converting-email-templates

Converting email templates

Purpose

Automatically convert email templates from other email service providers into Mailtrap-compatible Handlebars syntax. Handles both deterministic pattern conversions (via a Python script) and complex edge cases (via LLM intelligence).

Related skills: using-email-templates (Handlebars syntax, API template send), sending-emails (stream bases and auth), authorizing-api-requests (tokens, env vars, account_id resolution — needed when creating templates or sending via the Templates API after conversion).

Input

• Source provider (required): sendgrid, mailgun, mandrill-handlebars, mandrill-mergetags, postmark, brevo, or ses
• Input: a single template file path, a directory of .html template files, or raw HTML pasted inline
• Output directory (optional): defaults to a /converted/ subdirectory next to the input

If the user does not specify the source provider, ask before proceeding. If the user provides template HTML inline (pasted in chat), save it to a temporary .html file first.

Workflow

Step 1: Detect mode

Fast mode (default): For providers with deterministic conversion patterns. The Python script handles these reliably.

Deep mode: Triggered when:

• Provider is brevo AND the template contains nested loops, multiple filters, or complex conditional nesting
• The script flags patterns that could benefit from LLM judgment
• The user explicitly requests deep mode
• Inline HTML is provided (run LLM conversion directly)

Step 2: Run the converter script

Execute the Python converter script:

python3 {skill_dir}/scripts/converter.py \
  --provider {provider} \
  --input {input_path} \
  --output {output_dir}

Where {skill_dir} is the directory containing this SKILL.md file.

Read the output:

• Exit code 0: clean conversion, no flags. Proceed to Step 4.
• Exit code 1: conversion completed with flags. Proceed to Step 3.
• Exit code 2: error. Report to user and stop.