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Instructions

Implementation Reference

• src/prompts/prompts.ts:252-291 (registration)

  Registration of the 'render_prompt' MCP tool, including inline handler function that renders the prompt using registry.prompts.render and returns formatted JSON response.

    "render_prompt",
    "Render a prompt template with the given parameters",
    {
      templateId: z.string().describe("The ID of the template to render"),
      parameters: z.record(z.any()).describe("Parameters for the template"),
    },
    async (args) => {
      try {
        const rendered = registry.prompts.render(args.templateId, args.parameters);
  
        return {
          content: [
            {
              type: "text",
              text: JSON.stringify(
                {
                  templateId: rendered.templateId,
                  content: rendered.content,
                  parameters: rendered.parameters,
                },
                null,
                2
              ),
            },
          ],
        };
      } catch (error) {
        return {
          content: [
            {
              type: "text",
              text: `Error rendering prompt: ${error instanceof Error ? error.message : String(error)}`,
            },
          ],
          isError: true,
        };
      }
    }
  );

• src/core/registry.ts:222-228 (handler)

  Helper function renderPrompt in Registry class that implements PromptExecutor interface by calling this.prompts.render and returning the rendered content.

  async renderPrompt(
    promptId: string,
    parameters: Record<string, unknown>
  ): Promise<string> {
    const rendered = this.prompts.render(promptId, parameters);
    return rendered.content;
  }

• src/prompts/prompts.ts:255-257 (schema)

  Zod schema for input parameters of the 'render_prompt' tool: templateId (string) and parameters (record).

    templateId: z.string().describe("The ID of the template to render"),
    parameters: z.record(z.any()).describe("Parameters for the template"),
  },