# ModelInvocationKey

> **Class** in `deepagents_code`

📖 [View in docs](https://reference.langchain.com/python/deepagents-code/_session_stats/ModelInvocationKey)

Stable identity of one model invocation in the usage ledger.

## Signature

```python
ModelInvocationKey(
    self,
    invocation_id: str,
)
```

## Constructors

```python
__init__(
    self,
    invocation_id: str,
) -> None
```

| Name | Type |
|------|------|
| `invocation_id` | `str` |


## Properties

- `invocation_id`

---

[View source on GitHub](https://github.com/langchain-ai/deepagents/blob/caaa7e7c12d214afa5cf0a1afed8eb6232aa6f7b/libs/code/deepagents_code/_session_stats.py#L183)