Use when writing SysML v2 code, asking about "SysML syntax", "naming conventions", "how to write" a part def or calc def, "imports", "syntax error", "parse error", "common mistakes", "pitfalls", "SysML patterns", attribute declarations, units notation, doc comment format, ADR-002, or definition vs usage rules. Provides the canonical syntax rules and patterns for SysML v2 modeling.