# read_thread

> **Method** in `langsmith`

📖 [View in docs](https://reference.langchain.com/python/langsmith/client/Client/read_thread)

Read runs for a single thread.

.. admonition:: Deprecated

    Use :meth:`langsmith.Client.threads.list_traces` instead.
    See https://docs.langchain.com/langsmith/smithdb-sdk-migration#threads-list-traces for the migration guide.
    Will be removed after Jan 31, 2027.

## Signature

```python
read_thread(
    self,
    *,
    thread_id: str,
    project_id: Optional[Union[ID_TYPE, Sequence[ID_TYPE]]] = None,
    project_name: Optional[Union[str, Sequence[str]]] = None,
    is_root: bool = True,
    limit: Optional[int] = None,
    select: Optional[Sequence[str]] = None,
    filter: Optional[str] = None,
    order: Literal['asc', 'desc'] = 'asc',
    **kwargs: Any = {},
) -> Iterator[ls_schemas.Run]
```

## Parameters

| Name | Type | Required | Description |
|------|------|----------|-------------|
| `thread_id` | `str` | Yes | Thread id (required). |
| `project_id` | `Optional[Union[ID_TYPE, Sequence[ID_TYPE]]]` | No | Project id(s) (required when not using project_name). (default: `None`) |
| `project_name` | `Optional[Union[str, Sequence[str]]]` | No | Project name(s) (required when not using project_id). (default: `None`) |
| `is_root` | `bool` | No | If True, return only root runs. Default True. (default: `True`) |
| `limit` | `Optional[int]` | No | Maximum number of runs to return. (default: `None`) |
| `select` | `Optional[Sequence[str]]` | No | Fields to select. (default: `None`) |
| `filter` | `Optional[str]` | No | Additional filter expression. (default: `None`) |
| `order` | `Literal['asc', 'desc']` | No | Sort order for runs (e.g. "asc" for chronological). Default "asc". (default: `'asc'`) |
| `**kwargs` | `Any` | No | Additional arguments passed to the runs query. (default: `{}`) |

## ⚠️ Deprecated

read_thread() is deprecated and will be removed after Jan 31, 2027. Use client.threads.list_traces() instead. See https://docs.langchain.com/langsmith/smithdb-sdk-migration#threads-list-traces for the migration guide.

---

[View source on GitHub](https://github.com/langchain-ai/langsmith-sdk/blob/3f9fe09d8e0698d65aa8bb63ac3316dfcb2ca947/python/langsmith/client.py#L4257)