Grammarly Document Evaluator

Overview

Run Grammarly's three documented document APIs without inventing a direct-text endpoint. The helper is dry-run by default. Before upload, it can create a metadata-only request that reveals only the sanitized presigned origin for approval. Inspection requires an INSPECTION_READY manifest before OAuth. Live execution requires an exact digest and a READY closed-schema safety manifest bound to the operation, bytes, and both destinations. It reads OAuth credentials only from the process environment, bounds polling locally, and emits no token, full upload URL, raw request identifier, or document text.

Prerequisites

Grammarly Enterprise or an institution-wide Grammarly for Education license with API access.
Python 3.10 or newer.
One supported regular, non-symlink file: .doc, .docx, .odt, .txt, or .rtf.
For live execution only, GRAMMARLY_CLIENT_ID and GRAMMARLY_CLIENT_SECRET in the environment.
The exact read/write scopes for the selected operation; see API contract.

Instructions

Classify the operation as writing-score, ai-detection, or plagiarism.

Run the helper without --execute from this skill directory:

python3 scripts/run_document_evaluation.py \
  --operation writing-score \
  --file /approved/input/document.txt

Review the endpoint, scopes, beta marker, local constraints, retention boundary, and content_sha256. A dry run does not contact Grammarly.
Create a preliminary manifest with presigned_upload_origin: null and presigned_upload_origin_approved: false. Continue only when the safety guardian returns INSPECTION_READY, then inspect the actual byte destination. This creates a provider request but performs no upload and emits no signed URL:
```
python3 scripts/run_document_evaluation.py \
  --operation writing-score \
  --file /approved/input/document.txt \
  --inspect-upload-origin \
  --confirm-content-sha256 sha256:REVIEWED_DIGEST \
  --approval-manifest /approved/metadata/grammarly-inspection.json
```
Put that exact sanitized origin and the dry-run metadata into the closed manifest for grammarly-data-safety-guardian. Continue only when it returns READY.

If live transfer is authorized, execute with both bindings:

python3 scripts/run_document_evaluation.py \
  --operation writing-score \
  --file /approved/input/document.txt \
  --execute \
  --confirm-content-sha256 sha256:REVIEWED_DIGEST \
  --approval-manifest /approved/metadata/grammarly-transfer.json

Treat COMPLETED and FAILED as terminal. A local polling-budget exhaustion means only that this helper stopped; Grammarly documents no processing-time SLA.
Interpret all score fields on the documented 0..1 scale. Never convert them into unsupported pass/fail policy unless the operator supplies that policy separately.

Output

Dry run: a JSON transfer plan with content digest, byte size, extension, endpoint, scopes, beta status, and documented retention boundaries.
Upload-origin inspection: sanitized public HTTPS origin, hashed request identifier, hashed full URL, and document_uploaded: false; the signed path/query remains secret.
Execute: the same plan plus approved origin, hashed request identifier, terminal status, and exact API-specific score fields when completed.
No raw content, OAuth token, client secret, presigned URL, or raw provider body.

Error Handling

Failure	Meaning	Safe response
Unsupported, empty, oversized, symlinked, or changing file	Local safety check failed	Stop and prepare a new approved regular file.
Fewer than 30 words or more than 100,000 UTF-8 characters in `.txt`	Documented text constraint failed	Correct the source; do not split and recombine scores.
Digest confirmation mismatch	Reviewed bytes differ from execution bytes	Stop and repeat dry run and approval.
Missing, blocked, or mismatched approval manifest	Governance decision does not bind this operation, content, phase, or origin	Stop before OAuth or before upload.
Newly issued upload origin differs from the approved inspected origin	Provider byte destination changed	Stop before PUT; inspect and approve again.
OAuth or API HTTP failure	Provider boundary rejected the operation	Report only phase and status code; never dump bodies or credentials.
Unknown status or result field	Response differs from the pinned contract	Fail closed and verify current official documentation.
Polling budget exhausted	Local cap reached; provider limit is undocumented	Return deferred/unknown, never fabricate a score.

Examples

AI detection request: choose ai-detection, disclose that it is Beta, require ai-detection-api:read,write, and return only average_confidence and ai_generated_percentage on a 0..1 scale.

“Send this paragraph directly to /v1/check”: refuse that contract. Grammarly's document APIs require a filename-only creation body, a presigned file upload, and status polling.

Provider outage: return an explicit unavailable or deferred result. Never substitute an invented score.

grammarly-document-evaluator