Claude PDF skill review: verdict, safety and alternatives
Anthropic's Claude PDF skill teaches an agent to read, extract, merge, split, create and fill PDFs with Python libraries. We rate it Conditional, 68/100, at Moderate confidence, because its form-filling scripts carry unfixed defects.
- Verdict
- Conditional
- Score
- 68/100
- Confidence
- Moderate
- Safety grade
- B
- Best for
- Routine PDF reading, table extraction, merging, splitting, watermarking and Latin-script generation in a Python sandbox
- Poor fit
- Unattended filling of government or business forms
- Reviewed version
- anthropics/skills commit 8a1541c (2026-09-28); skills/pdf last changed 2026-02-06; no version
- Review date
- 2026-09-30
- Works in verified
- Claude Code
- Works in claimed
- Claude.ai, Claude API
- Status
- no change to skills/pdf since review (checked 2026-10-21); 9 fix PRs still open
Get the skill: pdf folder on GitHub · SKILL.md at the reviewed commit · skills.sh listing
What is the Claude PDF skill, and where is it on GitHub?
The Claude PDF skill is Anthropic's official skill for reading, extracting, merging, splitting, creating and filling PDFs. It lives in the anthropics/skills GitHub repository under skills/pdf, with SKILL.md, two reference files and eight Python scripts.
The skill is an Agent Skill: a SKILL.md package Claude loads when a request mentions a PDF. Our guide explains how Agent Skills load. The long form-filling procedure sits in forms.md.
| Fact | Value |
|---|---|
| Publisher | Anthropic |
| Repository and path | anthropics/skills, skills/pdf (SKILL.md) |
| Files | 12: SKILL.md, forms.md, reference.md, LICENSE.txt and 8 Python scripts |
| Scripts | fill_fillable_fields, convert_pdf_to_images, extract_form_field_info, extract_form_structure, check_bounding_boxes, create_validation_image, fill_pdf_form_with_annotations, check_fillable_fields |
| Licence | Proprietary terms in LICENSE.txt; the README calls it source-available, not open source |
| Version | None; skills/pdf last changed 2026-02-06 (1ed29a0) |
| Installs | 203.9K on skills.sh, of 3.3M for the whole repository |
It needs Python 3, pypdf, pdfplumber, reportlab, pdf2image, Pillow and Poppler. qpdf, pdftk and Tesseract are optional. The agenticskills.io directory wrongly lists the licence as Apache-2.0. The Agent Skills overview describes the pre-built pdf skill more narrowly: "Generate formatted PDF documents and reports".
Is the Claude PDF skill worth installing?
Yes, the Claude PDF skill is worth installing for everyday PDF work, with care on forms. It scores 68/100, Conditional, at Moderate confidence. Its extraction and creation recipes are current, but its form-filling scripts carry reproduced, unfixed defects.
Its strength is short, copy-paste code on current library APIs. Its form helpers mishandle choice options, rotated pages and same-path output. It fits 2 cases poorly:
- Unattended filling of government or business forms, where a misplaced value goes unnoticed.
- Japanese, Chinese or Korean PDFs that recipients open in Adobe Acrobat.
Read our scoring rules for the weights.
| Parameter | Score |
|---|---|
| Effectiveness | 75 |
| Reliability | 52 |
| Safety | 78 |
| Efficiency | 75 |
| Compatibility | 62 |
| Maintainability | 30 |
| Setup friction | 65 |
| Form-fill correctness | 45 |
| Honest failure reporting | 40 |
| Core recipe currency | 82 |
| Non-Latin and complex-layout output | 40 |
| Cost of adoption | 65 |
| Instruction weight vs value | 78 |
Tessl's run with Sonnet 4.6 is older than the evidence we weighed. The score weighs the worst failure most: a wrong or overwritten form reported as done. Compare it with all skills ranked by verdict.
How many tokens does the Claude PDF skill use?
The Claude PDF skill loads 2,018 tokens of instructions, our measured file size per load. Reference files add about 7,503 more when opened. Filling a 3-page form costs about 15,000 input tokens by our estimate.
| Figure | Tokens | Basis |
|---|---|---|
| SKILL.md per load | 2,018 | Measured file size per load |
| forms.md and reference.md | 7,503 | Measured, loaded only when opened |
| Whole folder | 9,521 | Measured file size |
| Typical task input | 15,000 | Our estimate for a typical task |
| Typical task output | 3,000 | Our estimate for a typical task |
| Typical task input with skill | 18,018 | Our estimate for a typical task |
The typical task is filling a 3-page fillable form, five times a week. Page renders for visual checks add image tokens per page (estimate).
Is the Claude PDF skill safe to install?
Yes, the Claude PDF skill is safe to install with care: it carries safety grade B. Its eight Python scripts work on local files only. One script silently overwrites the input form when both paths match.
Our review of the folder at commit 8a1541c found these safety facts:
- No network indicators, environment variables, hooks or MCP configs.
- Local file reads and writes only, through pypdf, pdfplumber, pdf2image and Pillow.
- Silent input overwrite in fill_fillable_fields.py when output and input paths match (#1617).
- Runtime monkeypatch of a pypdf internal to normalise choice options.
- No prompt-injection guidance for text extracted from untrusted PDFs.
- No telemetry: PR #1076 for this folder closed unmerged.
- skills.sh audits: Gen Agent Trust Hub pass, Socket pass, Snyk warn without published detail.
One directory shows a "Security Score 70/100" and cites secrets in the docs. We found no secrets in the files, which is why our grade differs. See how to vet a skill before use for the full grading method.
What does the community report about the Claude PDF skill?
The community reports a working core and broken form helpers for the Claude PDF skill. One user filled all 196 fields of IRS Form 8802. Reproduced issues document corrupted dropdowns, misplaced annotations and blank Japanese text.
| Source | Date | Finding | Sentiment |
|---|---|---|---|
| Issue #1024 | 2026-04 | Render-inspect-fill fit IRS Form 8802; 196 fields extracted after a pypdf upgrade | Positive |
| Issue #1025 | 2026-04 | convert_pdf_to_images.py crashes when the output folder is missing | Negative |
| Issue #1078 | 2026-05 | pdftotext -layout columns drift across pages; no guidance in the skill | Negative |
| Issue #1369 | 2026-06 | Japanese PDFs show blank text in Adobe Acrobat | Negative |
| Issue #1469 | 2026-07 | Bare-string choice options are corrupted or crash extraction | Negative |
| PR #1481 | 2026-07 | Uppercase REFERENCE.md and FORMS.md links; files are lowercase | Negative |
| Issue #1617 | 2026-08 | Same output path silently overwrites the input form | Negative |
| PR #1568 | 2026-08 | CJK Acrobat fix mergeable, awaiting maintainer review | Negative |
| Issue #1770 | 2026-09 | Forms step 1 cannot run; bounding-box checker exits 0 on failure | Negative |
| PR #1905 | 2026-09 | Annotations misplaced on rotated or cropped pages; tests fail on main | Negative |
| PR #1903 | 2026-09 | Long PDFs render every page into memory before saving | Negative |
| PR #1888 | 2026-09 | One malformed None field node crashes form extraction | Negative |
| Tessl quality review | 2026-09 | Description 100%, content 72%, impact 95% | Neutral |
What are the Claude PDF skill's known failures?
The Claude PDF skill has six known failures at commit 8a1541c. Dropdown options corrupt, rotated pages misplace annotations, and a validator exits 0 on failure. Inputs get overwritten, Japanese text renders blank, and missing folders crash.
A filled form with wrong values, reported as done, costs the most. The six failures:
- Corrupted or crashing string /Opt choice options (#1469).
- Misplaced annotations on rotated or cropped pages (PR #1905).
- Exit code 0 from check_bounding_boxes.py on failure (#1770).
- Silent input overwrite when both paths match (#1617).
- Blank CJK text in Acrobat (#1369).
- Crash on a missing output folder (#1025).
Three smaller defects add to them:
- Broken uppercase links on case-sensitive filesystems (PR #1481).
- Memory load from rendering every page of a long PDF (PR #1903).
- Column drift on multi-page positional tables (#1078).
Contributors opened about two dozen fix PRs, and none has merged. Nine named PRs stayed open on 2026-10-21.
Which agents and plans include the Claude PDF skill?
The Claude PDF skill is verified in Claude Code. Anthropic ships it in Claude.ai and the Claude API as the pre-built pdf skill. Anthropic's sources disagree on plans: the Help Center says all plans, the README says paid plans.
| Surface | Status | Source |
|---|---|---|
| Claude Code | Verified | Repository install |
| Claude.ai | Claimed by Anthropic | Help Center, platform docs |
| Claude API | Claimed by Anthropic | Platform docs, skill_id pdf |
| Claude Code pre-built | Not available | Platform docs; the repository copy installs instead |
Two Anthropic sources conflict on plans. The Help Center lists skills on Free, Pro, Max, Team and Enterprise. The anthropics/skills README says the example skills are "already available to paid plans in Claude.ai". Code execution must be on in both cases. Browse skills ranked for Claude Code for others verified there.
How do you install the Claude PDF skill?
Install the Claude PDF skill in Claude Code from the anthropics/skills marketplace as part of the document-skills plugin. In Claude.ai, turn on code execution and the skill is ready. In the API, reference skill_id pdf.
In Claude Code
- Add the marketplace:
/plugin marketplace add anthropics/skills. - Install the bundle:
/plugin install document-skills@anthropic-agent-skills. - Install the Python packages with pip, plus Poppler from your system package manager.
Our Claude Code skill setup walkthrough covers folders and scopes.
In Claude.ai and the Claude API
- Open Settings > Capabilities and turn on Code execution and file creation (Free, Pro, Max).
- Use Organization settings > Plugins & skills on Team and Enterprise.
- Check the skill under Customize > Skills, per the Help Center.
- Pass
skill_id: "pdf"incontainerwith the code execution tool for the API.
The API container has no network access and no runtime package install. Our guide shows how to turn on skills in the Claude app.
How do you use the Claude PDF skill to read, edit and fill PDFs?
Use the Claude PDF skill by handing Claude a PDF. Ask for text, tables, a merge or a filled form, and the skill triggers on its own. Check every filled form by eye, because validators can report false success.
| Task | Use | Evidence |
|---|---|---|
| Extract text and tables | Primary | SKILL.md; #1078 table gap |
| Fill fillable forms | Primary | #1024, #1469, #1770 |
| Fill flat forms with annotations | Secondary | PR #1905, #1770 |
| Generate reports with reportlab | Secondary | #1369 |
| Merge, split, rotate, watermark, encrypt | Claimed only | Publisher SKILL.md |
| OCR scanned PDFs | Claimed only | Publisher SKILL.md |
Test it yourself:
- Run the forms workflow on one fillable form with a dropdown.
- Run it on one rotated flat form.
- Open both outputs in Acrobat.
- Check every value.
Can the Claude PDF skill create or design PDFs?
Yes, the Claude PDF skill creates PDFs with reportlab Platypus, covering text, tables and simple layouts. It gives no typography or design-system guidance. Japanese, Chinese and Korean text can render blank in Adobe Acrobat (#1369). The doc fix, PR #1568, is still unmerged.
What are the alternatives to the Claude PDF skill?
The closest alternative to the Claude PDF skill is OpenAI's PDF skill for Codex, Conditional at 62. The claude-office-skills collection is unevaluated. Anthropic's PPTX and XLSX skills cover the other office formats.
| Skill | Verdict and score | Better choice when |
|---|---|---|
| OpenAI PDF skill | Conditional, 62, Low confidence | You work in Codex, Copilot or OpenCode |
| claude-office-skills/skills | Not evaluated | You want a community office bundle |
| Anthropic PPTX skill | Recommended with caveats, 71 | You build slide decks |
| Anthropic XLSX skill | Recommended with caveats, 70 | You build spreadsheets |
| Anthropic DOCX skill | Conditional, 66 | You need Word files or tracked changes |
Read Anthropic's PowerPoint skill verdict for decks and Anthropic's Excel skill verdict for spreadsheets.
Common questions
How do you create a PDF skill for Claude?
Write a SKILL.md with a name, a description and your PDF steps. Our guide shows how to build your own skill.
Does Claude have a skill-creator skill?
Yes, Anthropic publishes one for drafting and testing new skills. Read the skill-creator review first; it scores Conditional at 57.
Can Claude modify a PDF?
Yes. Through the skill's scripts, Claude merges, splits, rotates, watermarks and fills forms.
Can I download the PDF skill?
Yes, from anthropics/skills on GitHub. You can install the document-skills plugin instead.
Where are the Claude skills docs?
Anthropic keeps them in the platform docs Agent Skills overview and the Help Center article "Use skills in Claude".
Is the Claude PDF skill free?
Yes, it is free to use in Claude, under a source-available licence. The Help Center says all plans; the README says paid plans.
Can the Claude PDF skill convert PDF to Markdown?
No, it has no dedicated converter. It extracts text and tables an agent writes as Markdown, with column drift on multi-page tables (#1078).