This repository provides `claude-monitor`, a privacy-first CLI application for real-time monitoring of Claude Code usage. It reads local JSONL session logs, computes token consumption, costs, and burn rates, and displays them via a Rich-based terminal UI. The tool supports multiple subscription plans (Pro, Max5, Max20, Custom), integrates with Claude Code's official rate limits via statusline capture, and offers an opt-in persistent usage warehouse for historical analysis. It is distributed as a PyPI package with command aliases `cmonitor` and `ccm`. The architecture is modular, with separate packages for CLI, core logic, data ingestion/analysis, monitoring, output formatting, terminal management, UI components, and utilities. Key entry points include the CLI main module (`cli/main.py`), snapshot builder (`output/snapshots.py`), and monitoring orchestrator (`monitoring/orchestrator.py`). The application is well-tested with over 700 tests covering snapshot, trust-layer, warehouse, UI, timezone, and CLI paths. While primarily an application, it incorporates data engineering patterns such as sessionization, percentile-based limit estimation, and a versioned JSON warehouse. The codebase demonstrates strong craftsmanship with reusable components like the P90Calculator, PricingCalculator, TimezoneHandler, and UsageWarehouse. However, it has some technical drift risks due to hardcoded pricing rates, dependency on Claude Code's internal log format, and experimental API features that may change.