list_templates

Instructions

Implementation Reference

• packages/mcp/src/tools.ts:296-298 (handler)

  The MCP handler function for the 'list_templates' tool. Calls listTemplates() from @engine and wraps result in ok().

  function handleListTemplates(): ToolResult {
    return ok(listTemplates());
  }

• src/lib/engine/templates/index.ts:25-35 (handler)

  Core implementation: iterates TEMPLATE_REGISTRY and returns a lightweight array of TemplateSummary objects (id, name, description, tables, default_counts), omitting the full schema.

  export function listTemplates(): TemplateSummary[] {
    return Object.values(TEMPLATE_REGISTRY).map(
      ({ id, name, description, tables, default_counts }) => ({
        id,
        name,
        description,
        tables,
        default_counts,
      }),
    );
  }

• packages/mcp-server/src/index.ts:291-328 (handler)

  Alternative MCP server registration for 'list_templates' that calls GET /api/v1/templates via an API call rather than using the engine directly.

  server.tool(
    "list_templates",
    `List pre-built schema templates for common application patterns.
  
  Available templates:
  - ecommerce: Customers, products, orders, order items, reviews (5 tables)
  - blog: Authors, posts, comments, tags, post_tags (5 tables)
  - saas: Organizations, members, subscriptions, invoices (4 tables)
  - social: Users, posts, likes, follows, messages (5 tables)
  
  Each template includes realistic field types, proper foreign key relationships,
  weighted enum distributions, and auto-locale detection via country fields.`,
    {},
    async () => {
      const res = await apiCall("GET", "/api/v1/templates");
  
      if (!res.ok) {
        return {
          content: [
            {
              type: "text" as const,
              text: `API error (${res.status}): ${JSON.stringify(res.data, null, 2)}`,
            },
          ],
          isError: true,
        };
      }
  
      return {
        content: [
          {
            type: "text" as const,
            text: JSON.stringify(res.data, null, 2),
          },
        ],
      };
    }
  );

• src/lib/engine/templates/types.ts:12-17 (schema)

  The TemplateSummary interface defining the shape of objects returned by listTemplates() — id, name, description, tables, default_counts.

  export interface TemplateSummary {
    id: string;
    name: string;
    description: string;
    tables: string[];
    default_counts: Record<string, number>;

• packages/mcp/src/tools.ts:143-186 (registration)

  Tool definition registration in the MCP tool definitions array — declares name 'list_templates', description, and empty inputSchema.

    {
      name: "list_templates",
      description:
        "List pre-built schema templates for common database patterns: e-commerce, blog, SaaS, and social network.",
      inputSchema: {
        type: "object",
        properties: {},
      },
    },
    {
      name: "generate_from_template",
      description:
        "Generate test data using a pre-built template. Available templates: ecommerce, blog, saas, social. Use 'scale' to multiply record counts.",
      inputSchema: {
        type: "object",
        properties: {
          template: {
            type: "string",
            description:
              "Template ID: ecommerce, blog, saas, or social",
          },
          locale: {
            type: "string",
            description: "Locale for generated data. Default: en",
          },
          scale: {
            type: "number",
            description:
              "Multiplier for all table record counts. E.g. scale=10 generates 10x the default rows.",
          },
          format: {
            type: "string",
            enum: ["json", "csv", "sql"],
            description: "Output format. Default: json",
          },
          seed: {
            type: "number",
            description: "PRNG seed for reproducible output.",
          },
        },
        required: ["template"],
      },
    },
  ];