[Bug] Anthropic API Error: False-positive reasoning_extraction safeguard with Workflow tool plugin agentType

Bug Description
▎ False-positive reasoning_extraction safeguard: identical review-panel evaluator prompts (architecture/security/code reviewer charges with a structured-output schema over a facts pack) complete fine as plain agents but are refused with [reasoning_extraction] when dispatched through the Workflow tool with a plugin agentType. Example request id: req_011CeqmCQHEt1zduoksbWuig (2026-09-08). The content is an internal engineering status review of our own codebase; nothing requests model internals. A same-content retry after dropping the agentType field was then flagged as an attempted bypass — which also prevents legitimate A/B isolation of the false positive.

Environment Info

• Platform: darwin
• Terminal: vscode
• Version: 2.1.236
• Feedback ID: 4ff603f6-997e-4605-9da9-92b8e0cb0209

Errors

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