html2md

Aggressive HTML-to-markdown converter for AI agents. Mozilla Readability isolates main content, Turndown converts to markdown, then heavy post-processing strips remaining noise.

> Full flag reference and advanced examples: references/usage.md

Setup

cd <skill-dir>/scripts
npm install
npm link        # makes `html2md` globally available

Requires Node.js 22+.

Quick Start

html2md https://example.com                    # fetch + convert
html2md --file page.html                       # local HTML file
cat page.html | html2md --stdin                # pipe from stdin
html2md --max-tokens 2000 https://example.com  # budget-aware truncation
html2md --no-links https://example.com         # strip hrefs, keep text
html2md --json https://example.com             # JSON: {title, url, markdown, tokens}

Key Features

• Readability extraction — kills navbars, sidebars, ads, cookie banners. Falls back to cleaned when Readability returns too little (e.g. HN's table layout).
• Token budgeting — --max-tokens N keeps all headings, fills remaining budget in document order, appends [truncated — N more tokens]. Uses 1 token ≈ 4 chars heuristic.
• Post-processing — strips HTML comments, zero-width chars, social CTAs, breadcrumbs, empty headings, collapses excess blank lines.
• Error handling — bad URLs, timeouts (15s), non-HTML content, missing files all exit code 1 with descriptive stderr.
• Output modes — plain markdown or --json for programmatic use.

When to Use vs web_fetch

Security Considerations

html2md fetches URLs and reads local files — that's its job. If you're passing untrusted input:

• URL fetching: the tool will fetch whatever URL it's given. Don't pass user-controlled URLs without validation if your threat model includes SSRF.
• File reading: --file reads any path the process can access. In agent workflows, the agent controls the path — this is equivalent to the agent using cat.
• No shell execution: the tool itself never spawns shells or runs commands. When calling from scripts, use execFileSync (not execSync) to avoid shell injection.
• No data exfiltration: output goes to stdout only. No network requests beyond the single URL fetch. No telemetry, no analytics, no phone-home.
• Dependencies: jsdom (Mozilla DOM implementation), Readability (Mozilla content extractor), Turndown (HTML→markdown). All widely audited, open source libraries.

Examples

# Read a Paul Graham essay within 2000 tokens
html2md --max-tokens 2000 https://paulgraham.com/greatwork.html

# HN front page as clean text, no link noise
html2md --no-links --no-images https://news.ycombinator.com

# Get token count before committing
html2md --json https://example.com | jq .tokens

# Pipe to file
html2md https://docs.example.com/api > api-docs.md