# Belugas Constructor

Creates an instance of the Belugas.js SDK.

* `[provider]` (Provider | string) Optional Ethereum network provider. Defaults to Ethers.js fallback mainnet provider.
* `[options]` (object) Optional provider options.
* `RETURN` (object) Returns an instance of the Belugas.js SDK.

```
var belugas = new Belugas(window.ethereum); // web browser

var belugas = new Belugas('http://127.0.0.1:8545'); // HTTP provider

var belugas = new Belugas(); // Uses Ethers.js fallback mainnet (for testing only)

var belugas = new Belugas('ropsten'); // Uses Ethers.js fallback (for testing only)

// Init with private key (server side)
var belugas = new Belugas('https://mainnet.infura.io/v3/_your_project_id_', {
  privateKey: '0x_your_private_key_', // preferably with environment variable
});

// Init with HD mnemonic (server side)
var belugas = new Belugas('mainnet' {
  mnemonic: 'clutch captain shoe...', // preferably with environment variable
});
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.belugas.io/aquarius.js/aquarius-constructor.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.