MCP_SESSION_ID is improperly named

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ファイル、テスト、エントリーポイント、環境、再現手順、または想定される命名は提供されていません。まずリポジトリと既存の issue で MCP_SESSION_ID への参照を検索し、その後、意図された名前と影響を受ける使用箇所を明確にしてください。命名の不一致が再現され、想定される識別子が確認され、関連するテストがパスすれば完了です。