# 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`                                  | ✓        | `-`     | The base `URL` to your Fiddler platform instance                          |
| `token`    | `str`                                  | ✓        | `-`     | Authentication token obtained from the Fiddler UI Credentials tab         |
| `proxies`  | `dict \| None`                         | ✗        | `None`  | Dictionary mapping protocol to proxy `URL` for `HTTP` requests            |
| `timeout`  | `float \| tuple[float, float] \| None` | ✗        | `None`  | `HTTP` request timeout settings (float or tuple of connect/read timeouts) |
| `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.


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