Google Antigravity cannot communicate with Ark MCP server

[ndac-todoroki]

Description

Ark MCP in Google Antigravity leads to a startup error.

What's happening

Antigravity picks up stdout (console.info) at the startup of Ark MCP and raises an error.

As I tested in local, changing to console.error fixes it.

Link to Reproduction (or Detailed Explanation)

(I posted screenshot in the description)

Steps to Reproduce

1. Setting up a MCP server in Google Antigravity is done like this:

// mcp_config.json
{
    "mcpServers": {
        "ark-ui": {
            "command": "npx",
            "args": [
                "-y",
                "@ark-ui/mcp"
            ]
        }
    }
}

2. go to "Manage MCP servers" page
3. "Refresh" at the top-right
4. ark mcp logs an error.

Ark UI Version

5.19.1

Framework

• React
• Solid
• Vue
• Svelte

Browser

No response

Additional Information

Other examples:

• https://github.com/modelcontextprotocol/servers/blob/main/src/sequentialthinking/index.ts#L112C3-L112C68 uses console.error
• https://github.com/hypothesi/mcp-server-tauri/blob/079168508207a6bd5a007520cf84106a4f63e5e2/packages/mcp-server/src/index.ts#L158-L164 avoids showing messages at startup