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Convert Substack posts to Markdown

Turn a public Substack URL into clean, portable Markdown for LLMs, notes, research, and archives. This guide follows the same domain-swap workflow as the X guide, adapted for Substack.

Want to test the form first? Use the Substack converter or start from the all-platform preview.

Why use AnyPost for Substack?

Notes and posts; note replies when comments is on. Instead of pasting a live URL and hoping an AI tool can read it, AnyPost returns the post as a stable Markdown document with attribution.

ApproachWhat you get
Paste the original linkPreview cards, login walls, or incomplete context
anypost.mdClean Markdown with source URL and platform context

01: Cleaner context
Markdown removes navigation, overlays, embeds, and tracking parameters so models see the post content first.

02: Better archives
The output is plain text, easy to diff, store in Obsidian, add to a CMS, or keep in a research folder.

03: Predictable automation
The browser URL swap and the JSON API share the same conversion pipeline, so scripts and manual workflows produce the same style of output.

Step-by-step workflow

01: Copy the Substack URL
Use the public permalink for the post, article, story, video, pin, or thread you want to preserve.

02: Swap the domain to anypost.md
Open the AnyPost URL in your browser. The platform prefix keeps routing explicit.

Before: https://substack.com/@youssefhosni95/note/c-268090018
After:  https://anypost.md/substack/@youssefhosni95/note/c-268090018

03: Add paid options when needed
Substack requires Pro, Scale, or Agency plus an apk_ key because it is a Pro-tier source with higher fetch cost.

04: Copy the Markdown output
Use the result in a prompt, archive, markdown editor, CMS, or API workflow.

What you get

  • Posts and notes without the paywall chrome
  • Headings, lists and prose preserved
  • Note replies with comments=on
  • Any custom Substack subdomain supported
  • Available on Pro and above
# Example Substack post

Clean post text appears here, with line breaks preserved and noisy page chrome removed.

- Source platform: Substack
- Original URL: https://substack.com/@youssefhosni95/note/c-268090018
- Markdown URL: https://anypost.md/substack/@youssefhosni95/note/c-268090018

---
2026-06-01 · Substack · [Original post](https://substack.com/@youssefhosni95/note/c-268090018)

Good for

  • Feeding exact Substack context into ChatGPT, Claude, Gemini, Cursor, or another AI assistant.
  • Saving source posts in Obsidian, Notion, a research database, or a static-site content folder.
  • Quoting public posts with the original URL and platform timestamp kept together.
  • Building lightweight review, monitoring, or archive scripts around a stable Markdown response.

For agents: fetch Markdown, not web pages

Give AnyPost to OpenClaw, Codex, Cursor agents, Claude Code, and RAG workers as their Substack fetch layer. Instead of driving the original site, the agent should rewrite the URL to anypost.md or call /api/convert, then read the clean Markdown response.

That keeps agents out of brittle DOM scraping, rate-limit loops, login walls, and browser automation noise.

Agent setup

  • Install the anypost-md skill, or give your agent the raw SKILL.md.
  • Store an apk_ key from Login for Agents and send it as Authorization: Bearer apk_live_xxx for paid options.
  • Use the domain-swap URL when the agent wants a plain Markdown document; use /api/convert when it needs JSON fields such as markdown, credits, or structured errors.
Original: https://substack.com/@youssefhosni95/note/c-268090018
Agent:    https://anypost.md/substack/@youssefhosni95/note/c-268090018

Paid options and API usage

Substack is Pro+ only. After buying credits, Login with Google to redeem checkout, create an apk_ key, and pass it with the conversion request:

curl -sS -H "Authorization: Bearer apk_live_xxx" \
  "https://anypost.md/substack/@youssefhosni95/note/c-268090018"

When your app needs JSON fields such as markdown, credits, or structured errors, call /api/convert with the original URL:

curl -sS -H "Authorization: Bearer apk_live_xxx" \
  "https://anypost.md/api/convert?url=https%3A%2F%2Fsubstack.com%2F%40youssefhosni95%2Fnote%2Fc-268090018"
Entry pointResponseBest for
/substack/... domain swaptext/plain MarkdownBrowser, curl pipes, agents that want a document
/api/convert?url=...JSON with markdownApps that need metadata and structured errors

See Documentation for query parameters, credit costs, and authentication.

Substack FAQ

Does AnyPost work with custom Substack domains?

Yes. Any Substack post URL, including custom subdomains, converts. Swap the host for anypost.md and add the /substack/ prefix, which is handled for you.

Can I include Substack note replies?

Yes, on Substack Notes (substack.com/@author/note/c-…). Add comments=on to fetch guest-visible replies. Long-form /p/ articles do not include comment threads yet.

Why is Substack a Pro feature?

Substack is a Pro-tier source, alongside Threads and long-form X articles.

Is Substack available on the free tier?

No. Substack requires Pro, Scale, or Agency plus an apk_ key. Starter covers X tweets, Reddit, Bluesky, Mastodon, Hacker News, YouTube, and Medium.

Can agents use AnyPost instead of scraping Substack?

Yes. Give OpenClaw, Codex, Cursor agents, Claude Code, or your RAG worker the anypost-md skill at /i/skill.md and an apk_ key from Login for Agents. The agent should call AnyPost for Substack URLs and read Markdown instead of scraping the original page, which avoids brittle selectors, rate limits, and login walls.

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