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Propagates parent attributes via CoreFiddlerSpanProcessor plus Strands-specific behavior. On every span start this processor:
  1. Delegates to CoreFiddlerSpanProcessor for standard attribute denormalization.
  2. For chat spans only: copies the parent’s system_prompt into a gen_ai.system.message event as a workaround for Strands not always emitting that event on the chat span upstream (strands-agents/sdk-python#822).

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on_start()

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

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Parameters

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span
Span
required
The span being started.
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parent_context
Context | None
default:"None"
The parent context, if any.