[BUG] claude.ai Slack MCP connector not available in Claude Code despite being connected in web settings

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

The list of claude.ai MCP connectors available in Claude Code does not match the connectors shown as connected on the claude.ai web settings page. Specifically, the Slack connector shows as connected
and authorized in claude.ai web settings but does not appear in Claude Code. Other connectors (Atlassian, Figma, Google Calendar, Microsoft 365, Miro) are available.

This began after a Claude.ai service outage on 2026-04-06. All connectors disconnected during the outage. After the outage resolved, all connectors except Slack reconnected.

Environment

• Claude Code version: 2.1.92 (latest)
• OS: macOS (Darwin 24.4.0, arm64)
• Shell: zsh
• Behind corporate proxy with NODE_EXTRA_CA_CERTS configured
• Claude Desktop app: 1.569.0

What Should Happen?

Expected Behavior

All connectors that are connected and authorized in claude.ai web settings should appear as available MCP servers in Claude Code after login/restart. The connector list should be in sync.

Actual Behavior

• claude.ai web settings shows Slack as connected
• Claude Code does not show Slack as an available MCP server
• Other claude.ai connectors (Atlassian, Figma, Google Calendar, Microsoft 365, Miro) ARE available in Claude Code
• The mismatch persists across multiple restarts and re-authentication attempts

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce

1. Have claude.ai Slack connector previously working in Claude Code (tools like mcp__claude_ai_Slack__slack_send_message available)
2. Experience a claude.ai service disruption that disconnects all cloud MCP connectors
3. After service recovers, observe that some connectors reconnect but Slack does not
4. Go to claude.ai/settings → Connectors/Integrations → verify Slack shows as connected
5. In Claude Code, run /login (succeeds)
6. In Claude Code, run /mcp — Slack is not listed among available claude.ai servers
7. Disconnect and reconnect Slack in claude.ai web settings
8. Restart Claude Code (claude -c)
9. Run /mcp again — Slack still not available

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

v2.1.92

Claude Code Version

v2.1.92

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

IntelliJ IDEA terminal

Additional Information

_No response_