[BUG] claude.ai visualize feature broken — claudemcpcontent.com unreachable (DNS_PROBE_FINISHED_NXDOMAIN) --- PLEASE REVIEW!

[mandilorian]

Preflight Checklist

• I have searched existing issues and this hasn't been reported yet
• This is a single bug report (please file separate reports for different bugs)
• I am using the latest version of Claude Code

What's Wrong?

When using claude.ai, any response that uses the visualize feature fails with: "Failed to set up MCP app for 'visualize'. Check that claudemcpcontent.com is not blocked by your network or browser."

The domain claudemcpcontent.com returns DNS_PROBE_FINISHED_NXDOMAIN and cannot be reached by any browser.

This is not a user-side network issue — DNS was changed to Cloudflare 1.1.1.1 with no change in behavior.

OS: Windows 11 Home.

What Should Happen?

The visualize feature in claude.ai should render interactive charts, diagrams, and widgets inline in the chat. The domain claudemcpcontent.com should be reachable and the MCP app should initialize successfully.

Error Messages/Logs

Failed to set up MCP app for "visualize". Check that claudemcpcontent.com is not blocked by your network or browser.
Browser check: navigating directly to https://claudemcpcontent.com returns DNS_PROBE_FINISHED_NXDOMAIN — the domain does not resolve at all. Tested with both Verizon default DNS and Cloudflare 1.1.1.1 / 1.0.0.1 with identical results.

Steps to Reproduce

1. Open claude.ai in a browser
2. Start any conversation that triggers the visualize feature (e.g. ask Claude to create a chart or diagram)
3. Observe the error pop-up: "Failed to set up MCP app for 'visualize'"
4. No workaround exists — persists across browser restarts, DNS changes, and network troubleshooting

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

No response

Claude Code Version

N/A — this issue occurs on claude.ai in the browser, not Claude Code CLI.

Platform

Other

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

This is a claude.ai browser issue, not a Claude Code CLI issue — the bug report form doesn't perfectly fit.

OS: Windows 11 Home.

Browser tested: Chrome.

DNS tested: Verizon default and Cloudflare 1.1.1.1 — domain unreachable on both.

The visualize feature has never worked. No browser extensions blocking the domain were found.

Other claude.ai features work normally.

[mandilorian]

This was filed using the Claude Code form because no claude.ai-specific form exists, but this bug occurs in the claude.ai web browser interface, not Claude Code CLI. Please re-evaluate — the visualize MCP feature is broken for browser users and claudemcpcontent.com is unresolvable. This is a valid bug report.

[RizzKat]

I have the same issue Failed to set up MCP app for "visualize" Check that claudemcpcontent.com is not blocked by your network or browser

[AAACrazyMonkey]

‘Same issue happened to me as well. "Failed to set up MCP app for "visualize". Check that claudemcpcontent.com is not blocked by your network or web browser". Not sure how to solve it.....

[wjtang123]

Same issue to me! This is a valid bug! Please fix it...

[jectpro7]

same issue

[RubenPX]

Same issue

[ualtinok]

+1

[tobydz]

I have the same issue with the latest version of the Claude App on MacOS (latest build).

[TangVarie]

The same problem is intermittent and keeps recurring.

[mandilorian]

Update: the issue is now affecting the Figma MCP connector as well, with the identical error: 'Failed to set up MCP app for Figma. Check that claudemcpcontent.com is not blocked by your network or browser.' This confirms the problem is with claudemcpcontent.com infrastructure broadly, not just the visualize feature.

[Lzhtommy]

when i ask claude (web and app) to create a diagram, the same problem occur