Auto-respond to Gmail enquiries using GPT-4o, Dumpling AI & LangChain agent
Needs changesNeeds changes. This template uses 2 thing(s) that n8n 3.0 removes: HTTP Request Tool (legacy), AI Agent v1 (old agent modes). 2 breaking item(s) found. Static check, last run 2026-10-19.
What this workflow does
This AI workflow has 8 nodes and runs on Gmail events. Along the way it connects Gmail, OpenAI, OpenAI Chat Model and HTTP Request. It also calls app.dumplingai.com over HTTP.
How it runs
Trigger: On Gmail events.
- Classify Email Type with GPT-4o (OpenAI): uses OpenAI
- Only Proceed if Email is an Enquiry (Filter): keeps only the items that match a condition
- LangChain Agent Handles Reply Logic (AI Agent): runs an AI agent, with model: GPT-4o Chat Model; 2 tools (Send Email Response via Gmail, Dumpling AI Agent – Search for Relevant Info); memory: Memory Buffer (Past 10 Interactions)
Services it uses
HTTP calls to: app.dumplingai.com
Before you upgrade to n8n 3.0
2 things in this workflow are removed in n8n 3.0. Fix them before you upgrade:
- HTTP Request Tool (legacy) in Dumpling AI Agent – Search for Relevant Info: replace with HTTP Request node connected to the AI Agent's Tool input.
- AI Agent v1 (old agent modes) in LangChain Agent Handles Reply Logic (v1.8): replace with Latest AI Agent node (Tools Agent). For SQL Agent, use a Postgres or MySQL tool with a recent AI Agent.
- Also check Gmail Trigger below v1.4 runs as v1.4 (drafts skipped, max emails per poll).
Rather not rewrite it? Many of these flows can be rebuilt in Make (free plan).
| Removed in 3.0 | Replace with |
|---|---|
| HTTP Request Tool (legacy) Dumpling AI Agent – Search for Relevant Info | HTTP Request node connected to the AI Agent's Tool input |
| AI Agent v1 (old agent modes) LangChain Agent Handles Reply Logic (v1.8) | Latest AI Agent node (Tools Agent). For SQL Agent, use a Postgres or MySQL tool with a recent AI Agent. |
Nodes used (8)
- Gmail Trigger
n8n-nodes-base.gmailTrigger - OpenAI
@n8n/n8n-nodes-langchain.openAi - Filter
n8n-nodes-base.filter - OpenAI Chat Model
@n8n/n8n-nodes-langchain.lmChatOpenAi - Simple Memory
@n8n/n8n-nodes-langchain.memoryBufferWindow - HTTP Request Tool
@n8n/n8n-nodes-langchain.toolHttpRequest - Gmail Tool
n8n-nodes-base.gmailTool - AI Agent
@n8n/n8n-nodes-langchain.agent
From the author
Who is this for? This workflow is perfect for customer support teams, sales departments, or solopreneurs who receive frequent email enquiries and want to automate the initial response process using AI. If you spend too much time answering similar questions,…