Build a Claude Opus 5 Token Economics MCP Server for Real-Time Cost Optimization
Claude Opus 5 costs $5/$25 per million input/output tokens — the same as Opus 4.x but approaching Fable 5 capabilities at half the cost. This FastMCP server tracks real-time token spend, enforces per-session budget gates, and auto-routes to Sonnet 5 when thresholds are breached.