Editing Presentations

Template-Based Workflow

When using an existing presentation as a template:

Copy and analyze:

bash

cp /path/to/user-provided.pptx template.pptx
python -m markitdown template.pptx > template.md

Review

template.md

to see placeholder text and slide structure.

Plan slide mapping: For each content section, choose a template slide.

⚠️ USE VARIED LAYOUTS — monotonous presentations are a common failure mode. Don't default to basic title + bullet slides. Actively seek out:
- Multi-column layouts (2-column, 3-column)
- Image + text combinations
- Full-bleed images with text overlay
- Quote or callout slides
- Section dividers
- Stat/number callouts
- Icon grids or icon + text rows
Avoid: Repeating the same text-heavy layout for every slide.

Match content type to layout style (e.g., key points → bullet slide, team info → multi-column, testimonials → quote slide).
Unpack
Build presentation (do this yourself, not with subagents):
- Delete unwanted slides (remove from
```
<p:sldIdLst>
```
  )
- Duplicate slides you want to reuse (
```
add_slide.py
```
  )
- Reorder slides in
```
<p:sldIdLst>
```
- Complete all structural changes before step 5
Edit content: Update text in each
```
slide{N}.xml
```
. Use subagents here if available — slides are separate XML files, so subagents can edit in parallel.
Clean
Pack

Output Structure

Copy the user-provided file to

template.pptx

in cwd. This preserves the original and gives a predictable name for all downstream scripts.

bash

cp /path/to/user-provided.pptx template.pptx

text

./
├── template.pptx               # Copy of user-provided file (never modified)
├── template.md                 # markitdown extraction
├── unpacked/                   # Editable XML tree
└── edited.pptx                 # Final repacked deck

Minimum expected deliverable:

edited.pptx

Scripts

Script	Purpose
`unpack.py`	Extract and pretty-print PPTX
`add_slide.py`	Duplicate slide or create from layout
`clean.py`	Remove orphaned files
`pack.py`	Repack with validation

Removes slides not in

<p:sldIdLst>

, unreferenced media, orphaned rels.

Always write to

/tmp/

first, then copy to the final path. Python's

zipfile

module uses

seek

internally, which fails on some volume mounts (e.g. Docker bind mounts). Writing to a local temp path avoids this.

Validates, repairs, condenses XML, re-encodes smart quotes.

Slide Operations

Slide order is in

ppt/presentation.xml

→

<p:sldIdLst>

Reorder: Rearrange

<p:sldId>

elements.

Delete: Remove

<p:sldId>

, then run

clean.py

Add: Use

add_slide.py

. Never manually copy slide files—the script handles notes references, Content_Types.xml, and relationship IDs that manual copying misses.

Editing Content

Subagents: If available, use them here (after completing step 4). Each slide is a separate XML file, so subagents can edit in parallel. In your prompt to subagents, include:

The slide file path(s) to edit
"Use the Edit tool for all changes"
The formatting rules and common pitfalls below

For each slide:

Read the slide's XML
Identify ALL placeholder content—text, images, charts, icons, captions
Replace each placeholder with final content

Use the Edit tool, not sed or Python scripts. The Edit tool forces specificity about what to replace and where, yielding better reliability.

Formatting Rules

Bold all headers, subheadings, and inline labels: Use
```
b="1"
```
on
```
<a:rPr>
```
. This includes:
- Slide titles
- Section headers within a slide
- Inline labels like (e.g.: "Status:", "Description:") at the start of a line
Never use unicode bullets (•): Use proper list formatting with
```
<a:buChar>
```
or
```
<a:buAutoNum>
```
Bullet consistency: Let bullets inherit from the layout. Only specify
```
<a:buChar>
```
or
```
<a:buNone>
```
.

Common Pitfalls

Template Adaptation

When source content has fewer items than the template:

Remove excess elements entirely (images, shapes, text boxes), don't just clear text
Check for orphaned visuals after clearing text content
Run content QA with
```
markitdown
```
to catch mismatched counts

When replacing text with different length content:

Shorter replacements: Usually safe
Longer replacements: May overflow or wrap unexpectedly
Verify with
```
markitdown
```
after text changes
Consider truncating or splitting content to fit the template's design constraints

Template slots ≠ Source items: If template has 4 team members but source has 3 users, delete the 4th member's entire group (image + text boxes), not just the text.

Multi-Item Content

If source has multiple items (numbered lists, multiple sections), create separate

<a:p>

elements for each — never concatenate into one string.

❌ WRONG — all items in one paragraph:

xml

<a:p>
  <a:r><a:rPr .../><a:t>Step 1: Do the first thing. Step 2: Do the second thing.</a:t></a:r>
</a:p>

✅ CORRECT — separate paragraphs with bold headers:

xml

<a:p>
  <a:pPr algn="l"><a:lnSpc><a:spcPts val="3919"/></a:lnSpc></a:pPr>
  <a:r><a:rPr lang="en-US" sz="2799" b="1" .../><a:t>Step 1</a:t></a:r>
</a:p>
<a:p>
  <a:pPr algn="l"><a:lnSpc><a:spcPts val="3919"/></a:lnSpc></a:pPr>
  <a:r><a:rPr lang="en-US" sz="2799" .../><a:t>Do the first thing.</a:t></a:r>
</a:p>
<a:p>
  <a:pPr algn="l"><a:lnSpc><a:spcPts val="3919"/></a:lnSpc></a:pPr>
  <a:r><a:rPr lang="en-US" sz="2799" b="1" .../><a:t>Step 2</a:t></a:r>
</a:p>
<!-- continue pattern -->

Copy

<a:pPr>

from the original paragraph to preserve line spacing. Use

b="1"

on headers.

Smart Quotes

Handled automatically by unpack/pack. But the Edit tool converts smart quotes to ASCII.

When adding new text with quotes, use XML entities:

xml

<a:t>the &#x201C;Agreement&#x201D;</a:t>

Character	Name	Unicode	XML Entity
`"`	Left double quote	U+201C	`“`
`"`	Right double quote	U+201D	`”`
`'`	Left single quote	U+2018	`‘`
`'`	Right single quote	U+2019	`’`

Other

Whitespace: Use
```
xml:space="preserve"
```
on
```
<a:t>
```
with leading/trailing spaces
XML parsing: Use
```
defusedxml.minidom
```
, not
```
xml.etree.ElementTree
```
(corrupts namespaces)

ppt-editing-skill

NPX Install

Tags

SKILL.md Content