back
loading skill details...
Create and manipulate PDF files programmatically. Use when the user needs to generate PDFs, fill PDF forms, extract PDF content, add watermarks/overlays, or…
PDF Generator
When to Use This Skill
Use this skill when:
Creating PDF documents programmatically from data or specifications
Filling PDF forms with dynamic data
Adding watermarks, stamps, or overlays to existing PDFs
Extracting text and metadata from PDF files
Merging multiple PDFs into one document
Analyzing PDF structure and form fields
Do NOT use this skill when:
User wants to open/view PDFs (use native PDF viewer)
Complex page layout with flowing text is needed (consider HTML-to-PDF tools)
Working with password-protected PDFs (limited support)
OCR is needed for scanned documents
Prerequisites
Deno installed (https://deno.land/)
Input PDF files for template-based operations
JSON specification for scratch generation
Quick Start
Two Modes of Operation
Template Mode: Modify existing PDF templates
Fill form fields (text, checkbox, dropdown)
Add overlays (text, images, shapes)
Merge and combine PDFs
Scratch Mode: Create PDFs from nothing using JSON specifications
Instructions
Mode 1: Template-Based Generation
Step 1a: Analyze the Template
Extract form fields and structure from an existing PDF:
deno run --allow-read scripts/analyze-template.ts form-template.pdf > inventory.json
Output (inventory.json):
{
"filename": "form-template.pdf",
"pageCount": 2,
"title": "Application Form",
"author": "Company Inc",
"pages": [
{ "pageNumber": 1, "width": 612, "height": 792, "text": "..." }
],
"formFields": [
{ "name": "FullName", "type": "text", "value": "" },
{ "name": "Email", "type": "text", "value": "" },
{ "name": "AgreeToTerms", "type": "checkbox", "value": false }
],
"placeholders": [
{ "tag": "{{DATE}}", "location": "page 1", "pageNumber": 1 }
],
"hasFormFields": true
}
Step 1b: Create Fill Specification
Create form-data.json:
{
"formFields": [
{ "name": "FullName", "value": "John Smith" },
{ "name": "Email", "value": "john@example.com" },
{ "name": "AgreeToTerms", "value": true }
],
"flattenForm": true
}
Step 1c: Generate Filled PDF
deno run --allow-read --allow-write scripts/generate-from-template.ts \
form-template.pdf form-data.json filled-form.pdf
Adding Overlays (Watermarks, Stamps)
Create watermark-spec.json:
{
"overlays": [
{
"type": "text",
"page": 1,
"x": 200,
"y": 400,
"text": "CONFIDENTIAL",
"fontSize": 48,
"color": { "r": 1, "g": 0, "b": 0 },
"rotate": 45
},
{
"type": "image",
"page": 1,
"x": 450,
"y": 700,
"path": "logo.png",
"width": 100,
"height": 50
}
]
}
Merging PDFs
Create merge-spec.json:
{
"prependPdfs": [
{ "path": "cover-page.pdf" }
],
"appendPdfs": [
{ "path": "appendix-a.pdf", "pages": [1, 2, 3] },
{ "path": "appendix-b.pdf" }
],
"excludePages": [5, 6]
}
Mode 2: From-Scratch Generation
Step 2a: Create Specification
Create spec.json:
{
"title": "Quarterly Report",
"author": "Finance Team",
"pages": [
{
"size": "A4",
"elements": [
{
"type": "text",
"x": 50,
"y": 750,
"text": "Q4 2024 Financial Report",
"fontSize": 28,
"font": "HelveticaBold",
"color": { "r": 0, "g": 0, "b": 0.5 }
},
{
"type": "line",
"startX": 50,
"startY": 740,
"endX": 550,
"endY": 740,
"thickness": 2
},
{
"type": "text",
"x": 50,
"y": 700,
"text": "Executive Summary",
"fontSize": 18,
"font": "HelveticaBold"
},
{
"type": "text",
"x": 50,
"y": 670,
"text": "This quarter showed strong growth across all divisions...",
"fontSize": 12,
"maxWidth": 500,
"lineHeight": 16
}
]
}
]
}
Step 2b: Generate PDF
deno run --allow-read --allow-write scripts/generate-scratch.ts spec.json output.pdf
Examples
Example 1: Fill Application Form
Scenario: Automatically fill a job application form.
# 1. Analyze form to find field names
deno run --allow-read scripts/analyze-template.ts application.pdf --pretty
# 2. Create form-data.json with applicant info
# 3. Generate filled form
deno run --allow-read --allow-write scripts/generate-from-template.ts \
application.pdf form-data.json john-smith-application.pdf
Example 2: Add Approval Stamp
Scenario: Add an "APPROVED" stamp to a document.
stamp-spec.json:
{
"overlays": [
{
"type": "rectangle",
"page": 1,
"x": 400,
"y": 700,
"width": 150,
"height": 50,
"color": { "r": 0.9, "g": 1, "b": 0.9 }
},
{
"type": "text",
"page": 1,
"x": 410,
"y": 720,
"text": "APPROVED",
"fontSize": 20,
"font": "HelveticaBold",
"color": { "r": 0, "g": 0.5, "b": 0 }
},
{
"type": "text",
"page": 1,
"x": 410,
"y": 705,
"text": "2024-12-15",
"fontSize": 10
}
]
}
Example 3: Create Report with Table
Scenario: Generate a simple report with a data table.
report-spec.json:
{
"title": "Sales Report",
"pages": [{
"size": "Letter",
"elements": [
{
"type": "text",
"x": 72,
"y": 720,
"text": "Monthly Sales Report",
"fontSize": 24,
"font": "HelveticaBold"
},
{
"type": "table",
"x": 72,
"y": 680,
"rows": [
["Product", "Units", "Revenue"],
["Widget A", "150", "$15,000"],
["Widget B", "75", "$11,250"],
["Widget C", "200", "$8,000"]
],
"columnWidths": [150, 80, 100],
"rowHeight": 25,
"headerBackground": { "r": 0.9, "g": 0.9, "b": 0.9 }
}
]
}]
}
Script Reference
Script
Purpose
Permissions
analyze-template.ts
Extract text, metadata, form fields from PDF
--allow-read
generate-from-template.ts
Fill forms, add overlays, merge PDFs
--allow-read --allow-write
generate-scratch.ts
Create PDF from JSON specification
--allow-read --allow-write
Element Types (Scratch Mode)
Type
Description
Key Options
text
Text content
x, y, text, fontSize, font, color, rotate
image
PNG/JPEG images
x, y, path, width, height, opacity
rectangle
Filled/outlined rectangles
x, y, width, height, color, borderColor
line
Straight lines
startX, startY, endX, endY, thickness
circle
Filled/outlined circles
x, y, radius, color, borderColor
table
Basic table layout
x, y, rows, columnWidths, rowHeight
Available Fonts
Helvetica (default)
HelveticaBold
HelveticaOblique
TimesRoman
TimesBold
Courier
CourierBold
Page Sizes
A4 (595.28 x 841.89 points)
Letter (612 x 792 points)
Legal (612 x 1008 points)
Custom: [width, height] in points
Common Issues and Solutions
Issue: Form fields not found
Symptoms: Error saying field name doesn't exist.
Solution:
Run analyze-template.ts to get exact field names
Field names are case-sensitive
Some PDFs have non-fillable text that looks like form fields
Issue: Text positioning is off
Symptoms: Text appears in wrong location.
Solution:
PDF coordinates start from bottom-left (0,0)
Y increases upward, X increases rightward
Use analyze-template.ts to see page dimensions
Issue: Images not appearing
Symptoms: Image overlay not visible.
Solution:
Check file path is relative to spec.json location
Verify image is PNG or JPEG format
Ensure coordinates are within page bounds
Issue: Merged PDF has wrong page order
Symptoms: Pages appear in unexpected order.
Solution:
prependPdfs add pages before template
appendPdfs add pages after template
Use pages array to select specific pages: [1, 3, 5]
Limitations
No built-in table layout: Tables require manual column width specification
Standard fonts only: Custom font embedding not supported in scratch mode
No flowing text: Text doesn't automatically wrap to next page
Limited form field creation: Can fill existing forms, not create new fields
No encryption: Cannot create password-protected PDFs
Basic graphics: No gradients, patterns, or complex paths
Text extraction: May not work perfectly on all PDFs (depends on PDF structure)
Related Skills
pptx-generator: For creating PowerPoint presentations
docx-generator: For creating Word documents
xlsx-generator: For creating Excel spreadsheetsdon't have the plugin yet? install it then click "run inline in claude" again.