Atlassian MCP server auto-connects without completing OAuth flow (Sign in button disappears)

Description

The Atlassian MCP server (https://mcp.atlassian.com/v1/mcp) shows a green checkmark (connected) in MCP Settings without completing the OAuth browser flow. No atlassian-* tools are loaded in sessions.

Expected behavior

Clicking 'Sign in' or toggling the server on should open a browser for OAuth authorization (like LeanIX and Lucid do).

Actual behavior

• The 'Sign in' button flashes briefly and disappears
• Green checkmark appears immediately without browser redirect
• No OAuth token is saved (no .tokens.json file in ~/.copilot/mcp-oauth-config/)
• Sessions do not have access to any Atlassian tools

Steps to reproduce

1. Add Atlassian MCP to a plugin .mcp.json:

   "atlassian": { "type": "http", "url": "https://mcp.atlassian.com/v1/mcp" }
   

2. Open MCP Settings
3. Toggle Atlassian on
4. Observe: green checkmark appears without browser opening

Root cause hypothesis

Atlassian MCP endpoint responds to discovery/health-check requests with HTTP 200 without requiring authentication. The app interprets this as 'connected' and skips the OAuth flow. Other MCP servers (LeanIX, Lucid) correctly require auth on these requests.

Workaround

Using Atlassian REST API directly with personal API tokens.

Environment

• Copilot CLI version: 1.0.69
• OS: Windows 11
• Plugin: custom plugin with Atlassian MCP config
• Other MCP servers working correctly: LeanIX, Lucid, QMD (local)

MCP Settings フローと plugin .mcp.json 設定から始め、その後、issue に記載された Atlassian エンドポイントの動作を再現します。検出と認証処理を LeanIX および Lucid と比較します。Sign in で OAuth ブラウザーフローが開き、トークンが保存され、セッションで Atlassian ツールが読み込まれれば完了です。