paper-preprocess

paper-preprocess is a skill for Claude Code from FrontisAI/NatureBench. It costs 33 tokens per session (714 once invoked), scanned A, original, MIT.

A document-processing tool for CNS research papers, using HTML and PDF files to extract text, figures, tables, and links into structured data. CNS refers to the journals Cell, Nature, and Science.

In plain words
What is it for?
Use it to prepare matching HTML and PDF files for downstream paper filtering, preserving headings and formulas while collecting figures, tables, and links.
Why use it?
It avoids manually copying paper text, finding figures, and collecting links before the papers can be reviewed or filtered.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: agent in frontmatter; installed under .agents/ (shared by several agents).

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is python3 preprocess.py ./s42256-019-0037-0/ ./s42256-019-0037-0/preprocessed.

Good fit Use it to prepare matching HTML and PDF files for downstream paper filtering, preserving headings and formulas while collecting figures, tables, and links.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/FrontisAI/NatureBench
agentmods
npx agentmods add skills/frontisai/naturebench/paper-preprocess

Made for: Claude Code.

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 paper-preprocess

README.md
[![agentmods](https://agentmods.dev/badge/skills/frontisai/naturebench/paper-preprocess/github.svg)](https://agentmods.dev/skills/frontisai/naturebench/paper-preprocess)
Your own site
<a href="https://agentmods.dev/skills/frontisai/naturebench/paper-preprocess"><img src="https://agentmods.dev/badge/skills/frontisai/naturebench/paper-preprocess/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for paper-preprocess

Your own site · 80×15
<a href="https://agentmods.dev/skills/frontisai/naturebench/paper-preprocess"><img src="https://agentmods.dev/badge/skills/frontisai/naturebench/paper-preprocess.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 714 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 5.1 $0.00033 $0.00714
Opus 5.5 $0.00013 $0.00286
Sonnet 5.5 $0.00007 $0.00143
Haiku 4.5 $0.00003 $0.00071

Measured 2mo ago against content hash a9251698045a, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

paper-preprocess 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 2mo ago.

The scan reads SKILL.md. This mod also ships 4 executable files (scripts/extract_figures.py, scripts/extract_links.py, scripts/extract_text.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.

naturegym/.agents/skills/paper-preprocess/SKILL.md · 96 lines

How it starts

The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Paper Preprocess Skill

Preprocess CNS papers using HTML (text/links) and PDF (figures) to extract structured data.

Input Requirements

Before invoking this skill, provide:

  1. Input Directory: A directory containing both *.pdf and *.html files for the same paper (Nature/Springer structured HTML). The folder name is used as paper_id.
  2. Output Directory: The base directory to store preprocessing results

Workflow

Step 1: Extract Text (from HTML)

Use scripts/extract_text.py to extract full text from the HTML:

  • Preserve document structure (headings, paragraphs, bold/italic)
  • Preserve LaTeX formulas
  • Remove citation reference numbers
  • Skip non-content sections (References, Recommendations, Author information, etc.)
  • Output in Markdown format

Step 2: Extract Figures (from PDF)

Use scripts/extract_figures.py to extract figures from the PDF:

  • Detect figure/table captions via structured text blocks
  • Render full pages containing detected figures/tables
  • Fall back to embedded image extraction if no captions found, then to full-page rendering if still empty

Step 3: Extract Links (from HTML)

Use scripts/extract_links.py to extract links from the HTML:

  • Extract hyperlinks from article body sections
  • Classify into data_availability / code_availability / supplementary_information / other by section
  • Identify common link types (GitHub, Zenodo, CodeOcean, etc.)
  • Filter out internal anchors, citation references, and non-content sections

Usage

cd skills/paper-preprocess/scripts

python3 preprocess.py <input_dir> <output_dir>

# Example:
python3 preprocess.py ./s42256-019-0037-0/ ./s42256-019-0037-0/preprocessed

Output Structure

{output_dir}/
  text.md                 # Full paper text (Markdown format)
  figures/                # Figures directory
    Fig_1_page2.png
    Fig_2_page3.png
    ...
  tables/                 # Tables directory
    Table_1_page3.png
    ...
  links.json              # Extracted links with section classification

Read the full file on GitHub · 96 lines

Files

What ships with it

4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 2mo ago First seen · 96 lines · 33 tokens per session scan A a9251698045a

Subscribe to this mod's changes

paper-preprocess is a skill published in the GitHub repository FrontisAI/NatureBench (137 stars, last pushed 17d ago), licensed MIT. It adds 33 tokens to every session and 714 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-30.

Related

paper-preprocess compared with skills from other repositories

paper-preprocess next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
paper-preprocessFrontisAI/NatureBenchSkill13717d agoMITA33Claude Code
pydicomK-Dense-AI/scientific-agent-skillsSkill56k4d agoMITA52Claude Code, Codex
nature-paper2wordYuan1z0825/nature-skillsSkill52k2d agoApache-2.0A233Codex
pptx-postersK-Dense-AI/scientific-agent-skillsSkill56k4d agoMITA59Claude Code
nature-paper-transYuan1z0825/nature-skillsSkill52k2d agoApache-2.0A68Codex
extracting-lab-tablesmaziyarpanahi/openmedSkill5.8kyesterdayApache-2.0A210Claude Code
figuressynthetic-sciences/openscienceSkill4.3k2d agoApache-2.0A99Claude Code