LLM Export

generateFixPrompt

Generates a structured Markdown prompt that an LLM can use to fix email compatibility issues.

function generateFixPrompt(options: ExportPromptOptions): string

Parameters

interface ExportPromptOptions {
  originalHtml: string;                      // The original email HTML/JSX/MJML
  warnings: CSSWarning[];                    // Warnings from analyzeEmail()
  scores: Record<string, {
    score: number;
    errors: number;
    warnings: number;
    info: number;
  }>;
  scope: "all" | "current";                 // Fix all clients or just one
  selectedClientId?: string;                 // Required when scope is "current"
  format?: "html" | "jsx" | "mjml" | "maizzle"; // Input format (default: "html")
}

Returns

A Markdown string containing:

Context — format, scope, issue counts
Original email code — the full source in a code block
Compatibility scores table — per-client scores
Detected issues — grouped by severity with before/after fixes
Instructions — what the LLM should do

Example

import {
  analyzeEmail,
  generateCompatibilityScore,
  generateFixPrompt,
} from "@emailens/engine";

const warnings = analyzeEmail(html);
const scores = generateCompatibilityScore(warnings);

const prompt = generateFixPrompt({
  originalHtml: html,
  warnings,
  scores,
  scope: "all",
  format: "html",
});

// Send `prompt` to Claude, GPT, or any LLM to get a fixed version

Scoped to a single client

const prompt = generateFixPrompt({
  originalHtml: html,
  warnings,
  scores,
  scope: "current",
  selectedClientId: "outlook-windows-legacy",
  format: "html",
});

This generates a focused prompt with only Outlook Classic (Word engine) issues and fixes.

When format is set to "jsx", "mjml", or "maizzle", the generated prompt includes framework-specific instructions. For example, with format: "jsx" the prompt tells the LLM to use React Email components (Row, Column, Font, etc.) rather than raw HTML tables.

const prompt = generateFixPrompt({
  originalHtml: jsxSource,
  warnings,
  scores,
  scope: "all",
  format: "jsx",
});
// Prompt includes: "Use React Email components..."

Use with the MCP server

The MCP server's preview_email tool returns data in a format that pairs well with generateFixPrompt. After previewing an email in Claude, you can ask Claude to fix the issues and it will have all the context it needs.