Configuration

All settings are in the jsonschema namespace and can be set in User, Workspace, or Folder settings.

---

jsonschema.preview.autoOpen

Type	Default
boolean	false

When true, the preview panel opens automatically whenever a JSON Schema file becomes the active editor (on file open or tab switch). Silently skipped in untrusted workspaces.

// .vscode/settings.json
{
  "jsonschema.preview.autoOpen": true
}

---

jsonschema.preview.liveUpdate

Type	Default
boolean	false

When true, the preview refreshes as you type (debounced). The preview panel must already be open — live update does not auto-open the panel. Skipped in untrusted workspaces.

{
  "jsonschema.preview.liveUpdate": true
}

---

jsonschema.preview.liveUpdateDelay

Type	Default	Minimum
number (ms)	1500	500

Milliseconds to wait after the last keystroke before the live preview refreshes. Increase this value on slower machines.

{
  "jsonschema.preview.liveUpdateDelay": 800
}

---

jsonschema.preview.renderer

Type	Default	Values
string	"auto"	"auto", "builtin"

Which engine renders the schema preview:

• auto — use the richer json-schema-for-humans (Python) output when it is available, and fall back to the extension's built-in renderer otherwise.
• builtin — always use the built-in, dependency-free renderer and never invoke Python. Choose this if you don't have (or don't want) a Python interpreter: the preview appears immediately with no interpreter probe or install prompt.

{
  "jsonschema.preview.renderer": "builtin"
}

---

jsonschema.preview.renderTimeout

Type	Default	Minimum
number (ms)	30000	1000

Milliseconds to wait for the json-schema-for-humans render subprocess before it is killed and an error page (with a timeout hint) is shown instead. Values below the minimum are clamped.

{
  "jsonschema.preview.renderTimeout": 60000
}

---

jsonschema.remoteFetchTimeout

Type	Default	Minimum
number (ms)	30000	1000

Milliseconds to wait for any outbound remote-schema HTTP request — authentication fetches, schema caching, and catalog lookups all share this timeout — before it is aborted.

{
  "jsonschema.remoteFetchTimeout": 15000
}

---

jsonschema.workspaceValidation.maxFiles

Type	Default	Minimum
number	2000	1

Maximum number of files the JSON Schema: Validate Workspace command scans in one run. When the workspace has more matching files than this, the run is truncated and the summary report notes it. Discovery already honours files.exclude / search.exclude and skips files over 1 MiB; this cap bounds the total regardless.

{
  "jsonschema.workspaceValidation.maxFiles": 5000
}

---

jsonschema.cache.autoRefresh

Type	Default	Values
string	"off"	off, onOpen, daily

Automatically revalidates a locally cached schema against its origin using conditional (ETag / Last-Modified) requests. off never revalidates automatically; onOpen revalidates a schema at most once per session when a bound file becomes the active editor; daily revalidates at most once every 24 hours. A 304 Not Modified response leaves the cache untouched, and a failed revalidation is silent — the stale cached copy keeps serving IntelliSense.

{
  "jsonschema.cache.autoRefresh": "onOpen"
}

---

jsonschema.catalog.useSchemaStore

Type	Default
boolean	true

Includes the public SchemaStore catalog in the Bind Schema… → Browse catalog… picker.

jsonschema.catalog.sources

Type	Default
array of string	[]

Additional schema-catalog URLs in the SchemaStore catalog format ({ "schemas": [{ "name", "description", "url", "fileMatch" }] }). Private catalogs are fetched with the credentials configured via Configure Schema Authentication….

{
  "jsonschema.catalog.sources": ["https://internal.example.com/schema-catalog.json"]
}

The Browse catalog… picker (opened from Bind Schema…) is filterable by schema name and description, and shows the source catalog and URL as each entry's detail. Entries whose fileMatch glob matches the file you're binding are ranked first, under a "Suggested for this file" separator. Fetched catalogs are cached for 24 hours in global storage — reopening the picker within that window never hits the network — and if a refetch fails and a cached copy exists, the picker falls back to it and marks the title as offline/stale rather than failing outright.

---

jsonschema.lint.enabled

Type	Default
boolean	true

Reports schema-quality diagnostics — missing description/$schema, unknown keywords, duplicate enums, and similar — on JSON Schema files, in a dedicated Problems-panel source separate from data-file validation.

jsonschema.lint.rules

Type	Default
object	{}

Per-rule severity overrides. Map a rule id to off, hint, info, or warning. Rule ids: no-unknown-keywords, require-schema-declaration, require-root-id, require-descriptions, explicit-additional-properties, no-duplicate-enum, no-empty-required.

{
  "jsonschema.lint.rules": {
    "require-descriptions": "off",
    "no-unknown-keywords": "warning"
  }
}

---

.json-schema-preview-config.json

The extension discovers a .json-schema-preview-config.json file in the workspace folder that contains the schema being rendered (with fallback to other workspace folders in order). The file controls the json-schema-for-humans renderer and the output template.

Example:

{
  "template_name": "js",
  "show_toc": true
}

All json-schema-for-humans options are supported. Create or edit the file via JSON Schema: Configure Preview (visual UI) or JSON Schema: Open Config File (opens the raw JSON).

Output templates

The template_name field controls the rendered format:

Value	Output	Notes
flat	HTML	Default when no config file is present
js	HTML	JavaScript-style collapsible tree
md	Markdown	Markdown table; displayed as raw source in VS Code, downloadable as .md
md_nested	Markdown	Nested Markdown structure
rst	reStructuredText	Plain text display
html	Standalone HTML	Self-contained file with embedded styles

The Download button in the preview panel uses the correct extension (.html or .md) based on the active template.

---

Schema Binding (json.schemas / yaml.schemas)

Schema bindings created via Bind Schema… are written to VS Code's standard json.schemas (for JSON/JSONC/JSONL files) and yaml.schemas (for YAML files) settings, or inline as the file's own $schema field. Choose the scope when prompted:

Scope	Stored in	Lifetime
Workspace file	.code-workspace file	Committed with the repo (multi-root workspaces only)
Workspace folder	.vscode/settings.json	Committed with the repo
User	User settings.json	All workspaces on this machine
Inline ($schema field)	The data file itself	Portable to other editors and tools

Bindings can be edited manually in the relevant settings.json file. TOML files use the inline scope exclusively — VS Code has no built-in toml.schemas mechanism, so the picker offers only the inline option for .toml files.

For a fresh inline binding on a YAML file, the extension picks the notation automatically: if the Red Hat YAML extension is installed it writes a # yaml-language-server: $schema=... comment directive, otherwise a plain $schema: key. If the file already has either form, that existing form is always updated in place — the extension never switches a file from one notation to the other.

TOML Schema IntelliSense

While VS Code's own language servers provide schema-driven editing help for JSON and YAML, TOML has no schema-aware language server — so this extension fills the gap itself. In any .toml file with an inline "$schema" binding you get:

• Key completions from the schema's properties, scoped to the current [table] / [[array-of-tables]] header and dotted-key path. Keys already present in the table are omitted; schema-required keys sort first and are marked (required).
• Value completions after = for enum/const alternatives and booleans, serialised as valid TOML (quoted strings, bare numbers).
• Hover documentation on keys showing the schema's title, type, description, enum values, and numeric bounds.

Schema $refs are followed (local pointers, files next to the schema, cached remote schemas). Everything works offline: a remote schema is read from the local cache — run JSON Schema: Cache Schema Locally once to populate it — and no request is ever made while you type. Removing the $schema line turns the assistance off.