@turbot/guardrails-mcp/dist/tools/guardrails_process_template.js

MCP server for interacting with Turbot Guardrails.

import nunjucks from "nunjucks";
import { parse as parseYaml } from "yaml";
import { filters } from "../utils/nunjucksFilters.js";
import { logger } from '../services/pinoLogger.js';
import { formatToolResponse, errorResponse } from '../utils/responseFormatter.mjs';
// Configure nunjucks with custom filters
const env = nunjucks.configure({ autoescape: false, trimBlocks: true, lstripBlocks: true });
// Add all custom filters
Object.entries(filters).forEach(([name, filter]) => {
    env.addFilter(name, filter);
});
export const tool = {
    name: "guardrails_process_template",
    description: "Process input data through a Nunjucks template. The input data is made available as $ in the template. The template must return valid YAML.",
    inputSchema: {
        type: "object",
        properties: {
            template: {
                type: "string",
                description: "The Nunjucks template to process"
            },
            input: {
                type: "object",
                description: "The input data to make available as $ in the template"
            }
        },
        required: ["template", "input"],
        additionalProperties: false
    },
    handler: async ({ template, input }) => {
        try {
            // Process the template with input data
            const result = env.renderString(template, { $: input });
            // Validate that the output is valid YAML
            try {
                parseYaml(result);
            }
            catch (error) {
                const yamlError = error;
                logger.error("Invalid YAML output:", yamlError);
                return errorResponse(`Template output is not valid YAML: ${yamlError.message}`);
            }
            logger.debug("Template processed successfully:", result);
            return formatToolResponse(result);
        }
        catch (error) {
            logger.error("Error processing template:", error);
            const errorMessage = error instanceof Error ? error.message : String(error);
            return errorResponse(errorMessage);
        }
    }
};