# init

Initialize the Fiddler client with connection parameters and global configuration.

This function establishes a connection to the Fiddler platform and configures the global client state. It handles authentication, server compatibility validation, logging setup, and creates the singleton connection instance used throughout the client library.

## Parameters

| Parameter  | Type    | Required                       | Default | Description                                                       |
| ---------- | ------- | ------------------------------ | ------- | ----------------------------------------------------------------- |
| `url`      | `str`   | ✗                              | `None`  | The base `URL` to your Fiddler platform instance                  |
| `token`    | `str`   | ✗                              | `None`  | Authentication token obtained from the Fiddler UI Credentials tab |
| `proxies`  | \`dict  | None\`                         | ✗       | `None`                                                            |
| `timeout`  | \`float | tuple\[float, float] \| None\` | ✗       | `None`                                                            |
| `verify`   | `bool`  | ✗                              | `True`  | Whether to verify server's `TLS` certificate                      |
| `validate` | `bool`  | ✗                              | `True`  | Whether to validate server/client version compatibility           |

## Raises

* **ValueError** -- If url or token parameters are empty
* **IncompatibleClient** -- If server version is incompatible with client version
* **ConnectionError** -- If unable to connect to the Fiddler platform **Return type:** None

## Examples

Basic initialization:

```python
import fiddler as fdl

fdl.init(
    url="https://your-instance.fiddler.ai",
    token="your-auth-token"
)
```

Initialization with custom timeout and proxy:

```python
fdl.init(
    url="https://your-instance.fiddler.ai",
    token="your-auth-token",
    timeout=(10.0, 60.0),  # 10s connect, 60s read timeout
    proxies={"https": "https://proxy.company.com:8080"}
)
```

Initialization for development with relaxed settings:

```python
fdl.init(
    url="https://your-instance.fiddler.ai",
    token="dev-token",
    verify=False,  # Skip SSL verification
    validate=False,  # Skip version compatibility check
)
```

{% hint style="info" %}
The client implements automatic retry strategies for transient failures. Configure retry duration via FIDDLER\_CLIENT\_RETRY\_MAX\_DURATION\_SECONDS environment variable (default: 300 seconds).
{% endhint %}

Logging is performed under the 'fiddler' namespace at INFO level. If no root logger is configured, a stderr handler is automatically attached unless auto\_attach\_log\_handler=False.