MCP Issues

"VULK_API_KEY not set"

The MCP server requires a VULK_API_KEY environment variable. Make sure your editor config includes the env block:

{
  "mcpServers": {
    "vulk": {
      "command": "npx",
      "args": ["-y", "vulk-mcp-server"],
      "env": {
        "VULK_API_KEY": "vk_sk_your_key_here"
      }
    }
  }
}

Get your key from vulk.dev/settings/api-keys.

"Unauthorized" (401) Errors

• Your API key may have been revoked — create a new one in Settings > API Keys
• Verify the key starts with vk_sk_
• Check there are no extra spaces or line breaks in the key

MCP Server Not Starting

Node.js version

Requires Node.js 18 or later. Check with node --version.

npx not found

Ensure npm/npx is installed and in your PATH. Try running npx -y vulk-mcp-server directly in a terminal.

Firewall blocking

The MCP server connects to https://vulk.dev/api/v1/. Ensure outbound HTTPS is allowed.

Tools Not Appearing

After configuring the MCP server, restart your editor completely. Some editors (Claude Desktop, Cursor) need a full restart to pick up new MCP configurations.

Generation Timeout

Large projects may take up to 2 minutes to generate via MCP. If the tool times out, check the project in the VULK web editor — generation may still be running.

Rate Limit Errors

MCP requests follow the same rate limits as the VULK API. If you hit limits, wait for the retryAfter period indicated in the error response.