schema-gen-mcp

Instructions

Implementation Reference

• mcp-server/src/index.ts:324-375 (handler)

  The 'validateSchema' function implements the validation logic for the 'validate_schema' tool, checking for JSON format, '@context', '@type', and type-specific fields.

  function validateSchema(jsonString: string): {
    valid: boolean;
    errors: string[];
    warnings: string[];
  } {
    const errors: string[] = [];
    const warnings: string[] = [];
  
    let parsed: unknown;
    try {
      parsed = JSON.parse(jsonString);
    } catch {
      return {
        valid: false,
        errors: ["Invalid JSON: unable to parse the provided string"],
        warnings: [],
      };
    }
  
    if (typeof parsed !== "object" || parsed === null || Array.isArray(parsed)) {
      return {
        valid: false,
        errors: ["JSON-LD must be a JSON object (not an array or primitive)"],
        warnings: [],
      };
    }
  
    const schema = parsed as Record<string, unknown>;
  
    if (!schema["@context"]) {
      errors.push('Missing required field: @context (should be "https://schema.org")');
    } else if (schema["@context"] !== "https://schema.org") {
      warnings.push(
        `@context is "${schema["@context"]}" — recommended value is "https://schema.org"`
      );
    }
  
    if (!schema["@type"]) {
      errors.push("Missing required field: @type");
    } else {
      const type = schema["@type"] as string;
      const supportedTypes = Object.keys(SCHEMA_TYPES);
      if (!supportedTypes.includes(type)) {
        warnings.push(
          `@type "${type}" is not in the commonly supported types: ${supportedTypes.join(", ")}`
        );
      }
  
      // Type-specific required field checks
      if (type === "Person" && !schema.name) {
        errors.push("Person schema requires a 'name' field");
      }

• mcp-server/src/index.ts:701-710 (registration)

  Registration of the 'validate_schema' tool, which wraps the 'validateSchema' handler function and takes 'json' as an input parameter.

  server.tool(
    "validate_schema",
    "Validate an existing JSON-LD schema. Checks for required fields, proper @context, valid @type, and common issues.",
    {
      json: z
        .string()
        .describe("JSON-LD string to validate"),
    },
    async ({ json }) => {
      const result = validateSchema(json);