Add support for custom Anthropic API URL

[saxyguy81]

Summary

This PR adds support for custom Anthropic API URLs, allowing users to use local proxies or custom API endpoints for development and testing.

Changes

• ✨ New configuration setting: superdesign.anthropicUrl
• 🔧 Updated customAgentService.ts to support custom URLs
• 🛡️ Conditional Helicone header inclusion (only for default URL)

Use Cases

1. Local Development - Use with ccproxy-api or similar local Claude API proxies
2. Testing - Test with custom API endpoints
3. Debugging - Monitor API calls through local proxy
4. Alternative Tracking - Use different analytics/tracking services

How It Works

Configuration

Users can add to their VS Code settings:

{
  "superdesign.anthropicUrl": "http://localhost:4000"
}

Behavior

• Without custom URL: Uses default https://anthropic.helicone.ai/v1 with Helicone headers
• With custom URL: Uses specified URL without Helicone headers (assumes custom proxy handles its own auth/tracking)

Implementation Details

• Read anthropicUrl from workspace configuration
• Conditionally construct createAnthropic options based on presence of custom URL
• Log custom URL usage for debugging
• No breaking changes - fully backward compatible

Code Changes

package.json:

• Added superdesign.anthropicUrl configuration property

src/services/customAgentService.ts:

• Read custom URL from config
• Use custom URL if provided, otherwise default to Helicone
• Conditionally include Helicone auth headers only when using default endpoint
• Added logging for custom URL usage

Testing

✅ TypeScript compilation passes
✅ Backward compatible (no custom URL = existing behavior)
✅ Code follows existing patterns
⏳ Manual testing with local proxy recommended

Benefits

• Enables use of local Claude API proxies like ccproxy-api
• Allows testing with custom endpoints
• Provides flexibility for different deployment scenarios
• Maintains full backward compatibility

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🤖 Generated with Claude Code

Co-Authored-By: Claude Sonnet 4.5 noreply@anthropic.com