Vellum Prep

Vellum Prep

Convert markdown manuscripts to Vellum-ready Word documents.

When to Use

Use this skill when you have a markdown manuscript (from OCR, writing, or conversion) that needs to be formatted for import into Vellum book formatting software.

What It Does

Programmatic cleanup (no AI tokens):

• Removes OCR metadata headers
• Converts --- to *** (Vellum ornamental breaks)
• Removes duplicate running headers (e.g., repeated book title)
• Removes [Image: ...] placeholder descriptions
• Strips publisher front matter (catalogs, copyright boilerplate)
• Normalizes chapter headings to # Chapter X: Title format
• Cleans common artifacts (page numbers, ellipses, broken hyphenation)
• Converts to .docx via pandoc

Usage

# From the manuscript directory:
python3 /path/to/vellum_prep.py manuscript.md

# Output: manuscript_vellum.md + manuscript.docx (if pandoc available)

Or invoke via Claude:

/vellum-prep manuscript.md

Vellum Formatting Rules

| Markdown | Word Style | Vellum Element | |----------|-----------|----------------| | # Chapter 1: Title | Heading 1 | Chapter | | # Dedication | Heading 1 | Dedication | | # Prologue | Heading 1 | Prologue | | ## Section | Heading 2 | Level 1 Subhead | | *** | Centered asterisks | Ornamental Break | | Single blank line | Blank paragraph | Scene Break |

Configuration

Edit the script to customize:

• header_patterns: List of regex patterns for headers to remove
• remove_images: Whether to strip [Image: ...] tags
• clean_for_vellum: Apply Vellum-specific formatting

Requirements

• Python 3.x
• pandoc (for .docx conversion)

Handling Complex Manuscripts

For manuscripts with special requirements (Notion exports, external images, nested chapters), create a book-specific preprocessing script. See Personal/Guide Abrege/prep_guide_abrege.py for an example that handles:

Notion Export Issues

• Missing image folders: Notion exports reference FolderName/image.png but don't always include the folder
• Substack CDN images: Can be downloaded with curl and remapped to local paths
• Image mapping pattern:

``python IMAGE_MAP = { "substack-uuid_dimensions.png": "images/01-descriptive-name.png", } ``

Nested Chapter Headings

When a document has nested "CHAPTER I/II/III" within sections (e.g., each movement family has its own Chapter I, II, III):

• Keep top-level sections as # (Vellum chapters)
• Demote internal "CHAPTER X:" labels to ## subheadings
• Strip the "CHAPTER X:" prefix, keep just the descriptive title

Tables

• Multi-line cells in markdown tables don't convert well via pandoc - convert to numbered lists instead
• See prep_guide_abrege.py for regex pattern to match and replace specific tables

Bold Labels as Headings

Instructional books often use **FIRST TYPE:** or **Method A:** as implicit subheadings. Convert these to actual headings (####) for proper Vellum hierarchy.

Workflow for Complex Books

1. Run exploratory agent to analyze structure
2. Create book-specific prep script
3. Download/remap external images
4. Run prep script → intermediate .md
5. Run pandoc directly (not vellum_prep.py) to preserve images
6. Review in Vellum, fix Parts/special elements manually

Files

• SKILL.md - This file
• vellum_prep.py - Main conversion script (OCR cleanup focus)

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: cdeistopened
• Source: cdeistopened/content-os
• License: MIT

Install and usage instructions live in the source repository linked above.