The AI proofreading tool at the bottom of the grading interface scans a submission for spelling and grammar issues and lets you insert each correction into the feedback field with one click. It’s intended as a quick mechanical check on objective errors, not a style or tone review.

Running a Proofreading Pass

1. Open a submission in the grading interface.
2. Below the document viewer on the left, click Check Proofreading.

3. Wait for the AI to process the submission. Long submissions are processed in chunks with a progress indicator.
4. Review the list of detected issues. Each issue shows the original excerpt, the suggested correction, the issue type (spelling or grammar), surrounding context, and the paragraph number.
5. For each issue you want to include in your feedback, click Insert into Feedback. The correction is appended to the feedback field in a consistent format, such as [Proofreading: "recieve" → "receive"].
6. Insert as many or as few issues as you like.

Chunked Processing for Long Submissions

Submissions are automatically split into chunks of up to 2,500 words so each chunk can complete within typical host timeout limits. A progress indicator shows which chunk is currently processing. A proofreading pass counts as a single AI request against your site’s AI limits, no matter how many chunks it processes.

Each chunk is sent to the AI separately. When all chunks finish, the issues are merged together and paragraph numbers are adjusted so they reference the full submission (not individual chunks).

Proofreading Does Not Retry

This is the most important difference between proofreading and AI-assisted grading: proofreading does not retry on failure.

If a chunk fails for any reason (e.g. provider timeout, network error, server error, rate limit, invalid API key, etc.) the entire proofreading pass stops and an error is shown. Chunks that completed before the failure are discarded along with the failed chunk. If the issue is because of a temporary provider issue, retry the proofreading attempt

Hallucination Filter

The AI is instructed to report only errors where the original excerpt appears verbatim in the submission. As a second line of defense, the Assignment School plugin validates every issue the AI returns: if the excerpt can’t actually be found in the submission text, the issue is discarded before it reaches the teacher.

Setting a Proofreading Locale

The proofreading locale tells the AI which regional spelling variants to expect.

1. Navigate to Assignments > Settings > Integrations.
2. Find the Proofreading Locale setting.
3. Choose a locale (for example, English (United States), English (United Kingdom), or English (Canada)).
4. Click Save.

If no locale is set, the AI uses your WordPress site’s locale. Leaving the locale unset is fine for most sites — only set it if your students write in a variant that differs from your site’s default.

Supported Submission Types

Proofreading works with the same submission types as AI grading:

• Text editor submissions
• DOCX, ODT, and RTF uploads (extracted to Markdown)
• TXT uploads (plain text)
• PDF uploads (passthrough when enabled; stored text otherwise)

Image-only submissions are not supported — the Proofread button does not appear for them.

What Proofreading Is Not

• Not a style or tone review — it focuses on objective spelling and grammar issues
• Not a rubric substitute — use AI-assisted grading for rubric-aware suggestions
• Not a final edit — the AI catches most issues, but human review is still recommended