fix(tracing): Skip child span creation in streaming path when no current span (AI agents)

[sentrivana]

Summary

• When span streaming is enabled and there is no current span, AI agent integrations should not create new root segments for child-span operations
• Adds a sentry_sdk.traces.get_current_span() is None guard before creating spans in the streaming path
• Affected integrations: openai_agents, pydantic_ai

Test plan

• Existing tests pass
• Verify that in streaming mode, no orphan root segments are created for AI agent operations when there's no active span

🤖 Generated with Claude Code

[sentry-warden]

ai_client_span can return None, breaking with ... as span in streaming path

In streaming mode with no current span, ai_client_span now returns None, but callers use it via with ai_client_span(...) as span, which raises AttributeError: __enter__ on None.

Evidence

• ai_client_span sets span = None and only assigns a span when get_current_span() is not None, so it returns None in the guarded streaming case.
• patches/models.py:115 (with ai_client_span(agent, kwargs) as span:) and models.py:154 (with ai_client_span(agent, span_kwargs) as span:) use the return value as a context manager.
• None has no __enter__/__exit__, so entering the with block raises AttributeError before any span logic runs.
• Downstream update_ai_client_span(span, ...) and span.set_attribute in the streaming wrapper also dereference span without a None guard.

Also found at 3 additional locations

• sentry_sdk/integrations/openai_agents/spans/execute_tool.py:23-35
• sentry_sdk/integrations/openai_agents/spans/invoke_agent.py:32-41
• sentry_sdk/integrations/openai_agents/spans/agent_workflow.py:21-28

_{Identified by Warden code-review · P4J-HWE}

[sentry-warden]

ai_client_span can return None but callers use it as a context manager

When streaming is enabled and there is no current span, ai_client_span now returns None, but callers do with ai_client_span(...) as span: (graph_nodes.py:62, 89) and span.__enter__() (init.py), which will raise a TypeError/AttributeError on None.

Evidence

• New span = None branch is returned unchanged when get_current_span() is None.
• graph_nodes.py wraps the result in with ai_client_span(...) as span: (lines 62 and 89); with None raises TypeError: 'NoneType' object does not support the context manager protocol.
• pydantic_ai/__init__.py calls span.__enter__() directly after assigning the return value, which raises AttributeError on None.
• The declared return type Union[Span, StreamedSpan] does not include None, so callers are not prompted to guard against it.

Also found at 2 additional locations

• sentry_sdk/integrations/pydantic_ai/spans/execute_tool.py:71
• sentry_sdk/integrations/pydantic_ai/spans/invoke_agent.py:53-54

_{Identified by Warden code-review · MGK-CD6}

[sentry-warden]

agent_workflow_span can return None, crashing both callers

In streaming mode with no current span this returns None, but callers do with agent_workflow_span(agent) as workflow_span: and workflow_span.__enter__(), both of which raise AttributeError on None.

Evidence

• The new branch sets span = None and only assigns a real span when get_current_span() is not None, so return span can return None.
• runner.py:45 uses with agent_workflow_span(agent) as workflow_span:; entering a with None block raises AttributeError: __enter__.
• runner.py:156-157 does workflow_span = agent_workflow_span(agent) then workflow_span.__enter__(), dereferencing None with no guard.
• Neither caller checks the return value for None before using it.

Also found at 6 additional locations

• sentry_sdk/integrations/openai_agents/spans/ai_client.py:58
• sentry_sdk/integrations/openai_agents/spans/invoke_agent.py:33-41
• sentry_sdk/integrations/pydantic_ai/spans/execute_tool.py:72
• sentry_sdk/integrations/pydantic_ai/spans/invoke_agent.py:53-63
• sentry_sdk/integrations/pydantic_ai/spans/ai_client.py:319
• sentry_sdk/integrations/openai_agents/spans/execute_tool.py:22-22

_{Identified by Warden find-bugs · WP8-UZK}