MCP/connectors discovery fails with 403 Forbidden Cloudflare challenge, despite successful ChatGPT login

What version of Codex CLI is running?

codex-cli 0.122.0

What subscription do you have?

ChatGPT Pro

Which model were you using?

gpt-5.4

What platform is your computer?

macOS 26.1 Darwin Kernel Version 25.1.0 arm64

What terminal emulator and version are you using (if applicable)?

zsh shell TERM_PROGRAM / TERM_PROGRAM_VERSION were unset in this session, so the terminal emulator could not be determined programmatically

What issue are you seeing?

Codex CLI/TUI fails to load MCP/connectors discovery data from chatgpt.com backend endpoints.
Requests to discovery-related endpoints return 403 Forbidden with a Cloudflare challenge HTML page instead of JSON.

Observed failing endpoints:

• https://chatgpt.com/backend-api/plugins/featured
• https://chatgpt.com/backend-api//connectors/directory/list?external_logos=true

User-visible impact:

• "failed to load full apps list; falling back to installed apps snapshot"
• "failed to load discoverable tool suggestions"
• MCP/connectors UI appears empty or broken, even though ChatGPT login succeeds

What steps can reproduce the bug?

1. Run codex login
2. Confirm auth succeeds with codex login status -> Logged in using ChatGPT
3. Open Codex and enter a session where apps/connectors/tool suggestions are loaded
4. Observe that apps list / discoverable tool suggestions fail to load
5. Check logs: requests to the endpoints above return 403 Forbidden and the body is a Cloudflare challenge page (`Enable

JavaScript and cookies to continue`)

This machine currently has no user-configured custom MCP servers (codex mcp list returns none), so the failure does not
appear to be caused by a broken local MCP server config.

What is the expected behavior?
After successful ChatGPT login, Codex should be able to fetch discovery data from the backend and load apps/connectors/
discoverable tool suggestions normally, returning JSON rather than a Cloudflare challenge page.

What is the expected behavior?

mcp works normal

Additional information

• Affected account email: miles@... (can provide privately if needed)
• codex login status returns Logged in using ChatGPT
• codex mcp list returns No MCP servers configured yet
• Local config does not contain any [mcp_servers.*] entries; only the Figma plugin is enabled
• The response body is clearly a Cloudflare challenge page, including Enable JavaScript and cookies to continue
• Example cf-ray values seen in logs:
• 9f0606eaaa5c17fe
• 9f060859edadd301
• 9f06085a19f84855
• Internal RMCP initialization still succeeds for codex-connectors-mcp, which suggests local MCP transport is alive and

the failure is specifically on the remote discovery path

• This may be related to other Cloudflare / bot-detection / TLS-fingerprint style 403 reports, but local evidence only

proves the discovery requests are being challenged