If you've been trying to connect the NetSuite AI Connector to Claude Code and hitting a wall, you're not alone. There's a known bug that prevents OAuth authentication from completing—and unfortunately, there's no workaround at this time.

The Problem

When you add the NetSuite MCP server to Claude Code and attempt to authenticate, the process fails before a browser window ever opens. You'll see errors like this in your logs: 

[DEBUG] MCP server "netsuite": No client info found
[DEBUG] MCP server "netsuite": SDK auth error: Le
[ERROR] MCP server "netsuite" Connection failed

The frustrating part? The exact same NetSuite MCP server works perfectly in Claude Desktop and Claude.ai.

What's Happening

The issue lies in how Claude Code handles OAuth metadata from the NetSuite MCP server:

  1. Claude Code successfully connects to the NetSuite MCP server
  2. It retrieves the OAuth metadata (including the mcp scope)
  3. It fails to parse the client credentials from that metadata
  4. Without client credentials, it can't generate the authorization URL
  5. The browser never opens, and authentication fails

Claude Desktop's OAuth parsing logic handles this correctly. Claude Code's parsing logic has a bug or incompatibility.

The Workarounds

Until Anthropic fixes this bug, you have two options:

Option 1: Use Claude Desktop

If you need MCP access to NetSuite from a desktop application, Claude Desktop works. Add the same MCP server configuration there and the OAuth flow will complete normally.

Option 2: Use Claude.ai (Web)

The web-based Claude.ai handles NetSuite connectors correctly:

  1. Go to Settings > Connectors
  2. Click Add custom connector
  3. Enter your NetSuite MCP URL (e.g., https://[accountid].suitetalk.api.netsuite.com/services/mcp/v1/all)
  4. Complete the OAuth flow in your browser

This works because Claude.ai's connector system handles OAuth differently than Claude Code's CLI-based approach.

Tracking the Fix

This issue has been reported to Anthropic as GitHub Issue #11862. It's tagged as a bug affecting the area:auth and area:mcp components.

If this is blocking your work, consider adding a thumbs-up to the issue to help prioritize it.

The Bottom Line

NetSuite's MCP integration is powerful—when it works. For now, Claude Code users will need to use Claude Desktop or Claude.ai for NetSuite access. Hopefully, Anthropic will ship a fix soon.