By the end of this lesson, you will have installed Anthropic's document-processing skills and confirmed Claude Code can build a real, openable .docx file. Out of the box, Claude Code can read a Word file as compressed text and struggles to write a properly formatted one. These skills fix both.
Lesson 4.3 ends with Claude Code assembling a running Word document — an agreement summary, a follow-up email, a response, and your notes, added to the same file every day without breaking its formatting. That only works if Claude Code has the right skill installed first. This lesson is that one-time setup step.
1What a Skill Adds That Plain Claude Code Doesn't Have
A .docx, .pptx, or .xlsx file is not plain text — it is a small archive of formatting instructions. Without a skill telling it how, Claude Code can still open one, but it reads it as compressed, hard-to-follow content, and writing a new one from scratch produces a file that often will not open correctly in Word or PowerPoint.
| Without the Skill | With the Skill Installed |
|---|---|
| Claude Code reads a .docx as raw, hard-to-parse content | Claude Code reads the actual formatted text, tables, and headings |
| A new Word file Claude Code writes often has broken formatting or won't open cleanly | A new Word file opens correctly, with real headings, tables, and page setup |
| PDFs are readable but nothing can be extracted cleanly | Text and simple tables extract cleanly from a PDF |
| PowerPoint decks are barely usable as input or output | Claude Code can read slide content and build a properly formatted deck |
Anthropic packages docx, pdf, pptx, and xlsx together as a single plugin called document-skills. You install it once and get all four.
If you never ask Claude Code to touch a Word, PDF, or PowerPoint file, you don't need this. Lesson 4.3 needs it for its Word-document step, so install it now if you plan to do that lesson.
2Add Anthropic's Skill Marketplace
Claude Code does not ship with every possible skill pre-installed. Skills come from a marketplace — a catalog of installable plugins — and you point Claude Code at one before you can install anything from it.
- Open Claude Code in a terminal (any project folder is fine for this step).
- Type the command below and press Enter.
- Wait for Claude Code to confirm the marketplace was added.
/plugin marketplace add anthropics/skills
What you should see:
Marketplace "anthropic-agent-skills" added. Run /plugin install <name>@anthropic-agent-skills to install a plugin from it.
You only need to add a given marketplace once per computer. Every future Claude Code session already knows about it.
A marketplace is a catalog of instructions Claude Code will follow. anthropics/skills is Anthropic's own official repository. Do not add a marketplace from an unfamiliar source without checking with your IT or security team first.
3Install the Document Skills
With the marketplace added, installing the actual skills is one more command.
- In the same Claude Code session, type the install command below.
- Press Enter and wait for confirmation.
- Restart Claude Code (close and reopen your terminal, or start a new session) so the new skills load.
/plugin install document-skills@anthropic-agent-skills
What you should see:
Installed "document-skills" (docx, pdf, pptx, xlsx). Restart Claude Code for the new skills to take effect.
Type /plugin at any time to see a list of every marketplace and plugin currently installed on your computer.
4Verify It Worked
The fastest proof a skill is active is asking Claude Code to use it.
- Open a project folder in Claude Code (any folder — this is just a test).
- Type the prompt below.
- Open the resulting file in Word (or a viewer that supports .docx) and confirm it looks like a real document, not broken formatting.
Create a one-page Word document called skill-test.docx with a title, "Skill Test," and three bullet points describing what you can now do with Word files that you couldn't do before this skill was installed.
What you should see: a real skill-test.docx file appears in your project folder's Explorer sidebar. Opening it shows a formatted title and three bullet points — not a wall of XML or broken text.
Confirm you restarted Claude Code after Step 3. Skills load at session start, not mid-session.
Verification
If the test file won't open or looks broken, confirm the install completed in Step 3 and that you restarted the session. If it still fails, run /doctor and check the output for a plugin-related error.
Related Resources
- claude.ai — The Claude AI platform
- code.claude.com/docs — Official documentation
- support.claude.com — Help center and troubleshooting
Lesson complete
Claude Code can now read and write real Word, PDF, and PowerPoint files — everything Lesson 4.3's Word-document step needs. Delete skill-test.docx once you've confirmed it opens correctly; it was only there to prove the install worked.