LanguageTool: 1 read and 1 write, one client

Grammar, spelling and style checking in 30 languages. The public API needs no key. Every call below is available over HTTP, through the SDK and as a tool for a coding agent, with the same arguments and the same meter.

What LanguageTool can do here

The integration exposes 1 read and 1 write, each with a declared input and output schema rather than a page of documentation you would have to translate. Grammar, spelling and style checking in 30 languages. The public API needs no key.

How it authenticates

LanguageTool authenticates with a apiKey, supplied per request or stored once against your account and sealed at rest. On our side the same value is read from apiKey and username when we broker the call for you.

Called by name, not by capability

LanguageTool does not currently map onto a vendor-neutral capability, so you call its operations by name. That is the right shape when you genuinely mean this provider — which, for a service with its own model of the world, is most of the time.

Its own limits

LanguageTool publishes its own limits — requests: {"limit":20,"windowMs":60000} — and we pass its throttling response back to you untouched rather than retrying into it.

• languages — read: Which languages and variants are supported. The connection test.
• check — write: Proofread a piece of text and return every issue found.

Questions

Do I have to bring my own API keys?

You can, and that lane is free for ever — pass your key on the request or store it against your account, and we are one proxy hop. The paid lane is the other direction: we call 226 providers with our credentials so you never register anywhere. Both go through the same client and the same operation names.

What happens to a key I store here?

It is sealed with AES-256-GCM before it reaches the database and is only ever opened to make the call you asked for. It is scoped to your account, it is never logged, and deleting the connection deletes it. For an OAuth provider we hold a refresh token instead, and revoking the link at the provider stops the calls here immediately.

What happens when a provider changes its API?

The operation contract is declared, so a response that no longer matches is a refusal rather than a silently wrong answer. The contract does not coerce types — a field declared a number that arrives as a string is rejected at the edge, on the way in and on the way out.