langium

Build, fix, and improve Langium 4.x languages. Recipes, best practices, and troubleshooting for .langium grammars, scoping and cross-references, validation, LSP features (formatting, semantic tokens, code actions, hover, completion), code generators, langium/test tests, langium-config.json, and multi-language projects. Use when working in any project that depends on langium or langium-cli, or when a Langium language misbehaves (parse errors, unresolved references, missing diagnostics or editor features).