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

# Argus DSN: The Project Connection String Explained

> A DSN (Data Source Name) connects your SDK to a specific Argus project. Learn the format, where to find your DSN, and how to use it safely.

A DSN (Data Source Name) is the connection string that tells your Argus SDK where to send events. Every project gets a unique DSN at creation time — paste it into your `init()` call once, and Argus handles the rest. Without a valid DSN, the SDK silently no-ops instead of crashing your app, but you won't receive any error data, so getting this value right from the start matters.

## DSN format

Every Argus DSN follows this structure:

```
https://PUBLIC_KEY@your-domain.com/PROJECT_ID
```

| Component         | Description                                                                                                                                                                                                                |
| ----------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `PUBLIC_KEY`      | The URL username — the portion of the DSN before the `@`. It identifies your SDK to the ingest endpoint. It is **not** a secret — safe to include in frontend code, commit to source control, or embed in build pipelines. |
| `your-domain.com` | The host where your Argus instance is running.                                                                                                                                                                             |
| `PROJECT_ID`      | The unique identifier for your project. The ingest route is scoped to this ID, so events land in exactly the right project.                                                                                                |

## Finding your DSN

<Steps>
  <Step title="Log into the Argus dashboard">
    Navigate to your Argus instance and sign in with your account credentials.
  </Step>

  <Step title="Open your project">
    Select an existing project from the Projects Console. If you haven't created one yet, click **New Project** — your DSN is displayed immediately on the onboarding screen once the project is created.
  </Step>

  <Step title="Copy the DSN from Settings">
    Inside the project, go to **Settings**. Find the **Client key (DSN)** section and click **Copy** next to the DSN string.
  </Step>
</Steps>

## Using your DSN in code

Pass the DSN as the `dsn` property of the options object you hand to `init()`. Call `init()` once, as early as possible in your application's startup sequence — before any code that could throw.

<CodeGroup>
  ```typescript Browser theme={null}
  import { init } from '@argusdev/sdk-browser';

  init({ dsn: 'https://abc123@your-domain.com/proj456' });
  ```

  ```typescript Node.js theme={null}
  import { init } from '@argusdev/sdk-node';

  init({ dsn: 'https://abc123@your-domain.com/proj456' });
  ```

  ```typescript React theme={null}
  import { init } from '@argusdev/sdk-react';

  init({ dsn: 'https://abc123@your-domain.com/proj456' });
  ```
</CodeGroup>

## DSN validation

Argus validates the DSN synchronously inside `init()` and **throws an error immediately** if anything is wrong. Conditions that cause a throw:

* The string is not a valid URL
* The public key (the part before `@`) is missing
* The project ID (the URL path) is missing
* The protocol is anything other than `http` or `https`

This behaviour is intentional. A bad DSN is a misconfiguration, and you want to catch it at deploy time — not silently lose production error data for days.

## Security note

The DSN public key grants write-only access to a single project's ingest endpoint. It **cannot** read issues, query data, or access any other part of your account. Bundle it freely in client-side code, commit it to your repository, and include it in your build pipeline without concern.

<Warning>
  Each project has its own unique DSN. Using the wrong DSN sends your events to the wrong project — they won't appear where you expect them. Always verify the DSN matches the project you intend to monitor.
</Warning>