Skip to main content

Documentation Index

Fetch the complete documentation index at: https://braintrust.dev/docs/llms.txt

Use this file to discover all available pages before exploring further.

Applies to:
  • Plan -
  • Deployment -
Summary When using MCP server with hybrid deployments, authentication may fail with a “data plane mismatch” error because the server connects to the default control plane instead of your organization’s custom data plane URL. This occurs when your organization is configured to use a CloudFront-based data plane endpoint. Configure the MCP server to use your organization’s specific data plane URL found in Settings → Organization → Data plane to resolve the authentication failure.

​
Problem

MCP server authentication fails with data plane mismatch error when your organization uses a custom data plane endpoint.

​
Configuration Steps

​
Step 1: Find your data plane URL

Go to Settings > Data plane and copy the API URL (e.g., https://d8k4dyx7j51un.cloudfront.net).

​
Step 2: Configure MCP server with data plane URL

Remove existing Braintrust MCP configuration and add it with your data plane URL: 
# Remove existing configuration
claude mcp remove braintrust

# Add with data plane URL
claude mcp add --transport http braintrust \
  --header "Authorization: Bearer $YOUR_BRAINTRUST_API_KEY" \
  https://d8k4dyx7j51un.cloudfront.net/mcp

​
Step 3: Verify configuration

Restart Claude and test MCP server connection to confirm it routes to your data plane.

​
Known Limitations

The Braintrust Claude Code plugin does not support custom data plane URLs. Use direct MCP setup as shown above instead of the plugin for hybrid deployments.