# User Traces
User traces let you stream runtime information—such as generated tokens, intermediate data, or logs—directly into the Midio editor as your application runs. They provide a flexible, customizable way to inspect and visualize what your flow is doing in real time. Unlike standard execution traces, which automatically capture all function calls in a flow and display them in sequence (like a timeline showing the exact order in which functions are invoked), **user traces are explicitly defined by your own code or by libraries you use**. This gives you full control over what gets traced and when. {% hint style="info" %} For a simpler logging method, take a look at the [Log Panel](/midio-docs/reference/overview/log.md) {% endhint %} ## Traces and Spans User traces are **hierarchical**. Each trace can contain one or more **spans**, and spans can themselves contain child traces. This structure allows you to organize and group related operations visually. For example, if you're building an agent that calls multiple tools during execution, you can represent each tool call as a span inside a single trace, or even as a nested child trace. #### Spans A span is a unit of data within a trace. Spans can display various types of information: * Plain text * Structured objects (JSON-like data) * Labeled items (name-value pairs) * And more... You can use spans to display things like: * Prompts sent to an AI model * Responses received from an API * Intermediate steps in a computation Because spans can be nested within traces, they allow you to clearly see how data flows through different stages of a complex operation. ### Streaming from Multiple Processes One of the most powerful features of user traces is that **they can aggregate data from multiple processes into the same trace**. This means you can observe how different concurrent flows interact, or how multiple parallel operations contribute to a single task. For instance, if multiple user requests trigger different processes that all contribute to building an AI response, they can all stream their updates into the same trace. This is especially useful for debugging or understanding asynchronous or agent-like behaviors where work is distributed across many function calls and processes. ## Nodes Some builtin packages, like the LLM package, feed data to the user trace panel. If you want interact with it yourself, you can look at the nodes available in the [`Tracing`](/midio-docs/built-in-nodes/core-std.md#tracing) module. Here is a quick example that starts a new trace, with two child spans.
The above flow does the following: 1. Starts a new trace, with the name `"My Trace"`, which you can see in as the yellow label in the user trace panel. 2. Creates a new text span, as a child of the trace created in **(1)**. 3. Creates another text span, also as a child of the trace created in **(1)**. 4. Finally, we append some more text to the span we created in **(2)**. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.midio.com/midio-docs/reference/overview/user-traces.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.