crawl4ai

crawl4ai is a skill for Claude Code, Codex from keysersoose/claude-code-setup. It costs 74 tokens per session (976 once invoked), scanned A, original, MIT.

A web-crawling tool that turns ordinary and JavaScript-rendered pages into Markdown or structured data, with optional screenshots and PDFs.

In plain words
What is it for?
Use it to collect page content, extract selected fields such as CSS or JSON, crawl many pages, and check whether the captured information is complete.
Why use it?
A simple page fetch can miss content that appears only after scripts run or that is difficult to inspect in raw HTML.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/keysersoose/claude-code-setup/crawl4ai
Any agent
npx skills add keysersoose/claude-code-setup --skill crawl4ai
Clone the repo
git clone --depth 1 https://github.com/keysersoose/claude-code-setup

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for crawl4ai

README.md
[![agentmods](https://agentmods.dev/badge/skills/keysersoose/claude-code-setup/crawl4ai.svg)](https://agentmods.dev/skills/keysersoose/claude-code-setup/crawl4ai)
Your own site
<a href="https://agentmods.dev/skills/keysersoose/claude-code-setup/crawl4ai"><img src="https://agentmods.dev/badge/skills/keysersoose/claude-code-setup/crawl4ai.svg" alt="Measured on agentmods" height="20"></a>
Per session 74 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 976 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00074 $0.00976
Opus 5 $0.00037 $0.00488
Sonnet 5 $0.00015 $0.00195
Haiku 4.5 $0.00007 $0.00098

Measured 5d ago against content hash 12d6fc731f5f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

crawl4ai scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

The scan reads SKILL.md. This mod also ships 4 executable files (scripts/batch_crawler.py, scripts/crawl_url.py, scripts/extraction_pipeline.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/crawl4ai/SKILL.md · 105 lines

How it starts

The opening of the file, as written. The whole thing — 105 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Crawl4AI

Overview

Use this skill to crawl web pages into inspectable markdown or structured JSON. In this repository, crawl4ai is a required peer for deep-research: search discovers sources, Crawl4AI captures raw/source content, and the research skill synthesizes evidence.

The skill is harness-neutral. Use the local CLI, Python SDK, Docker API, MCP bridge, or an equivalent harness-provided Crawl4AI tool.

Required Setup

Install Crawl4AI in the Python runtime used by the current agent:

python -m pip install -U crawl4ai
crawl4ai-setup
crawl4ai-doctor

Official project: https://github.com/unclecode/crawl4ai

If the crwl command is available:

crwl crawl https://example.com -o markdown --bypass-cache

If the current harness uses a dedicated virtual environment, run the same commands with that environment's Python and crwl executable. Do not hardcode another machine's venv path in reusable skills.

If browser setup fails:

python -m playwright install chromium

On Linux servers that need browser system dependencies:

python -m playwright install --with-deps chromium

Core Workflow

  1. Start from URLs selected by advanced-web-search, browser inspection, or user input.
  2. Choose the lightest adequate capture mode:
    • simple markdown for normal pages
    • scan_full_page, wait_for, or longer timeout for dynamic pages
    • CSS/JSON extraction for repeated structured pages
    • screenshot/PDF only when visual evidence matters
  3. Capture raw markdown/JSON into a durable path such as research/raw/YYYY-MM-DD/<topic>/.
  4. Inspect extraction quality before using the content:
    • non-trivial length
    • expected title/headings/entities
    • no login wall, CAPTCHA, cookie-only shell, or empty JS shell
    • relevant section present, not just boilerplate
  5. Mark each source as fetched, partial, blocked, empty, or needs_review.
  6. Pass raw paths and quality notes back to deep-research for source cards and evidence matrices.

Read the full file on GitHub · 105 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 105 lines · 74 tokens per session scan A 12d6fc731f5f

Subscribe to this mod's changes

crawl4ai is a skill published in the GitHub repository keysersoose/claude-code-setup (2 stars, last pushed 2mo ago), licensed MIT. It adds 74 tokens to every session and 976 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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