> ## Documentation Index
> Fetch the complete documentation index at: https://docs.langtrace.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Filtering Traces by Session ID
> Langtrace SDK allows you to pass a session ID to traces to filter them later.
## What is a Session ID?
A session ID is a unique identifier for a user session. It is useful to group traces together for a single user session.
## How to pass a session ID to traces
In order to pass a session ID to traces, you can use the `inject_additional_attributes` function (Python) or `withAdditionalAttributes` function (Typescript).
## Usage
For python, you can use the `inject_additional_attributes` function to pass a session ID to traces.
```python theme={null}
from langtrace.utils import inject_additional_attributes
inject_additional_attributes(lambda: None, {"session.id": "unique-session-id"})
```
For Typescript, you can use the `withAdditionalAttributes` function to pass a session ID to traces.
```typescript theme={null}
withAdditionalAttributes(async () => {
// your code here
}, { "session.id": "unique-session-id" });
```
## How to filter traces by session ID
To filter traces by session ID, you can use the `session.id` filter in the UI. Additionally, you can also see the session ID of each trace in the UI.
