> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fonoster.com/llms.txt
> Use this file to discover all available pages before exploring further.

# API

> Fonoster's API is gRPC, with grpc-web for browsers and a few HTTP routes, and the Node SDK is the way to call it.

![API: one endpoint. The Node SDK over gRPC, the browser over grpc-web, and plain HTTP on /api/records and /api/regions all reach api.fonoster.ai, or your install's address.](https://mintcdn.com/fonoster/GsxtawNPYOQvohG4/images/reference-api/banner-light.png?fit=max\&auto=format\&n=GsxtawNPYOQvohG4\&q=85\&s=df221cd3605407f3a34bfc1cd4d240e1)

Fonoster's API is gRPC. Every resource you manage (applications, numbers, trunks, domains, SIP
agents, calls, webhooks, providers, secrets, API keys and workspaces) is a gRPC service in a
`fonoster.<resource>.v1beta2` package. Browsers reach the same services through grpc-web, on the
same endpoint: `api.fonoster.ai` on Fonoster Cloud, or your install's address when you self-host.

A few features are plain HTTP routes on that endpoint instead, such as call records under
`/api/records` (search, recordings, erasure and retention) and regions under `/api/regions`. Every
request names the workspace with its access key ID (`WO…`) and carries an access token from an
API key.

You don't need to call any of this directly. Use the Node SDK: it wraps every gRPC service and HTTP
route, signs in with your API key and renews the token for you.

> **[@fonoster/sdk on npm](https://www.npmjs.com/package/@fonoster/sdk)**
>
> Install the SDK for Node.js and the browser.

> **[Node SDK reference](https://docs.fonoster.com/reference/sdk.md)**
>
> Every client class and method, with its parameters and results.


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