This article provides a complete, practical walkthrough of the Gmail Googlecalendartool Send Triggered n8n agent. It connects HTTP Request, Webhook across approximately 1 node(s). Expect a Intermediate setup in 15-45 minutes. One‑time purchase: €29.

What This Agent Does

This agent orchestrates a reliable automation between HTTP Request, Webhook, handling triggers, data enrichment, and delivery with guardrails for errors and rate limits.

It streamlines multi‑step processes that would otherwise require manual exports, spreadsheet cleanup, and repeated API requests. By centralizing logic in n8n, it reduces context switching, lowers error rates, and ensures consistent results across teams.

Typical outcomes include faster lead handoffs, automated notifications, accurate data synchronization, and better visibility via execution logs and optional Slack/Email alerts.

How It Works

The workflow uses standard n8n building blocks like Webhook or Schedule triggers, HTTP Request for API calls, and control nodes (IF, Merge, Set) to validate inputs, branch on conditions, and format outputs. Retries and timeouts improve resilience, while credentials keep secrets safe.

Third‑Party Integrations

• HTTP Request
• Webhook

Import and Use in n8n

1. Open n8n and create a new workflow or collection.
2. Choose Import from File or Paste JSON.
3. Paste the JSON below, then click Import.
4. Show n8n JSON

   Title:  
   Automated Email Scheduling Assistant Using n8n, GPT-4, and Google Calendar  
   
   Meta Description:  
   Discover how to build a smart AI-powered email assistant using n8n, OpenAI's GPT-4, Gmail, and Google Calendar. Automate appointment detection, check schedule availability, and reply to emails — hands-free!
   
   Keywords:
   - n8n workflow
   - AI email assistant
   - Gmail automation
   - GPT-4 email processing
   - AI scheduling assistant
   - Google Calendar automation
   - appointment email responder
   - intelligent email parsing
   - OpenAI GPT integration
   - smart email replies
   
   Third-Party APIs Used:
   - OpenAI API (GPT-4o-mini)
   - Gmail API (Gmail Trigger, Gmail Send, Mark as Read)
   - Google Calendar API
   
   Article:
   
   Automate Appointment Requests with an AI-Powered Email Assistant Using n8n
   
   In a world where digital communication often dictates your schedule, managing appointment requests efficiently is essential. Whether you're a solopreneur, executive assistant, or just someone tired of switching between emails and calendars, automation can lift a heavy weight off your shoulders.
   
   In this article, we'll walk through an n8n workflow that uses AI—specifically OpenAI’s GPT-4o-mini—and Google tools to intelligently identify appointment-related emails and automatically respond based on your calendar availability.
   
   Let’s break down how this automation works and dive into the components that make it possible.
   
   Summary of How the Workflow Functions:
   
   This n8n workflow acts as an intelligent email scheduling assistant. It performs the following steps:
   
   1. Detects unread emails in your Gmail inbox.
   2. Uses GPT-4 to determine if the email is requesting an appointment.
   3. If it is, it checks your Google Calendar for availability.
   4. Composes a human-like response with proposed meeting times.
   5. Sends a reply via Gmail.
   6. Marks the email as read to avoid reprocessing.
   
   Sounds like magic? Let's look at how each part works.
   
   Step 1: Gmail Trigger — Monitoring Inbox for New Emails
   
   At the forefront of this workflow is the Gmail Trigger node. It actively watches your Gmail inbox for unread emails, polling every minute to ensure timeliness. This node retrieves the sender, subject, and a snippet of the email to be processed further.
   
   Step 2: Classify Appointment Requests with GPT-4
   
   Not every email needs a calendar response. Here’s where GPT-4 comes into play.
   
   An OpenAI-powered text classifier is used to determine if the incoming email is an appointment request. It analyzes the email’s subject and content snippet and categorizes it under "is_appointment". If the email doesn't fit the criteria, it's discarded, preventing unnecessary processing and replies.
   
   Step 3: Availability Check via Google Calendar
   
   When a valid appointment request is found, the Agent node—another GPT-4 model enhanced with rule-based messaging—takes over. But before it can suggest a reply, it needs to know when you're free.
   
   The Google Calendar node fetches your availability for the next month. It pulls all events from your primary calendar and limits the result to ensure only personal availability, not public holidays or unrelated calendars, are considered.
   
   This data is passed to the AI assistant, allowing it to make calendar-aware decisions.
   
   Step 4: Compose Smart Replies Using GPT-4
   
   Now equipped with context (email content and calendar availability), the GPT-4-powered Agent generates a custom reply.
   
   The system prompt for GPT-4 is carefully crafted:
   - Encourage specificity in time proposals.
   - Ensure a buffer of 15 minutes between meetings.
   - Always suggest a new time if there are conflicts.
   
   This controlled prompting ensures the output remains professional, timely, and considerate of the user’s schedule.
   
   Step 5: Send Reply and Mark Email as Read
   
   Once the AI finishes crafting the reply, the “Send reply” Gmail node swings into action. It replies directly to the original email thread using the generated message.
   
   Following this, the workflow uses another Gmail node to mark the email as read, ensuring it won’t be processed again. This is a small but important step in maintaining workflow integrity.
   
   Behind the Scenes: Smart Use of AI + Automation
   
   What makes this workflow special is the seamless integration of different components:
   
   - Gmail API: Incoming triggers, message sending, and marking as read.
   - Google Calendar API: Fetching availability tailored to the user’s real-time schedule.
   - OpenAI’s GPT-4o-mini: Classification and response generation, including understanding scheduling nuances.
   - n8n orchestrates it all: Executing logic, data routing, and ensuring the entire flow runs without manual input.
   
   Room for Customization
   
   Here are a few ideas for extending the workflow:
   
   - Add a Slack or Telegram notification when an appointment is confirmed.
   - Trigger calendar invites automatically after a time is agreed upon.
   - Integrate with CRMs like HubSpot or Salesforce to log responses.
   
   Conclusion
   
   This n8n workflow demonstrates the potent synergy between AI and automation. By combining tools like Gmail, Google Calendar, and GPT-4, you can create a truly intelligent scheduling assistant that saves time and keeps your calendar organized without lifting a finger.
   
   Whether you're a productivity enthusiast or a business professional, this setup provides a glimpse into the future of smart automation—available today through open-source tools and powerful APIs.
   
   With technology like this at your fingertips, managing emails and maintaining your schedule isn’t a chore anymore—it’s just another well-automated task.

5. Set credentials for each API node (keys, OAuth) in Credentials.
6. Run a test via Execute Workflow. Inspect Run Data, then adjust parameters.
7. Enable the workflow to run on schedule, webhook, or triggers as configured.

Tips: keep secrets in credentials, add retries and timeouts on HTTP nodes, implement error notifications, and paginate large API fetches.

Validation: use IF/Code nodes to sanitize inputs and guard against empty payloads.

Why Automate This with AI Agents

AI‑assisted automations offload repetitive, error‑prone tasks to a predictable workflow. Instead of manual copy‑paste and ad‑hoc scripts, your team gets a governed pipeline with versioned state, auditability, and observable runs.

n8n’s node graph makes data flow transparent while AI‑powered enrichment (classification, extraction, summarization) boosts throughput and consistency. Teams reclaim time, reduce operational costs, and standardize best practices without sacrificing flexibility.

Compared to one‑off integrations, an AI agent is easier to extend: swap APIs, add filters, or bolt on notifications without rewriting everything. You get reliability, control, and a faster path from idea to production.

Best Practices

• Credentials: restrict scopes and rotate tokens regularly.
• Resilience: configure retries, timeouts, and backoff for API nodes.
• Data Quality: validate inputs; normalize fields early to reduce downstream branching.
• Performance: batch records and paginate for large datasets.
• Observability: add failure alerts (Email/Slack) and persistent logs for auditing.
• Security: avoid sensitive data in logs; use environment variables and n8n credentials.

FAQs

Can I swap integrations later? Yes. Replace or add nodes and re‑map fields without rebuilding the whole flow.

How do I monitor failures? Use Execution logs and add notifications on the Error Trigger path.

Does it scale? Use queues, batching, and sub‑workflows to split responsibilities and control load.

Is my data safe? Keep secrets in Credentials, restrict token scopes, and review access logs.