# Sessions (Python)
Track multi-turn conversations by grouping traces with session IDs.
## Setup
```python
from openinference.instrumentation import using_session
with using_session(session_id="user_123_conv_456"):
response = llm.invoke(prompt)
```
## Best Practices
**Bad: Only parent span gets session ID**
```python
from openinference.semconv.trace import SpanAttributes
from opentelemetry import trace
span = trace.get_current_span()
span.set_attribute(SpanAttributes.SESSION_ID, session_id)
response = client.chat.completions.create(...)
```
**Good: All child spans inherit session ID**
```python
with using_session(session_id):
response = client.chat.completions.create(...)
result = my_custom_function()
```
**Why:** `using_session()` propagates session ID to all nested spans automatically.
## Session ID Patterns
```python
import uuid
session_id = str(uuid.uuid4())
session_id = f"user_{user_id}_conv_{conversation_id}"
session_id = f"debug_{timestamp}"
```
Good: `str(uuid.uuid4())`, `"user_123_conv_456"`
Bad: `"session_1"`, `"test"`, empty string
## Multi-Turn Chatbot Example
```python
import uuid
from openinference.instrumentation import using_session
session_id = str(uuid.uuid4())
messages = []
def send_message(user_input: str) -> str:
messages.append({"role": "user", "content": user_input})
with using_session(session_id):
response = client.chat.completions.create(
model="gpt-4",
messages=messages
)
assistant_message = response.choices[0].message.content
messages.append({"role": "assistant", "content": assistant_message})
return assistant_message
```
## Additional Attributes
```python
from openinference.instrumentation import using_attributes
with using_attributes(
user_id="user_123",
session_id="conv_456",
metadata={"tier": "premium", "region": "us-west"}
):
response = llm.invoke(prompt)
```
## LangChain Integration
LangChain threads are automatically recognized as sessions:
```python
from langchain.chat_models import ChatOpenAI
response = llm.invoke(
[HumanMessage(content="Hi!")],
config={"metadata": {"thread_id": "user_123_thread"}}
)
```
Phoenix recognizes: `thread_id`, `session_id`, `conversation_id`
## See Also
- **TypeScript sessions:** `sessions-typescript.md`
- **Session docs:** https://docs.arize.com/phoenix/tracing/sessions
