Worth noting that "API key access" vs "subscription" has significant cost implications for heavy users.

Claude.ai Pro is $20/month flat. But if you're doing serious agent-assisted coding (multi-file refactors, iterative debugging loops), you can blow through $50-100/day in API costs.

The math changes depending on usage patterns. Subscription makes sense for interactive coding sessions. API keys make sense if you're batch processing or running agents autonomously overnight.