# TunnelConnectionRefusedError

> **Class** in `langsmith`

📖 [View in docs](https://reference.langchain.com/python/langsmith/sandbox/_exceptions/TunnelConnectionRefusedError)

Nothing is listening on the target port inside the sandbox.

## Signature

```python
TunnelConnectionRefusedError(
    self,
    message: str,
    *,
    port: int,
)
```

## Extends

- `TunnelError`

## Constructors

```python
__init__(
    self,
    message: str,
    *,
    port: int,
)
```

| Name | Type |
|------|------|
| `message` | `str` |
| `port` | `int` |


## Properties

- `port`

---

[View source on GitHub](https://github.com/langchain-ai/langsmith-sdk/blob/cf0366388873e33ef593235c1d0c7e561db79cfb/python/langsmith/sandbox/_exceptions.py#L313)