Understand vs Universal Ctags

Understand is a static analysis and code-comprehension tool from SciTools. It builds a cross-referenced model of source code without executing it, then helps users explore relationships through its Information Browser, call trees, dependency analysis, and visual graphs, including butterfly and control-flow views. It also provides metrics, CodeCheck, version comparison, APIs, a command-line interface, and AI chat. Supported languages include C/C++, C#, Fortran, Java, Python, Rust, VHDL, Visual Basic, and web languages such as HTML, CSS, JavaScript, TypeScript, PHP, and XML. It runs on Windows 11, specified Linux distributions, and macOS Monterey or later; command-line automation, CI, and an official Docker image are also available. The VS Code extension is separately licensed. Local AI keeps code and prompts on the user's hardware, while cloud AI sends requests with code context to the selected provider. Offline use is supported with offline licensing. Pricing includes a free plan and paid subscriptions from $100/user/mo (annual).

Universal Ctags has no write-up on Specifiction yet; its figures are above.