Why do Cursor and Claude Code both say connected to my memory server and still share nothing?

Developers often encounter a frustrating issue where multiple AI coding editors, such as Cursor and Claude Code, report a successful connection to a shared memory server while failing to actually sync data. The author, a contributor to the Mnemoverse project, explains that a 'healthy connection' only confirms the transport layer is active, not that the data is being shared across accounts or workspaces. Through an analysis of seven memory systems—including Mem0, Cognee, Supermemory, Letta, and Zep—the article demonstrates that isolation often occurs due to misconfigured identifiers, separate API keys, or differing repository tags. The author emphasizes that developers should not rely on connection status indicators alone. Instead, the only reliable way to verify cross-editor memory sharing is to perform a manual test: write a specific marker in one editor and confirm its visibility in the other.