json-schema-lookup

# JSON Schema Lookup via SchemaStore Query schemastore.org's catalog of public configuration file schemas to validate structure, discover options, and check allowed values. ## API - **Catalog**: `https://www.schemastore.org/api/json/catalog.json` - Structure: `{ "schemas": [{ "name", "description", "fileMatch", "url", "versions"? }] }` - **Individual schemas**: Fetch the `url` from the matching catalog entry ## Workflow ### 1. Find the schema Search the catalog by name or filename pattern: ```bash # Search by name (case-insensitive) curl -s https://www.schemastore.org/api/json/catalog.json | jq '.schemas[] | select(.name | test("tsconfig"; "i")) | {name, url, fileMatch}' # Search by filename match curl -s https://www.schemastore.org/api/json/catalog.json | jq '.schemas[] | select(.fileMatch[]? | test("package\\.json")) | {name, url}' ``` Alternatively, use WebFetch on the catalog URL and ask for the relevant entry. ### 2. Fetch and inspect the schema ```bash # List top-level properties curl -s SCHEMA_URL | jq '.properties | keys' # Inspect a specific field (type, enum values, description) curl -s SCHEMA_URL | jq '.properties.FIELD_NAME' # Check definitions/shared types (schemas use $ref to these) curl -s SCHEMA_URL | jq '.definitions.DEF_NAME.properties' # Get the full schema (warning - might be large!) curl -s SCHEMA_URL | jq . ``` ### 3. Common queries ```bash # Find enum values for a field curl -s SCHEMA_URL | jq '.properties.FIELD.enum' # List nested properties (e.g. compilerOptions in tsconfig) curl -s SCHEMA_URL | jq '.definitions.compilerOptionsDefinition.properties.compilerOptions.properties | keys' # Find all required fields curl -s SCHEMA_URL | jq '.required' ``` ## Tips - Some schemas use `allOf`/`anyOf` composition -- check those arrays for the full property set - The `versions` field on catalog entries provides version-specific schema URLs when available - Schema URLs vary: some point to `json.schemastore.org`, others to `raw.githubusercontent.com` - For large schemas, query specific paths rather than dumping the entire document - Cache the catalog response locally if making multiple lookups in one session