How do I install the Ksef Fa3 Claude Code skill?

Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/ksef-fa3/SKILL.md and restart Claude Code. Both flows are detailed at https://claudskills.com/install/.

Is this skill free to install?

Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.

ClaudSkills / General / business-ops

Ksef Fa3

Category: General · Sub-category: business-ops · Last updated: 2026-05-08

Generate and validate KSeF FA(3) e-invoices — Poland's mandatory structured invoice format (effective from 2026-02-01 for large companies, 2026-04-01 for all). Use this skill whenever the user asks about: issuing invoices to KSeF, FA(3) XML structure, mapping invoice data to the FA(3) schema, e-invoice validation, KSeF validator errors, P_12/P_13/GTU/Adnotacje fields, invoices for foreign buyers (EU, non-EU), foreign currency invoices, reverse charge, WDT, export, VAT exemption, advance invoices, corrective invoices, or any FA(3) logical structure question.

What this skill does

Ksef Fa3 is a community-contributed Claude Code skill in the business-ops sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/ksef-fa3/ and loads when your prompt matches the skill's trigger.

Who uses this skill

The Ksef Fa3 skill is built for Claude Code users and developers across all disciplines looking for general-purpose AI assistance. It is part of the open ClaudSkills registry, a community-curated catalog of 56,000+ capabilities you can install for Claude Code — the Claude CLI agent.

How to install

Free

Manual install (2 steps)

mkdir -p ~/.claude/skills/ksef-fa3
curl -L https://claudskills.com/skills/ksef-fa3/SKILL.md \
  -o ~/.claude/skills/ksef-fa3/SKILL.md

Or just download SKILL.md directly and drop it into ~/.claude/skills/ksef-fa3/. Claude Code auto-discovers it on next session.

Skills live at ~/.claude/skills/ksef-fa3/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\ksef-fa3\SKILL.md on Windows. See the full install guide for step-by-step instructions.

Pro

One-click install via the desktop app

The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.

Pro

For the full experience including quality scoring and one-click install features for each skill — upgrade to Pro.

See pricing → Download desktop app

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Part of ClaudSkills — the open registry for Claude Code skills. · What's New · Install guide · About · llms.txt

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