markmaton

markmaton is a lightweight HTML-to-Markdown parser core built for agent workflows.

It solves the last-mile parsing problem in a web pipeline: you already have page HTML, but it is still too noisy and awkward for downstream agent use. Feed markmaton HTML from a fetcher or browser layer and get back cleaner Markdown, metadata, links, images, and quality signals.

[!NOTE] markmaton is a general parser, not a crawler. Feed it HTML from Playwright, fetch, Firecrawl, or another upstream page-visit tool.

Why it exists

• Raw page HTML is usually not directly useful for downstream agent workflows.
• Modern pages often mix the real content with navigation, overlays, cards, and app shell chrome.
• markmaton keeps that cleanup and conversion step deterministic and separate from crawling.
• The project stays narrow by design: no crawling, browser control, network, or LLM features.
• The user-facing entrypoint is a Python CLI and API wrapped around a fast Go engine.

Install

pip

pip install markmaton

uv tool

uv tool install markmaton

[!TIP] The installed package works through plain pip. Local development uses uv with Python 3.12.

Quickstart

CLI

markmaton convert \
  --html-file page.html \
  --url https://example.com/article \
  --output-format markdown

To get the full structured response:

markmaton convert \
  --html-file page.html \
  --url https://example.com/article \
  --output-format json

Python API

from markmaton import ConvertOptions, ConvertRequest, convert_html

html = "<article><h1>Hello</h1><p>World</p></article>"

response = convert_html(
    ConvertRequest(
        html=html,
        url="https://example.com/article",
        options=ConvertOptions(only_main_content=True),
    )
)

print(response.markdown)
print(response.metadata.title)

[!TIP] Pass url whenever you can. markmaton uses it as parsing context for canonical metadata and absolute link resolution.

Output

JSON mode returns markdown, html_clean, metadata, links, images, and quality. See response shape for details.

Project shape

• Go engine: cmd/markmaton-engine
• Python wrapper and CLI: markmaton/
• Parser fixtures and golden files: testdata/
• Architecture, benchmark, and release docs: docs/

Documentation

• Documentation index
• Usage guide
• Packaging layout
• PyPI release path
• Benchmark and regression workflow
• Regression corpus
• AI agent skill — for using markmaton inside an agent workflow

Development

Set up the local development environment:

uv sync --group dev

Run the core test suites:

uv run python -m unittest discover -s tests -p 'test_*.py'
go test ./...

For a manual end-to-end smoke:

• Local smoke flow

The repo is pinned to:

• Python 3.12 via .python-version
• a committed uv.lock

[!IMPORTANT] Automated tests are unit-test-first. Live page visits and benchmarks are manual.

Release notes

• Changelog
• GitHub Releases