Capabilities

The MDL language server supports the following LSP capabilities.

Supported Methods

LSP Method	Feature	Notes
`textDocument/publishDiagnostics`	Parse and semantic error reporting	Push-based; parse on change, semantic on save
`textDocument/completion`	Code completion	Keywords, snippets, and project references
`textDocument/hover`	Hover documentation	MDL definitions for qualified names
`textDocument/definition`	Go-to-definition	Opens element source as virtual document
`textDocument/documentSymbol`	Document outline	All MDL statements in the file
`textDocument/foldingRange`	Code folding	Statement blocks, widget trees, comments

Document Synchronization

Method	Supported
`textDocument/didOpen`	Yes
`textDocument/didChange`	Yes (full sync)
`textDocument/didSave`	Yes
`textDocument/didClose`	Yes

Completion Details

Trigger characters: . and (space).

Completion items include:

Keywords – CREATE, SHOW, DESCRIBE, ALTER, DROP, GRANT, etc.
Keyword sequences – PERSISTENT ENTITY, MODULE ROLE, USER ROLE
Data types – String, Integer, Boolean, DateTime, Decimal, etc.
Snippets – Multi-line templates for entity, microflow, page creation
Project references – Module names, entity names, microflow names (requires project)

Diagnostics Details

Parse Diagnostics (on change)

Syntax errors from the ANTLR4 lexer and parser
Missing tokens, unexpected tokens, mismatched brackets
Reported with exact line/column positions

Semantic Diagnostics (on save)

Unresolved entity, microflow, or page references
Invalid attribute names on known entities
Module existence checks
Requires a loaded Mendix project

Not Yet Supported

The following LSP capabilities are not currently implemented:

LSP Method	Status
`textDocument/references`	Planned
`textDocument/rename`	Planned
`textDocument/formatting`	Planned
`textDocument/codeAction`	Planned
`textDocument/signatureHelp`	Not planned
`workspace/symbol`	Not planned