[BUG] MCP OAuth support for HTTP servers (e.g. Atlassian official MCP)

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?

Problem

Claude Code does not support OAuth authentication flows for HTTP MCP servers.
The official Atlassian MCP (https://mcp.atlassian.com/v1/mcp) requires OAuth,
which VS Code Copilot handles natively but Claude Code does not.

What Should Happen?

Expected behavior

Claude Code should support OAuth flows for HTTP MCP servers, similar to how
VS Code handles them natively.

Error Messages/Logs

No project could be found with key 'CCV'.
You do not have permission to create issues in this project.

Steps to Reproduce

1. Add the official Atlassian MCP to .mcp.json:

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

1. Restart Claude Code — no OAuth prompt appears, tools fail to load

1. As workaround, use community mcp-atlassian via uvx with API token
2. API token auth works for classic Jira Software projects but fails for Jira Product Discovery projects with "No project could be found"

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Using Claude Code VS Code extension

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Impact

Users cannot use the official Atlassian MCP with Claude Code, and are limited
to community alternatives (mcp-atlassian via API token) that don't support
all Jira project types (e.g. Jira Product Discovery).