Grade and deliver multi-course assignment feedback with GPT-4o, Google Drive, Slack, and Gmail

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Important notice

This workflow is provided as-is. Please review and test before using in production.

1. Workflow Overview

How It Works This workflow automates business intelligence reporting by aggregating data from multiple sources, processing it through AI models, and delivering formatted dashboards via email. Desig...

Best for

Document Extraction automation workflows
AI Summarization automation workflows
advanced n8n builders looking for reusable templates

Tools used

n8n-nodes-base.webhook, n8n-nodes-base.scheduletrigger, n8n-nodes-base.set, n8n-nodes-base.httprequest, n8n-nodes-base.merge, n8n-nodes-base.code, n8n-nodes-base.if, n8n-nodes-base.postgres

Source and attribution

This workflow is cataloged by N8N Workflows and links back to its original n8n.io source page by Cheng Siong Chin.

Original n8n.io source

1.1 Workflow description

Title: Grade and deliver multi-course assignment feedback with GPT-4o, Google Drive, Slack, and Gmail
Workflow name: Grade and deliver multi-course assignment feedback with GPT-4o, Google Drive, Slack, and Gmail

How It Works

This workflow automates business intelligence reporting by aggregating data from multiple sources, processing it through AI models, and delivering formatted dashboards via email. Designed for business analysts, operations managers, and executive teams, it solves the challenge of manually compiling metrics from disparate systems into coherent reports. The system triggers on schedule or webhook, extracting data from Google Sheets, databases, and APIs. Raw data flows through transformation nodes that calculate KPIs, generate trend analyses, and create visualizations. AI models (OpenAI) provide natural language insights and anomaly detection. Results populate multiple dashboard templates—executive summary, departmental metrics, and detailed analytics—each tailored to specific stakeholder needs. Formatted reports are automatically distributed via Gmail with embedded charts and actionable recommendations. This eliminates hours of manual data gathering, reduces reporting errors, and ensures stakeholders receive timely, consistent insights.

Setup Steps

Configure Google Sheets credentials and specify source spreadsheet IDs
Set up database connections (PostgreSQL, MySQL) with read-only access
Add OpenAI API key for GPT-4 analytics and narrative generation
Set Gmail OAuth credentials for automated email delivery
Define recipient lists for each dashboard type (executive, departmental, detailed)
Customize dashboard templates with company branding and preferred KPIs

Prerequisites

Active Google Workspace account with Sheets and Gmail access.

Use Cases

Automated weekly executive dashboards with YoY comparisons.

Customization

Modify dashboard templates to match corporate branding standards.

Benefits

Reduces report preparation time by 80% through full automation.

1.2 Logical Blocks

This catalog entry is organized from the workflow JSON. The node-level section below shows the executable blocks available for review before importing the template.

2. Block-by-Block Analysis

Block 1 - Google Forms Webhook

Type / Role: n8n-nodes-base.webhook - webhook
Config choices: Version 2.1

Block 2 - LMS API Polling Schedule

Type / Role: n8n-nodes-base.scheduleTrigger - scheduleTrigger
Config choices: Version 1.3

Block 3 - Workflow Configuration

Type / Role: n8n-nodes-base.set - set
Config choices: Version 3.4

Block 4 - Fetch LMS Assignments

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.3

Block 5 - Merge Form and API Data

Type / Role: n8n-nodes-base.merge - merge
Config choices: Version 3.2

Block 6 - Normalize Submission Data

Type / Role: n8n-nodes-base.set - set
Config choices: Version 3.4

Block 7 - Validate Submission

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 8 - Check Validation Status

Type / Role: n8n-nodes-base.if - if
Config choices: Version 2.3

Block 9 - Check Duplicate Submission

Type / Role: n8n-nodes-base.postgres - postgres
Config choices: Version 2.6

Block 10 - Is Duplicate?

Type / Role: n8n-nodes-base.if - if
Config choices: Version 2.3

Block 11 - Calculate Deadline Penalty

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 12 - Upload Submission to Drive

Type / Role: n8n-nodes-base.googleDrive - googleDrive
Config choices: Version 3

Block 13 - Plagiarism Check Agent

Type / Role: @n8n/n8n-nodes-langchain.agent - agent
Config choices: Version 3.1

Block 14 - OpenAI Model - Plagiarism

Type / Role: @n8n/n8n-nodes-langchain.lmChatOpenAi - lmChatOpenAi
Config choices: Version 1.3

Block 15 - Plagiarism Result Parser

Type / Role: @n8n/n8n-nodes-langchain.outputParserStructured - outputParserStructured
Config choices: Version 1.3

Block 16 - AI Grading Agent

Type / Role: @n8n/n8n-nodes-langchain.agent - agent
Config choices: Version 3.1

Block 17 - OpenAI Model - Grading

Type / Role: @n8n/n8n-nodes-langchain.lmChatOpenAi - lmChatOpenAi
Config choices: Version 1.3

Block 18 - Grading Result Parser

Type / Role: @n8n/n8n-nodes-langchain.outputParserStructured - outputParserStructured
Config choices: Version 1.3

Block 19 - Combine Grading Results

Type / Role: n8n-nodes-base.set - set
Config choices: Version 3.4

Block 20 - Route by Exception Type

Type / Role: n8n-nodes-base.switch - switch
Config choices: Version 3.4

Block 21 - Store Submission Record

Type / Role: n8n-nodes-base.postgres - postgres
Config choices: Version 2.6

Block 22 - Update Gradebook

Type / Role: n8n-nodes-base.postgres - postgres
Config choices: Version 2.6

Block 23 - Generate Feedback HTML

Type / Role: n8n-nodes-base.html - html
Config choices: Version 1.2

Block 24 - Convert HTML to PDF

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.3

Showing the first 24 of 42 workflow blocks. Download the JSON for the full node graph.

3. Summary Table

Workflow	Grade and deliver multi-course assignment feedback with GPT-4o, Google Drive, Slack, and Gmail
Complexity	advanced
Nodes	42
Categories	Document Extraction, AI Summarization
Author	Cheng Siong Chin
Published	15 Jan 2026

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

Use the JSON export at /data/workflows/12731/12731.json as the source template for this automation.
2. Import the template into n8n

Open n8n, import the downloaded JSON, and review each node before activating the workflow.
3. Configure credentials and variables

Replace placeholder credentials, API keys, webhook URLs, account IDs, and environment-specific values with your own settings.
4. Test with sample data

Run the workflow manually or in a staging workspace, inspect node output, and confirm downstream systems receive the expected data.
5. Activate and monitor

Enable the workflow only after testing, then monitor executions, errors, and rate limits during the first production runs.

5. General Notes & Resources

Review imported nodes carefully before activation. This catalog entry is intended to help you inspect the workflow structure, understand required services, and find related templates faster.

Node names, credentials, schedules, webhook paths, and external service limits may need adjustment for your workspace.

Download workflow JSON Original n8n.io source Document Extraction workflows AI Summarization workflows

Frequently asked questions

What does Grade and deliver multi-course assignment feedback with GPT-4o, Google Drive, Slack, and Gmail do?

What do I need before importing this workflow?

Review the workflow JSON, configure any required credentials in n8n, and test the automation in a safe workspace before using it in production.

Can I customize this workflow?

Yes. Use the block-by-block analysis and the downloadable JSON to inspect each node, then adjust credentials, prompts, schedules, filters, or destinations for your Document Extraction, AI Summarization use case.

Cheng Siong Chin

203 workflows

Nodes

n8n-nodes-base.webhook n8n-nodes-base.scheduletrigger n8n-nodes-base.set n8n-nodes-base.httprequest n8n-nodes-base.merge n8n-nodes-base.code n8n-nodes-base.if n8n-nodes-base.postgres

Complexity

advanced

Published 15 Jan 2026

Likes 0

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Install path: /data/workflows/12731/12731.json

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Grade and deliver multi-course assignment feedback with GPT-4o, Google Drive, Slack, and Gmail

Workflow preview

Important notice

1. Workflow Overview

Best for

Tools used

Source and attribution

1.1 Workflow description

How It Works

Setup Steps

Prerequisites

Use Cases

Customization

Benefits

1.2 Logical Blocks

2. Block-by-Block Analysis

Block 1 - Google Forms Webhook

Block 2 - LMS API Polling Schedule

Block 3 - Workflow Configuration

Block 4 - Fetch LMS Assignments

Block 5 - Merge Form and API Data

Block 6 - Normalize Submission Data

Block 7 - Validate Submission

Block 8 - Check Validation Status

Block 9 - Check Duplicate Submission

Block 10 - Is Duplicate?

Block 11 - Calculate Deadline Penalty

Block 12 - Upload Submission to Drive

Block 13 - Plagiarism Check Agent

Block 14 - OpenAI Model - Plagiarism

Block 15 - Plagiarism Result Parser

Block 16 - AI Grading Agent

Block 17 - OpenAI Model - Grading

Block 18 - Grading Result Parser

Block 19 - Combine Grading Results

Block 20 - Route by Exception Type

Block 21 - Store Submission Record

Block 22 - Update Gradebook

Block 23 - Generate Feedback HTML

Block 24 - Convert HTML to PDF

3. Summary Table

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

2. Import the template into n8n

3. Configure credentials and variables

4. Test with sample data

5. Activate and monitor

5. General Notes & Resources

Frequently asked questions