> ## Documentation Index > Fetch the complete documentation index at: https://docs.openlayer.com/llms.txt > Use this file to discover all available pages before exploring further. # Observability > See every gateway request as a trace in your Openlayer project, with no instrumentation Every request through the gateway can be published as a trace in Openlayer, with no code in your apps. It's the visibility side of the gateway: while usage limits and guardrails enforce your rules, observability shows you what actually happened. ## Connect your Openlayer project On the **Config** page, under **Observability**: * Turn observability **on**. * Set the **Openlayer API key env var**, the name of the environment variable holding your Openlayer key (set on the gateway host). * Paste your **inference pipeline ID** from the Openlayer project you want traces to land in. Save, and new requests start showing up as traces in that project. ## What's in a trace Each trace captures the full shape of the request: * The **model** and **provider** that served it. * **Input** messages and the **output** text. * **Tokens**, **latency**, and **cost**. * **Status**, success or error, with the error message when one occurs. * Any **guardrail** violations, as steps in the trace. Every gateway request becomes a trace in Openlayer ## Attribute traffic to a user When an [API key](/gateway/api-keys) is created with a **User ID**, every request it makes carries that ID into the trace. In Openlayer you can then group and filter traffic by user. ## It never blocks a response Tracing is fire-and-forget. The gateway sends each trace in the background after the response has gone out, so observability never slows a request down, and never fails one if Openlayer is unreachable. ## Correlate with your logs Send an `X-Request-ID` header with a request and the gateway uses it as the trace ID, so you can line up your own logs with the trace in Openlayer. Omit it and the gateway generates one. ## Go further Traces are the foundation for Openlayer's monitoring: run tests on your live traffic, track quality over time, and get alerted when something regresses. See the [Observability section](/monitoring/overview) to set that up.