Plugin

Grammarly Pack

Five model-agnostic Grammarly operator skills for secure access, document evaluation, API reliability, data safety, and license governance.

Type: Plugin
Repository: jeremylongshore/tons-of-skills-marketplace
GitHub stars: 2.8k
License: MIT
Repo last updated: Sep 27, 2026
Source file: plugins/saas-packs/grammarly-pack/.claude-plugin/plugin.json
Version: 2.0.0
Author: Jeremy Longshore

What Grammarly Pack is

Grammarly Pack is a plugin published in the jeremylongshore/tons-of-skills-marketplace repository on GitHub, which has about 2.8k stars. The repository describes itself as: “Model-agnostic agent-skills platform with a harness-free canonical layer, verified adapters, and the ccpi package manager. Explore at tonsofskills.com.”

A plugin is a package that bundles skills, slash commands, subagents, hooks, and MCP connectors so they install together. Plugins are plain files with a manifest at .claude-plugin/plugin.json, and they work in both Claude Code and Claude Cowork.

Installing Grammarly Pack adds everything it ships in one step. Connectors inside a plugin still need to be connected separately, and hooks and subagents only run in Cowork and Claude Code, not in regular chat.

How to install Grammarly Pack

Claude Code

Add the repository as a plugin marketplace: claude plugin marketplace add jeremylongshore/tons-of-skills-marketplace
Install the plugin: claude plugin install grammarly-pack@<marketplace-name>, using the marketplace name from the repository's .claude-plugin/marketplace.json.
Restart the session if the new skills or commands don't appear straight away.

Claude Cowork

Open Customize → Plugins and choose Add marketplace.
Enter jeremylongshore/tons-of-skills-marketplace (the owner/repo shorthand works for GitHub).
Find Grammarly Pack in the list, click Install, then connect any connectors it needs from its Connectors tab.

New to extending Cowork? Our plugins guide and Customize guide explain how skills, plugins, and connectors fit together.

Inside the source file

An excerpt from plugins/saas-packs/grammarly-pack/.claude-plugin/plugin.json, shared under the repository's MIT license. Read the full file on GitHub.

v2.0.0 — five model-agnostic Agent Skills for safe Grammarly API operations: access readiness, document evaluation, API reliability, content-transfer governance, and license review.

> [!IMPORTANT] > v2 replaces 24 documentation-style v1 skills whose examples included inaccurate or > undocumented API contracts. The install slug stays grammarly-pack. Review the > complete v1 to v2 migration before upgrading.

Why this pack exists

The pack turns Grammarly's public developer contracts into reviewable operator workflows. Four helpers are offline analyzers. The only network-capable helper is dry-run by default and requires an exact content SHA-256 confirmation before it requests a token, creates a job, uploads a document, or polls a result.

This is not a browser writing assistant and does not emulate Grammarly suggestions. It does not invent sandbox, webhook, pricing, quota, account, usage, or direct-text APIs.

Installation

Install the repository's plugin bundle in a compatible plugin host:

/plugin install grammarly-pack@claude-code-plugins-plus

The skill directories also follow the Agent Skills format and can be consumed by other compatible hosts. Deterministic helpers require Python 3.10 or newer and use only the standard library.

The five skills

Security invariants

OAuth credentials come only from GRAMMARLY_CLIENT_ID and GRAMMARLY_CLIENT_SECRET; tools never accept or print secret values.
Raw text, document previews, response bodies, bearer tokens, presigned URLs, emails, names, and raw license resource IDs are rejected from diagnostic inputs.
Live document transfer requires a dry-run digest, upload-origin inspection, a READY data-safety manifest bound to both destinations, and explicit --execute.
Job creation is not automatically retried because Grammarly does not document idempotency.
Local polling caps are operator controls, not claims about Grammarly processing time.
Failed or pending analysis is never replaced by a fabricated score.
License governance emits candidates for human review and does not call DELETE APIs.
Unknown endpoints, fields, statuses, scopes, or documentation conflicts fail closed.

Official API surface

Contract evidence and known documentation ambiguities are recorded in 000-docs/002-RL-RSRC-grammarly-api-contract-audit.md.

v1 to v2 migration

Every removed ID has an explicit disposition in migration-map.json.

Because the old IDs had no alias mechanism, their removal is a deliberate major-version change. No unsafe tombstone skill remains active or discoverable.

Design and verification

000-docs/000-INDEX.md — evidence and decision index
000-docs/003-RL-RSRC-databricks-production-benchmark.md — production benchmark
000-docs/004-AT-ADEC-grammarly-v2-cto-decision.md — scope and safety decision
tests/test_grammarly_pack.py — offline contract, boundary, and adversarial regression suite

License

MIT

Before you install

Read the whole file first. Skills, commands, and subagents are instructions Claude will follow, so make sure they match what you want.
Check which tools, scripts, or MCP servers it uses. Local servers and scripts run with your permissions.
Try it in a test project or a copy of your files before pointing it at real work.
Pin the version you tested, and review changes before updating.
Watch for instructions that fetch web content or run shell commands; those are where prompt injection risks start. See our prompt injection guide.

FAQ

What is Grammarly Pack?

Grammarly Pack is a plugin for Claude Code and Claude Cowork from the jeremylongshore/tons-of-skills-marketplace repository on GitHub. Five model-agnostic Grammarly operator skills for secure access, document evaluation, API reliability, data safety, and license governance.

How do I install Grammarly Pack in Claude Code?

Add the repository as a plugin marketplace: claude plugin marketplace add jeremylongshore/tons-of-skills-marketplace Install the plugin: claude plugin install grammarly-pack@<marketplace-name>, using the marketplace name from the repository's .claude-plugin/marketplace.json. Restart the session if the new skills or commands don't appear straight away.

Can I use Grammarly Pack in Claude Cowork?

Open Customize → Plugins and choose Add marketplace. Enter jeremylongshore/tons-of-skills-marketplace (the owner/repo shorthand works for GitHub). Find Grammarly Pack in the list, click Install, then connect any connectors it needs from its Connectors tab.

Is Grammarly Pack safe to install?

It is a third-party community resource, not reviewed by Anthropic or this site. Read the source file first, check which tools and connectors it uses, and install only from sources you trust.

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Listing data comes from the public GitHub repository and was last checked in September 2026. Excerpts are © their authors and shared under MIT. This directory is independent and not affiliated with Anthropic or the resource's authors.