After investigating a billing dispute for more than 25 turns, you determine that duplicate charges...

Option C gives the human agent the operational state required to continue without replaying a long conversation. The handoff should include verified identifiers, the duplicate transaction evidence, the diagnosed timeout-and-retry mechanism, the $847 refund requirement, the agent’s $500 authorization constraint, completed verification steps, prior actions, and the recommended resolution. Any unresolved uncertainty should be labeled explicitly.

Anthropic’s effective context-engineering guidance recommends preserving high-value state in structured notes while removing redundant conversational and tool-call history. Its long-running-agent guidance likewise describes structured handoffs as the mechanism for maintaining continuity across context resets or agent boundaries.

Option A maximizes raw information but forces the human to locate the relevant facts among more than 25 turns, increasing delay and error risk. Option B preserves evidence but omits the authorization constraint, completed verification, and explicit recommended action. Option D is too sparse to support validation or execution. A structured handoff balances fidelity and efficiency: it contains everything needed for the next actor to make the refund decision while excluding greetings, repeated explanations, and irrelevant intermediate tool output.

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