Together AI provides fast inference for a wide range of open-source models. The Together and AsyncTogether chat completions clients can be instrumented using the openinference-instrumentation-together package, which traces calls as OpenInference LLM spans.
This integration requires together >= 2.0.0.
Install#
Setup#
Set the TOGETHER_API_KEY environment variable to authenticate calls made using the SDK.
Connect your application to Phoenix with the register function:
auto_instrument=True picks up the installed openinference-instrumentation-together package automatically. To instrument explicitly instead, call TogetherInstrumentor().instrument(tracer_provider=tracer_provider).
Run Together AI#
A simple chat completion that is now instrumented:
Streaming#
When stream=True, the span stays open until the stream is fully consumed, then records the accumulated output, tool calls, and token counts from the chunks.
Tool calls#
Tools passed on the request (llm.tools.*) and any tool calls returned on the response (message.tool_calls.*) are captured on the span.
Observe#
Now that you have tracing setup, all invocations of Together AI chat completions (sync and async, streaming and non-streaming) will be streamed to your running Phoenix for observability and evaluation.

