"Simple Memory","type":"@n8n/n8n-nodes-langchain.memoryBufferWindow","position":[-440,1000],"parameters":{"contextWindowLength":20},"typeVersion":1.3},{"id":"fe8ddba3-37ba-43c3-9797-021b14a1be49","name":"SerpAPI","type":"@n8n/n8n-nodes-langchain.toolSerpApi","position":[-140,1000],"parameters":{"options":{}},"credentials":{"serpApi":{"id":"aJCKjxx6U3K7ydDe","name":"SerpAPI account"}},"typeVersion":1},{"id":"f7cee7ea-6a21-4eae-a1c6-36716683a3eb","name":"Wikipedia","type":"@n8n/n8n-nodes-langchain.toolWikipedia","position":[0,1000],"parameters":{},"typeVersion":1},{"id":"e6f6fe48-3ad0-4bfe-a2f2-922e4c652306","name":"AI Agent","type":"@n8n/n8n-nodes-langchain.agent","position":[-420,580],"parameters":{"options":{}},"typeVersion":1.8}],"pinData":{},"connections":{"SerpAPI":{"ai_tool":[[{"node":"AI Agent","type":"ai_tool","index":0}]]},"Wikipedia":{"ai_tool":[[{"node":"AI Agent","type":"ai_tool","index":0}]]},"Simple Memory":{"ai_memory":[[{"node":"AI Agent","type":"ai_memory","index":0}]]},"OpenAI Chat Model":{"ai_languageModel":[[{"node":"AI Agent","type":"ai_languageModel","index":0}]]},"When chat message received":{"main":[[{"node":"AI Agent","type":"main","index":0}]]}}}