> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fiddler.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# FiddlerSpanProcessor

> Span processor that automatically propagates attributes from parent to child spans.

Span processor that automatically propagates attributes from parent to child spans.

## DENORMALIZED\_ATTRIBUTES

## on\_start()

Called when a span starts. Automatically propagates attributes from parent.

### Parameters

<ParamField path="span" type="Span" required={true}>
  The span being started.
</ParamField>

<ParamField path="parent_context" type="Context | None" required={false} default="None">
  The parent context, if any.
</ParamField>

## force\_flush()

No buffered state; satisfy `SpanProcessor` interface.

### Returns

`bool`