Each state has its own valid operations. Out-of-order causes errors.

What you're seeing

States: spawned (process running, not initialized), initialized (capabilities agreed), serving (handling requests), shutdown. Out-of-order: send tools/call before initialize → error.

★ KEY TAKEAWAY
MCP server states: dead → spawned → initialized → serving → shutdown. Out-of-order operations error.
▶ WHAT TO TRY
  • Try clicking Call before Init — gets rejected.
  • Walk through the correct sequence.
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