Missing MCP Notifications/Initialized in Handshake Protocol

Bug Description

MCP Protocol Compliance Bug: Missing notifications/initialized in handshake

Issue:
Claude Code's MCP client doesn't send the required "notifications/initialized" message after the initialize handshake, causing properly-implemented MCP servers to reject tool requests.

Steps to Reproduce:

1. Configure official Roblox MCP server in ~/.config/claude-code/mcp.json
2. Start Claude Code - server shows "connected"
3. Request tools - no Roblox tools available despite connection

Expected Behavior:
After MCP initialize response, Claude Code should send notifications/initialized, then tools should be available.

Actual Behavior:
Claude Code skips notifications/initialized step. Server rejects tool requests with "expect initialized notification" error.

Evidence:
Manual MCP protocol test shows server works correctly:

• echo initialize request → server responds with capabilities
• echo notifications/initialized → server accepts
• echo tools/list → server lists tools

Claude Code only does step 1, missing step 2.

Impact:
Prevents integration with MCP servers that properly implement MCP specification, including official Roblox Studio MCP server.

MCP Server Details:

• Name: Roblox Studio MCP Server (official)
• Protocol: stdio transport
• Version: 0.1.5
• GitHub: https://github.com/Roblox/studio-rust-mcp-server

Environment Info:

• Platform: macOS
• Terminal: VSCode
• Claude Code Version: 1.0.11
• Feedback ID: 9ac74ff8-5920-49a3-82c4-6142e61037b4

Additional Context:
This issue was diagnosed with technical assistance from Claude Desktop, which has working Roblox MCP integration and helped identify the specific MCP protocol compliance problem. The manual protocol testing that revealed the missing notifications/initialized step was performed based on analysis of the MCP specification and comparison with Claude Desktop's working implementation.

Note:
This issue prevents experienced developers from using Claude Code with official, properly-implemented MCP servers for Roblox development workflows.