Codex MCP connections fail with 403 on '/wham/tasks/list' and '/wham/environments' (VSCode/Windsurf)

What version of the IDE extension are you using?

0.4.76

What subscription do you have?

Enterprise

Which IDE are you using?

VS Code, Windsurf

What platform is your computer?

macOS

What issue are you seeing?

Facing issues accessing MCP servers via the Codex extension on MacOS, even though the configuration matches the official MCP setup guide.

Environment Details:
OS: MacOS
VSCode Version: 1.109.5
Codex Extension Version: (latest – recently installed)
Model: gpt-5.3-codex

Version of current config.toml:

model = "gpt-5.3-codex"
model_reasoning_effort = "medium"
approval_policy = "on-request"
sandbox_mode = "workspace-write"
[mcp_servers.sample]
command = "npx"
startup_timeout_sec = 60
args = [
  "mcp-remote",
  "{INTERNAL_LINK}",
  "--allow-http"
]
env = { }

(We also previously tested with the Atlassian MCP configuration as per documentation, but encountered the same issue.)

Key Error Logs:

[error] Error fetching httpStatus=403 statusText=Forbidden url=/wham/tasks/list?limit=20&task_filter=current
[error] Error fetching httpStatus=403 statusText=Forbidden url=/wham/environments
[warning] codex_rmcp_client::rmcp_client: Failed to terminate MCP process group: Operation not permitted (os error 1)
[warning] Model personality requested but model_messages is missing, falling back to base instructions.

We have:

• Restarted VSCode
• Updated config per recommendations
• Removed trust_level="trusted" and switched to approval_policy="on-request"
• Tested both Windsurf IDE and VSCode

Could you please help us identify whether this could be:

• An MDM-managed configuration issue?
• An internal, company access/IIQ permission issue?
• A Mac-specific Codex extension issue?

Happy to share full logs if needed.

What steps can reproduce the bug?

1. Ensure latest Codex extension and VSC/Windsurf versions are used.
2. Set up config.toml as per the documentation/instructions.
3. Reload the window.

What is the expected behavior?

The Auth Sign-in window should popup for setting up the MCP server.

Additional information

_No response_