pdf-merge

name	pdf-merge
description	Merge, split, or reorder PDF files. Use when the user mentions combining PDFs, extracting pages, or any "glue these PDFs together" request. Activates automatically in directories containing .pdf files.
license	KohakuTerrarium License 1.0
paths	["*.pdf","**/*.pdf"]

pdf-merge

Use this skill for any operation on PDF files: merging, splitting, reordering pages, or extracting a subset.

Decision tree

Task	Tool
Combine 2+ PDFs into one	qpdf or pdftk
Extract page ranges	qpdf --pages
Reorder pages	qpdf --pages
Convert PDF to images / text	Not this skill —
	use a dedicated
	tool (pdftotext,
	pdfimages).

Merging (preferred: qpdf)

qpdf --empty --pages in1.pdf in2.pdf in3.pdf -- merged.pdf

Fallback when qpdf is not installed:

pdftk in1.pdf in2.pdf in3.pdf cat output merged.pdf

Verification (required)

Always count pages in the output and sanity-check against the sum of the inputs:

qpdf --show-npages merged.pdf

Report the page count back to the user. If the numbers don't add up, flag it — a malformed input PDF silently drops pages in some concatenation tools.

Safety

• Never overwrite the original inputs. Write to a new filename.
• If the output file already exists, ask before overwriting.
• Do not --linearize unless the user asks for it (changes file size noticeably).