feat: markitdown implementation

[SAHIL-Sharma21]

✨ What’s new

This PR adds Markdown (.md) output support using Microsoft MarkItDown as a new CLI-backed converter.

Supported conversions:

PDF → Markdown

DOCX → Markdown

PPTX → Markdown

HTML → Markdown

🤔 Why MarkItDown

MarkItDown provides:

High-quality, semantic Markdown output

Better structure preservation (headings, lists, links)

Automatic input type detection

A CLI interface that aligns well with ConvertX’s architecture

This makes it a strong alternative to existing document converters for Markdown output.

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Summary by cubic

Adds Markdown output via Microsoft MarkItDown, integrated as a new CLI-backed converter. Converts PDF, DOCX, PPTX, HTML, and Excel files to .md with better structure preservation.

• New Features

  • Added MarkItDown converter and registered it in the main converters map.
  • Inputs: pdf, docx, pptx, html, excel; Output: md.
  • Uses the MarkItDown CLI for structured, semantic Markdown.

• Migration

  • Docker image now installs MarkItDown via pipx; markitdown is available in PATH.
  • For local runs, install the MarkItDown CLI and ensure markitdown is in PATH. No config changes required.

^{Written for commit f2dcc7f. Summary will update automatically on new commits.}

[cubic-dev-ai]

1 issue found across 2 files

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="src/converters/main.ts">

<violation number="1" location="src/converters/main.ts:131">
P2: Inconsistent naming convention: all other converter keys use lowercase (e.g., `pandoc`, `libreoffice`, `ffmpeg`), but `MarkitDown` uses PascalCase. This could cause lookup failures if callers pass `markitdown` (following the established pattern). Consider renaming to `markitdown` for consistency.</violation>
</file>

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[C4illin]

Great work! Feel free to merge when you want :)