HTTP MCP server with OAuth: "Got new credentials, but reconnecting failed" — server never connects

Describe the bug

When an HTTP MCP server requires OAuth (using the standard WWW-Authenticate: Bearer + OAuth protected resource metadata flow), Claude Code successfully completes the OAuth authorization and reports "Got new credentials, but reconnecting to <server> failed. Restart Claude Code to retry." However, restarting does not help — the server remains disconnected and continues returning 401.

Steps to reproduce

1. Add an HTTP MCP server that requires OAuth to a project in ~/.claude.json:

``json
"indeed": {
"type": "http",
"url": "https://mcp.indeed.com/claude/mcp"
}
``

1. Run /mcp and select "Authenticate" for the server
2. Complete the OAuth flow in the browser (redirect to localhost callback succeeds)
3. Claude Code shows: "Got new credentials, but reconnecting to indeed failed. Restart Claude Code to retry."
4. Restart Claude Code — server still shows as unauthenticated / returns 401

Expected behavior

After completing OAuth, the server should connect successfully and its tools should be available.

Environment

• Claude Code version: 2.1.128
• OS: macOS 25.4.0
• MCP server: https://mcp.indeed.com/claude/mcp (OAuth via https://secure.indeed.com/)