# Claude's Document Skills: Excel, PowerPoint, Word, and PDF

> How Anthropic's pre-built document skills let Claude produce real .xlsx, .pptx, .docx, and PDF files — on claude.ai, the API, and in Claude Code.

Anthropic ships four pre-built skills — xlsx, pptx, docx, and pdf — that turn 'make me a spreadsheet' into an actual file, built by code execution with real formatting and structure. They're always active on claude.ai, attachable by skill_id on the API, and open source in the anthropics/skills repo. Better inputs (templates, brand rules, examples) get better documents.

The most-used Claude skills are ones most people don't know are skills: ask claude.ai for a spreadsheet, a slide deck, a formatted Word document, or a filled PDF, and what answers isn't the base model winging it — it's one of four Anthropic-built **document skills** (`xlsx`, `pptx`, `docx`, `pdf`) loading and driving code execution to produce a real file. They're also the clearest demonstration of what the [skills format](/guides/skills/what-are-claude-skills) is for.

## What they actually do

Each document skill is a normal SKILL.md-plus-resources package that encodes *format craft*: how a workbook should be structured, what makes a slide layout hold up, how document styles and sections work. When one activates, Claude writes and runs code against the Python document stack in the execution sandbox — `openpyxl` for Excel, `python-pptx` for PowerPoint, `python-docx` for Word, PDF tooling for forms and extraction — following the skill's procedure instead of improvising.

The difference is visible in the output. Without the skill, "make me a budget spreadsheet" gets you a Markdown table. With it, you get an `.xlsx` with separate input and summary sheets, real formulas, and formatting — a file you open in Excel and keep using.

## Where they're available

| Surface | Status |
|---|---|
| claude.ai (web/desktop) | **Always active** — nothing to install; code execution on |
| Claude API | Attach by `skill_id` via the `container` parameter |
| Managed Agents | Add to the agent's `skills` list (`{"type": "anthropic", "skill_id": "xlsx"}`) |
| Claude Code | Available in beta; also installable from the public anthropics/skills repo |

On the API, a request looks like this (both betas required):

```python
response = client.beta.messages.create(
    model="claude-opus-4-8",
    max_tokens=16000,
    betas=["code-execution-2025-08-25", "skills-2025-10-02"],
    container={"skills": [{"type": "anthropic", "skill_id": "pptx", "version": "latest"}]},
    tools=[{"type": "code_execution_20260521", "name": "code_execution"}],
    messages=[{"role": "user", "content": "Create a 5-slide QBR deck from these notes: ..."}],
)
```

The generated file lives in the container; the response carries its file ID, and you download it via the Files API. The full API mechanics — `/v1/skills`, limits, the no-network constraint — are in [Skills on claude.ai and the API](/guides/skills/claude-skills-on-claude-ai-and-api).

## Getting good documents, not just documents

The skills handle format mechanics; content quality is still yours to specify. The patterns that consistently raise output quality:

1. **Provide the skeleton.** A slide-by-slide brief, a column list with example rows, or the section outline. The skill turns structure into format; it can't invent your argument.
2. **Anchor to an existing file.** Upload last quarter's deck or your report template and ask Claude to match it — the skills read existing documents with the same libraries they write with.
3. **State the format rules once.** Brand colors, font, "no more than four bullets per slide", "currency to two decimals" — explicit constraints are followed reliably.
4. **Ask for a verification pass.** "Before finishing, re-open the file and check every formula resolves and no cell shows an error" — the skill runs code, so it can actually check its own artifact.
5. **Iterate on the file, not from scratch.** Follow-ups ("make sheet 2 a pivot by region") edit the existing artifact rather than regenerating.

## Limits worth knowing

The execution container is sandboxed: **no network access**, so a document skill can't pull live data mid-build — provide the data in the conversation or as an uploaded file. On the API, uploads run through the Files API and requests carry at most 8 skills. And very large or intricate documents (hundred-tab workbooks, pixel-perfect design decks) still hit the ceiling of what code-built documents do well — the skills raise the floor dramatically; they don't replace a designer.

## Why they matter beyond documents

The document skills are the reference implementation for the whole format. If you're [writing your own skill](/guides/skills/writing-your-first-skill), read the `xlsx` SKILL.md in anthropics/skills first: one job, a tight procedure, deterministic work pushed into code, and boundaries stated plainly. Our [annotated examples](/guides/skills/claude-skills-examples) walk the same patterns at smaller scale.

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_Source: https://agentscamp.com/guides/skills/claude-document-skills — Guide on AgentsCamp._