The supervisor selected strict startup registration with a shared isFirstSync flag. Because the MCP SDK may deliver tools/list_changed before connect() resolves, that notification could enter the sync queue first, consume the strict option inside its contained handler, and leave the actual activation sync non-fatal.
Pass startup intent explicitly to connectGeneration(). Only the plugin activation attempt receives the failOnStartupError registration policy; notification-driven syncs and later reconnect generations always use contained runtime semantics. Queue arrival order can no longer redefine startup behavior.
A regression test injects list_changed from inside connect(), keeps a foreign namespace squatter in place, and proves activation still rejects after the notification's contained sync. Focused package coverage remains 100%, and the bilingual reconnect note records the ownership rule.
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