Grammarly

https://grammarly.com
33
Fair
Agent Native Score
Free Tier

Grammarly is an AI-powered writing assistant that checks grammar, spelling, clarity, tone, and plagiarism in real-time across web and desktop applications. It offers both free and premium tiers with varying levels of writing suggestions and analytics.

Categories: Writing · Text Analysis
Checklist Breakdown

11 of 33 checks passed. 14 unscored.

Discovery 50%

Can an agent find and understand this tool without a web search?

✗ Published OpenAPI/Swagger spec
✗ Has llms.txt or llms-full.txt
✗ Has an MCP server (official or well-maintained)
✗ MCP server listed in a public registry
✓ API reference docs are publicly accessible
✓ Docs include runnable code examples
✓ Has a public changelog or release notes
✓ Has a public status page
Auth & Onboarding 33%

Can an agent create an account and get credentials without human intervention?

✗ Signup does not require CAPTCHA
✗ Signup does not require phone verification
✗ Supports API key auth (not only OAuth)
✗ API key obtainable without manual approval
✓ No mandatory billing info to start
✓ Can sign up without creating an organization
Pricing 100%

Can an agent operate autonomously without upfront payment or contracts?

✓ Has a free tier
✓ Usage-based pricing available
✓ No minimum contract or commitment
✓ Pricing page is public (no 'contact sales')
✓ Free tier sufficient for testing (not just a trial)
Agent Tooling Not yet scored

How well does the API work for non-human consumers?

— SDK available in 2+ languages
— Structured error responses (JSON with error codes)
— Idempotency support on write endpoints
— Pagination on list endpoints
— Webhook/event support
— Sandbox or test mode available
— Rate limit headers in responses
— Consistent REST resource naming
Reliability Not yet scored

Does the tool fail gracefully when an agent makes a mistake?

— Meaningful error messages (not just 500)
— 429 responses include Retry-After header
— Documented uptime SLA (99.9%+)
— Graceful degradation under rate limits
— Request IDs in responses for debugging
— API versioning supported
Reviewer Notes

Grammarly lacks critical agent-native infrastructure—no MCP server, OpenAPI spec, or llms.txt—making programmatic discovery difficult. Account creation requires email verification and OAuth setup, blocking automated signup. The API is not publicly documented for agent use; Grammarly primarily offers browser extensions and web interfaces rather than agent-friendly SDKs or structured APIs. While Grammarly is reliable and widely used, it's fundamentally designed for human end-users rather than autonomous agents, making it poorly suited for integration into agentic workflows.

Let your agents find tools like Grammarly

Install the Agent Native Registry MCP server. Your agents can search, compare, and score tools mid-task.

claude mcp add --transport http agent-native-registry https://agentnativeregistry.com/api/mcp