fix: correct concurrent subagent trace parenting#302
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lgtm! just a couple small non-blocking nits but 🚢
When Claude Code spawns multiple concurrent subagents (parallel Task tool calls), the LIFO agent_span_stack caused spans to get parented to the wrong subagent. Fix by using the parent_id captured at PreToolUse time, tracking LLM-to-agent mappings in the link tracker, and adding prompt-based agent matching for first LLM calls. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…_prompt Address review nit — build request_text via direct string concatenation instead of accumulating into a list and joining. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
agent_span_stackcaused spans to get parented to the wrong subagentactive_agentsdict to SessionState for concurrent subagent resolutiontest_concurrent_subagents_parent_correctlyTest plan
Claude session:
290749d0-c759-42b7-8d1b-d4edb76c65d3Resume:
claude --resume 290749d0-c759-42b7-8d1b-d4edb76c65d3🤖 Generated with Claude Code