MCP asks RW grants for RO access

[4ertus2]

Describe the bug

MCP with GITHUB_PERSONAL_ACCESS_TOKEN and GITHUB_READ_ONLY asks for auth with lots of write rights.

Affected version

GitHub MCP Server
Version: v1.5.0
Commit: 8cd03c0
Build Date: 2026-06-27T07:57:40Z

Steps to reproduce the behavior

1. Create GITHUB_PERSONAL_ACCESS_TOKEN with RO-access grants
2. Run MCP from qwen-code with such configuration

  "mcpServers": {
    "github": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "ghcr.io/github/github-mcp-server"
      ],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "github_pat_...",
        "GITHUB_READ_ONLY": 1
      }
    }
  },

3. Asks to show your open issues on github
4. Find that additional MCP auth needed with lots of unwanted grants asked

   ✓ get_me (github MCP Server) {}
     Visit https://github.com/login/device and enter the code XXXX-XXXX to authorize the GitHub MCP Server.

     After authorizing, retry your request.

Expected vs actual behavior

1. MCP use just the grants it could get from GITHUB_PERSONAL_ACCESS_TOKEN
2. No additional authentication needed
3. MCP disallow comands that need more grants that MCP has. Without attemps to get additional ones.

Logs