HCL Schema for VS Code

Validation, completion and hover for HCL files described by a *.schema.hcl schema.

What it does

Add a __schema attribute to an HCL file:

__schema = "./service.schema.hcl"

name = "checkout"

listener "https" {
  port = 443
}

and the extension gives you, against that schema:

Diagnostics as you type, on the unsaved buffer
Completion of declared attributes and blocks, and of an attribute's permitted values
Hover documentation written once in the schema's description
Go to definition from a use to its declaration in the schema
A document outline

Screenshot

Setting	Default	Meaning
`hclSchema.cliPath`	`""`	Path to the `hclschema` binary. Empty uses the bundled one.
`hclSchema.strict`	`false`	Apply draft 2026-09 rules to schemas that pin an older draft
`hclSchema.offline`	`false`	Never fetch remote schemas; use the cache only
`hclSchema.cacheDir`	`""`	Where cached remote schemas live

None. The binary for your platform ships with the extension. The HashiCorp HCL extension is installed alongside it for syntax highlighting.

MIT.