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scraping-html-to-markdown

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Use when the user wants a single page rendered as clean Markdown plus structured metadata. Covers `crawlberg scrape URL`, JSON vs Markdown output, what metadata is returned, and how to handle JS-heavy pages.

QUICK START

How to use this skill

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  1. Open your project in Codex.
  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
Prompt to paste
I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/hashgraph-online/awesome-codex-plugins/blob/HEAD/plugins/kreuzberg-dev/plugins/plugins/crawlberg/skills/scraping-html-to-markdown/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/scraping-html-to-markdown/. Do not write files or run scripts until I approve.

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

Scraping HTML to Markdown

crawlberg scrape <url> is the right tool when the user has a single page in mind. It returns Markdown plus a full structured payload (metadata, links, images, JSON-LD, HTTP response info).

Quick recipe

crawlberg scrape https://example.com/article --format markdown

JSON form (default) when downstream needs metadata:

crawlberg scrape https://example.com/article --format json

Flag surface

FlagDefaultPurpose
--formatjsonjson or markdown.
--timeout30000Per-request timeout in ms.
--proxy—HTTP, HTTPS, or SOCKS5 proxy URL.
--user-agent—Override request UA.
--respect-robots-txtoffHonour robots.txt.
--browser-modeautoauto, always, never — see headless-fallback skill.
--browser-endpoint—External CDP ws:// URL.
--config—Inline JSON or @file.json for full CrawlConfig.

Output shape

Markdown mode

Prints the rendered Markdown only. Use when piping to a file the user will read, or when the result becomes LLM context downstream.

JSON mode

Top-level PageResult with:

  • url, final_url (after redirects), status_code.
  • markdown: { content, fit_content, warnings } — fit_content is a pruned LLM-optimised variant.
  • metadata: Open Graph, Twitter Card, Dublin Core, article tags, JSON-LD, headings (H1–H6), feeds, favicons, hreflang.
  • links: arrays for Internal, External, Anchor, and Document.
  • images: <img>, <picture>, srcset, og:image.
  • tables: structured table data preserved separately from Markdown.
  • response: HTTP headers, content type, charset, body size.

Read result.markdown.content for the Markdown string when scripting.

Common pitfalls

Empty or stub content

Static fetch returned a JS shell. Symptoms in JSON output:

  • markdown.content is short or only contains nav/footer chrome.
  • markdown.warnings mentions JS-render-required.
  • metadata.headings is empty when the page clearly has headings.

Re-run with --browser-mode always and see the headless-fallback skill.

WAF block

Auto mode detects 8 WAF vendors and retries through headless Chrome automatically. If you forced --browser-mode never, the WAF response will fall through. Check response.status_code — 403/406/503 with WAF headers (server: cloudflare, x-amz-cf-id, etc.) is the giveaway.

Robots.txt blocking the fetch

If --respect-robots-txt is set and the path is disallowed, the scrape returns an error rather than partial content. Drop the flag only on hosts you own or have authorisation for.

Wrong charset

Most pages declare UTF-8. Pages that lie about their charset can surface as mojibake in markdown.content. crawlberg exposes no encoding-override option (there is no force_encoding/charset field in CrawlConfig, and --config rejects unknown keys), so an incorrectly declared charset is a server-side defect — re-fetch the raw bytes and transcode them downstream if you hit it.

Examples

Scrape an article for downstream LLM context

crawlberg scrape https://blog.example.com/post-123 --format markdown \
  > /tmp/article.md

Scrape with proxy and custom UA

crawlberg scrape https://example.com \
  --proxy http://proxy.internal:3128 \
  --user-agent "crawlberg (research@example.com)" \
  --format json

Extract just the OG metadata

crawlberg scrape https://example.com --format json \
  | jq '.metadata | {title: .og.title, description: .og.description, image: .og.image}'

When to reach for crawl or interact instead

  • The user wants the whole site, not one page → crawling-a-site skill.
  • The user needs to click, type, or scroll before extracting → use crawlberg interact with the action list.
  • The user only wants the list of URLs → crawlberg map.