How to build a Writing Feedback Assistant

TL;DR

What it does:

• Automates the process of reviewing student essays by:

  • Accepting a student’s name and essay upload

  • Accepting assignment guidelines upload

  • Using AI to generate feedback based on the essay and guidelines

  • Formatting the feedback for the student

  • Logging the feedback and file references to a Google Sheet for teacher review

Who it’s for:

• Teachers and educators who want to streamline essay grading and feedback

• Students submitting essays for assignments

• School administrators seeking to centralize and track student feedback

Time to value:

• Immediate: Once set up, teachers and students can use it right away

• No manual review or formatting needed—AI and automation handle everything

Output:

• A well-formatted feedback report for the student, shown instantly

• A log entry in a Google Sheet with feedback, essay file link, and guidelines file link for teacher records

Common Pain Points of Providing Feedback

• Manual essay review is time-consuming and inconsistent

• Teachers struggle to provide detailed, criteria-based feedback for every student

• Tracking which feedback was given to which student can be messy

• Students may not understand vague or generic feedback

• Administrative overhead in logging and organizing feedback for future reference

What the Agent Delivers

• Automated, criteria-based feedback: AI reviews essays against provided guidelines, ensuring fairness and clarity

• Instant, formatted student reports: Students receive clear, structured feedback as soon as they submit

• Centralized teacher records: All feedback and file references are logged in a Google Sheet for easy review and auditing

• Reduced teacher workload: Frees up time for teachers to focus on instruction, not paperwork

• Consistency: Every student is evaluated against the same rubric/guidelines

Want to see this agent in action? Check out the video tutorial below.

Step-by-Step Build (StackAI Nodes)

1) Student Name (Input Node)

What it does:

• Collects the student’s name as text input.

• This is a simple text field; connect it to downstream nodes if you want to personalize feedback or log the student’s name.

Goal:

• Identify which student the essay and feedback belong to.

2) Student Essay (Files Node)

What it does:

• Allows the user to upload the student’s essay file (supports various formats).

• Extracts the text for AI processing.

• Set as user-exposed so students/teachers can upload files directly.

Goal:

• Provide the essay content for review.

3) Assignment Guidelines (Files Node)

What it does:

• Allows upload of the assignment’s grading criteria or rubric.

• Extracts the text for AI reference.

• Also user-exposed for easy upload.

Goal:

• Give the AI a clear standard to compare the essay against.

4) OpenAI (LLM Node)

What it does:

• Uses GPT-4o-mini to analyze the essay in the context of the guidelines.

• Generates detailed, criteria-based feedback.

• The system prompt is tailored for Romeo and Juliet assignments, but can be adapted for other topics.

• Receives essay and guidelines as input.

Goal:

• Automate the feedback process with high-quality, rubric-aligned comments.

Instructions

You are a writing feedback assistant for the Romeo and Juliet assignment. Your role is to review the uploaded student essays and provide constructive feedback based on the assignment guidelines. 
  Ensure your feedback is clear, specific, and aligned with the criteria outlined in the guidelines

Prompt

Text from scanning the user's essay:

<essay>

{doc-0}

</essay>



Assignment guidelines:

<guidelines>

{doc-1} 

</guidelines>



Respond with a report providing feedback to the user's writing based on the given guidelines.

5) Feedback Template (Template Node)

What it does:

• Formats the AI’s feedback into a clear, student-friendly markdown report.

• You can customize the template for your school’s branding or feedback style.

Goal:

• Ensure feedback is easy to read and professional.

6) Write Sheet (Action Node)

• What it does:

  • Logs the feedback, essay file link, and guidelines file link to a Google Sheet for teacher review.

  • Uses a pre-configured Google Workspace connection and spreadsheet.

  • To log data, you must specify:

    • The Google Sheet to write to (spreadsheet_id)

    • The specific sheet/tab (sheet_name)

    • The data to write (as a JSON object or plain text)

    • The data field can include key-value pairs like:
      {"Essay Feedback": "{llm-0}", "Essay File": "{doc-0.file_urls}", "Guidelines File": "{doc-1.file_urls}"}

Goal:

• Centralize all feedback and submissions for easy tracking and auditing.

7) Output (Output Node)

What it does:

• Displays the formatted feedback to the student immediately after processing.

• Connects directly from the template node for clean output.

Goal:

• Provide instant, actionable feedback to the student.