> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://www.comet.com/docs/opik/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://www.comet.com/docs/opik/_mcp/server.

# OpenTelemetry Python SDK

# Using the OpenTelemetry Python SDK

This guide shows you how to directly instrument your Python applications with the OpenTelemetry SDK to send trace data to Opik.

## Installation

First, install the required OpenTelemetry packages:

```bash
pip install opentelemetry-api opentelemetry-sdk opentelemetry-exporter-otlp
```

## Full Example

Here's a complete example that demonstrates how to instrument a chatbot application with OpenTelemetry and send the traces to Opik:

```python
# Dependencies: opentelemetry-exporter-otlp

import os
import time
from opentelemetry import trace
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter
from opentelemetry.sdk.resources import Resource
from opentelemetry.semconv.resource import ResourceAttributes


# Configure OpenTelemetry

# For comet.com
os.environ["OTEL_EXPORTER_OTLP_ENDPOINT"] = "https://www.comet.com/opik/api/v1/private/otel"
os.environ["OTEL_EXPORTER_OTLP_HEADERS"] = "Authorization=<your-api-key>,Comet-Workspace=<your-workspace-name>,projectName=<your-project-name>"

# Configure the tracer provider
resource = Resource.create({
    ResourceAttributes.SERVICE_NAME: "opentelemetry-example"
})

# Create a tracer provider
tracer_provider = TracerProvider(resource=resource)

# Set up the OTLP HTTP exporter
otlp_exporter = OTLPSpanExporter()

# Add the exporter to the tracer provider
tracer_provider.add_span_processor(BatchSpanProcessor(otlp_exporter))

# Set the tracer provider
trace.set_tracer_provider(tracer_provider)

# Get a tracer
tracer = trace.get_tracer("example-tracer")

def main():
    # Simulate user request
    user_request = "What's the weather like today?"

    # Create a parent span representing the entire chatbot conversation
    with tracer.start_as_current_span("chatbot_conversation") as conversation_span:
        print(f"User request: {user_request}")

        # Add user request as an attribute to the parent span
        conversation_span.set_attribute("input", user_request)
        conversation_span.set_attribute("conversation.id", "conv_12345")
        conversation_span.set_attribute("conversation.type", "weather_inquiry")

        # Add thread ID as an attribute to the parent span to group related spans into
        # a single conversational thread
        conversation_span.set_attribute("thread_id", "user_12345")

        # Process the user request

        # Simulate initial processing
        time.sleep(0.2)

        # Create a child span for LLM generation using GenAI conventions
        with tracer.start_as_current_span("llm_completion") as llm_span:
            print("Generating LLM response...")

            # Create a prompt for the LLM
            llm_prompt = f"User question: {user_request}\n\nProvide a concise answer about the weather."

            # Add GenAI semantic convention attributes
            llm_span.set_attribute("gen_ai.operation.name", "completion")
            llm_span.set_attribute("gen_ai.system", "gpt")
            llm_span.set_attribute("gen_ai.request.model", "gpt-4")
            llm_span.set_attribute("gen_ai.response.model", "gpt-4")
            llm_span.set_attribute("gen_ai.request.input", llm_prompt)  # Add the prompt
            llm_span.set_attribute("gen_ai.usage.input_tokens", 10)  # Example token count
            llm_span.set_attribute("gen_ai.usage.output_tokens", 25)  # Example token count
            llm_span.set_attribute("gen_ai.usage.total_tokens", 35)   # Example token count
            llm_span.set_attribute("gen_ai.request.temperature", 0.7)
            llm_span.set_attribute("gen_ai.request.max_tokens", 100)

            # Simulate LLM thinking time
            time.sleep(0.5)

            # Generate chatbot response
            chatbot_response = "It's sunny with a high of 75°F in your area today!"

            # Set response in the LLM span
            llm_span.set_attribute("gen_ai.response.output", chatbot_response)

            print("LLM generation completed")

        # Back in parent span context
        conversation_span.set_attribute("output", chatbot_response)
        # Response has been generated

        print(f"Chatbot response: {chatbot_response}")

if __name__ == "__main__":
    main()

    # Ensure all spans are flushed before the program exits
    tracer_provider.shutdown()

    print("\nSpans have been sent to OpenTelemetry collector.")
    print("If you configured Comet.com, you can view the traces in your Comet project.")
```

Using `thread_id` as a span attribute allows you to group related spans into a single conversational thread.
Created threads can be used to evaluate multi-turn conversations as described in the [Multi-turn conversations](/evaluation/evaluate_threads) guide.

## Linking OpenTelemetry spans to an existing Opik trace

If a service instrumented with OpenTelemetry is invoked by another service that is already producing an Opik trace (via the Opik SDK or `@track`), you can link the OpenTelemetry spans to the existing Opik trace and parent span by propagating two HTTP headers (`opik_trace_id`, `opik_parent_span_id`) and calling the Opik bridging helper on the receiving side. The helper sets the `opik.trace_id` / `opik.parent_span_id` attributes on the OpenTelemetry boundary span so the Opik OTLP ingest endpoint attaches the span to the right parent.

### Recommended setup: register `OpikSpanProcessor`

`distributed_trace.attach_to_parent` only sets the Opik attributes on the *boundary* span. Children created inside that span via `start_as_current_span` inherit OTel context but not those attributes — without extra wiring they end up orphaned in a synthetic Opik trace. Register `OpikSpanProcessor` on the same `TracerProvider` as your OTLP exporter to propagate the Opik IDs down the entire attached subtree:

```python
from opentelemetry import trace
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter
from opik.integrations.otel import OpikSpanProcessor

provider = TracerProvider()
provider.add_span_processor(BatchSpanProcessor(OTLPSpanExporter()))

# Mints opik.span_id and threads opik.trace_id / opik.parent_span_id onto every
# descendant of a span that was attached via distributed_trace.attach_to_parent.
provider.add_span_processor(OpikSpanProcessor())

trace.set_tracer_provider(provider)
```

The processor stamps Opik IDs onto a span when any of the following holds, in order of precedence:

1. the parent span already carries Opik attributes (set by `attach_to_parent` on the boundary, or by an earlier processor pass);
2. they are inherited from upstream W3C `baggage` (cross-process);
3. an `@track` span is active in the current process (see below).

Spans that match none of these are left untouched, so OpenTelemetry-only traces are unaffected.

### Same-process: OpenTelemetry spans inside an `@track` function

When an OpenTelemetry-instrumented library (for example logfire / PydanticAI) emits spans from inside an `@track`-decorated function, there is no boundary span and no `baggage` to inherit from — `@track` keeps its own context, not an OpenTelemetry one. With `OpikSpanProcessor` registered, those spans are attached to the active `@track` span automatically, producing a single trace instead of a separate synthetic one. No `attach_to_parent` call or header propagation is needed:

```python
import opik
from opentelemetry import trace

tracer = trace.get_tracer("my-service")

@opik.track
def handler(question: str) -> str:
    # Spans started here nest under the `handler` span automatically.
    with tracer.start_as_current_span("retrieve"):
        ...
    return "answer"
```

This is an in-process bridge. The cross-process case (service A → service B) still requires header propagation via `attach_to_parent`, since there is no shared context to read from.

For the full client/server pattern with Python and TypeScript examples, see [Distributed Traces with a Remote Service Using OpenTelemetry](/tracing/advanced/log_distributed_traces#distributed-traces-with-a-remote-service-using-opentelemetry).