Vela Slides Skill
v2.6.0 · 2026-03-23 · CLI optimizations (split, dump, stats, find, extract-text/patch-text), 82 tests, live serve with long-polling
Generate presentation-ready slide decks and assemble them into runnable Vela .jsx artifacts. Also supports modular editing of the Vela app itself.
When to Use
- User wants to create a slide deck / presentation
- User provides a topic, agenda, outline, or document to turn into slides
- User wants to restyle or improve existing Vela slide JSON
- User wants to fix bugs or add features to the Vela app itself
- User asks for "Vela slides", "deck", or "presentation" content
Fast Paths (check FIRST — skip references if your task matches)
Load/ship an existing deck JSON
python3 skills/vela-slides/scripts/vela.py deck ship <deck.json> --output <name.jsx>
Total: 1 CLI call → done. No references needed.
Load with sample deck (no source file)
python3 skills/vela-slides/scripts/vela.py deck ship --sample --output <name.jsx>
Total: 1 CLI call → done. No references needed.
Extract deck from an existing .jsx artifact
python3 skills/vela-slides/scripts/vela.py deck extract <source.jsx> <output.json>
python3 skills/vela-slides/scripts/vela.py deck ship <output.json> --output <name.jsx>
Total: 2 CLI calls → done. No references needed.
Edit an existing deck → skip to Workflow A½ below
Create a new deck → continue to Workflow A below (read references/block-schema.md + design-patterns.md)
References (load on demand)
references/block-schema.md— Read when creating a new deck or adding unfamiliar block typesreferences/design-patterns.md— Read when designing a deck from scratch (archetypes, anti-patterns, density rules)references/themes.md— Read when user asks about theming, restyling, or brand customizationreferences/formats.md— Read when you need turbo format details, conversion commands, or benchmarksreferences/app-editing.md— Read when editing the Vela app itself (part-files, concat, template)
Vela CLI Setup
The vela CLI is a single entry point for all deck operations. Setup depends on environment:
Claude.ai artifacts (skill mounted at /mnt/skills/):
# Call directly — do NOT use ln -sf (symlinks inherit read-only perms)
python3 /mnt/skills/user/vela-slides/scripts/vela.py <resource> <action> [args...]
Claude Code (local project): call the script directly — no symlink needed:
python3 skills/vela-slides/scripts/vela.py <resource> <action> [args...]
# Or create an alias for the session:
alias vela='python3 /path/to/skills/vela-slides/scripts/vela.py'
Discovery (zero turns wasted):
vela --capabilities # JSON index of all commands, flags, exit codes
vela --help # Human-readable overview
Formats
Vela supports three JSON formats (full, compact, turbo). All CLI commands auto-detect and auto-expand. For conversion commands, turbo details, and benchmarks, read references/formats.md.
Compact Format (use when generating decks)
Always generate in compact format — saves ~32% output tokens. Short keys, flat slides array, theme presets, spacer shorthand, color palette aliases. The CLI auto-expands on ship/validate.
Compact key reference
Top-level: n=deckTitle, T=themes, C=color palette, S=slides array
Slide level: t=theme ref, n=title, d=duration, B=blocks, p=padding (only if overriding theme)
Block level: _=type, x=text, s=size, c=color, i=icon, b=bg, w=weight, ic=iconColor, ib=iconBg, I=items, B=blocks (nested), g=gap, lb=label, v=variant, H=headers, R=rows, sl=sublabel, slc=sublabelColor, ac=arrowColor, lc=labelColor, ts=titleSize, xs=textSize, hb=headerBg, hc=headerColor, cc=cellColor, bc=borderColor, str=striped, lo=loop, lnc=lineColor, nc=numberColor, tc=titleColor, xc=textColor, dc=dotColor, cir=circle, dir=direction
Color palette (C): define every color used ≥2× as "$A":"#hex". Use $A everywhere instead of raw hex. Assign in frequency order ($A = most common).
Theme palette (T): "d":dark, "l":light, "a":alt. Keys: b=bg, c=color, a=accent, p=padding. Theme values can use $ aliases too.
Spacers: bare int 8 instead of {"_":"spacer","h":8}
Note: v maps to variant, NOT value. For block-specific properties without a compact alias (e.g., value, cols, bgGradient, align, verticalAlign, gateIcon, dateColor), use the full property name — the CLI expands them correctly.
Workflow A: Generate a Deck (most common)
Step 1: Generate Compact JSON
Rules for generating compact:
- Top-level:
{"n":"Title","T":{themes},"C":{color palette},"S":[slides]} - Color palette (
C): define every color used 2+ times as$A,$B, etc. Use these aliases everywhere in the deck instead of raw hex/rgba values. - Themes (
T): group slides by bg/color/accent/padding."d"= dark,"l"= light,"a"= alt. - Slides (
S): flat array. Each slide has"t":"d"(theme ref),"n"(title),"d"(duration),"B"(blocks). - Blocks: use short keys (
_=type,x=text,s=size,c=color,i=icon,b=bg, etc.) - Spacers: just the int
8instead of{"_":"spacer","h":8} - Minified: no whitespace, no indentation.
Complete example (3-slide compact deck)
{"n":"AI Workshop","C":{"$A":"#3B82F6","$B":"#E6F1FF","$C":"#8892B0","$D":"#0A0F1C","$E":"#3B82F620","$F":"#1e293b"},"T":{"d":{"b":"$D","c":"$B","a":"$A","p":"60px 72px"},"l":{"b":"#ffffff","c":"$F","a":"$A","p":"36px 48px"}},"S":[{"t":"d","n":"Cover","d":15,"B":[{"_":"badge","x":"WORKSHOP","i":"GraduationCap","b":"$E","c":"$A"},8,{"_":"heading","x":"AI para Equipas","s":"3xl","w":700},{"_":"text","x":"Formação prática com LLMs e agentes.","s":"lg","c":"$C"}]},{"t":"l","n":"Agenda","d":60,"B":[{"_":"badge","x":"PROGRAMA","i":"Calendar","b":"$E","c":"$A"},8,{"_":"heading","x":"Agenda do Dia","s":"2xl"},{"_":"steps","I":[{"title":"09:00","x":"Fundamentos LLM"},{"title":"13:30","x":"Agentes e MCP"}],"lnc":"$A","nc":"$A","tc":"$F","xc":"#64748b"}]},{"t":"d","n":"CTA","d":20,"B":[{"_":"heading","x":"Vamos Construir?","s":"3xl","w":700},12,{"_":"text","x":"info@agentia.pt","s":"lg","c":"$C"}]}]}
Key patterns in the example:
$A=#3B82F6used 5× (badges, steps, accent) — saves ~16 tokens- Themes absorb bg/color/accent/padding — each slide just says
"t":"d"or"t":"l" - Spacers are bare ints:
8,12 - Steps items use
"title"and"x"(text) - Everything minified on one line
Step 2: Ship (validate + assemble + deliver)
vela deck ship /home/claude/<deck-name>-slides.json
This runs expand → validate → assemble → copy in one call.
Output defaults to current working directory. Override with --output:
vela deck ship deck.json --output /path/to/output.jsx
Or set VELA_OUTPUT_DIR environment variable to change the default.
Step 3: Present
present_files(["/mnt/user-data/outputs/<deck>.jsx", "/mnt/user-data/outputs/<deck>-slides.json"])
CLI Quick Reference (v2.6.0)
vela deck — Deck-level operations (auto-detects full/compact/turbo format)
vela deck list <deck.json> — TOC with slide#, title, blocks, duration
vela deck validate <deck.json> — check deck JSON integrity
vela deck split <deck.json> --sections "Title:N,..." | --flat | --size N — regroup slides into sections (--flat to merge all into one)
vela deck assemble <deck.json> [--output <path>] — inject deck into JSX artifact
vela deck ship <deck.json> [--output <path>] — validate + assemble in one call
vela deck replace-text <deck.json> "old" "new" — find/replace across all slides (hex colors auto-cascade to rgba)
vela deck stats <deck.json> — health audit: block distribution, missing durations, overflow, monotony issues
vela deck find <deck.json> --query "text" | --type flow | --missing duration — search slides by content, block type, or missing props
vela deck dump <deck.json> [--full] — compact text-only view of all slides (--full for all text fields)
vela deck extract-text <deck.json> [output.json] — extract all translatable text as key-value map
vela deck patch-text <deck.json> <texts.json> — apply translated text map back into deck
vela deck expand <compact.json> <full.json> — compact/turbo → full format
vela deck compact <full.json> <compact.json> — full → compact format
vela deck turbo <deck.json> <turbo.json> — any → turbo format
vela deck serve <deck.json> [--port N] — live preview with two-way sync
vela slide — Slide-level operations (1-indexed slide numbers)
vela slide view <deck.json> <N> — show slide content summary
vela slide edit <deck.json> <N> <key> <value> — edit slide/block property (block.I.key for blocks)
vela slide remove <deck.json> <N> — remove a slide
vela slide move <deck.json> <from> <to> — reorder a slide
vela slide duplicate <deck.json> <N> — copy a slide
vela slide insert <deck.json> <N> <slide.json> — insert slide from file
vela slide remove-block <deck.json> <N> <block#> — remove a block from a slide
Global flags: --json (structured output), --dry-run (preview without writing), --help
Exit codes: 0=success, 1=failure, 2=usage error, 3=not found, 4=validation error, 5=conflict
Workflow A½: Edit an Existing Deck
Use the vela CLI instead of view + str_replace — saves 80-97% tokens on typical edits.
Inspect
vela deck list deck.json # TOC: slide#, title, blocks, theme, duration
vela slide view deck.json 3 # Compact block summary
vela slide view deck.json 3 --raw # Full JSON for one slide
vela slide view deck.json 3 --json # Structured output for agent consumption
Edit
# Text replacement across entire deck (idempotent)
vela deck replace-text deck.json "old text" "new text"
# Slide-level property
vela slide edit deck.json 3 duration 90
vela slide edit deck.json 3 bg "#ffffff"
# Block-level property (use block.INDEX.KEY syntax)
vela slide edit deck.json 3 block.2.text "New heading"
vela slide edit deck.json 3 block.0.color "#3B82F6"
# Structural operations
vela slide remove deck.json 4
vela slide remove-block deck.json 3 5
vela slide move deck.json 5 2
vela slide duplicate deck.json 2
vela slide insert deck.json 3 new-slide.json
Validate After Edits
# Always validate after editing
vela deck validate deck.json --json # check for errors
# Fix reported issues, then re-validate until exit code 0
# Use --dry-run before destructive operations (remove, move, replace-text)
vela slide remove deck.json 3 --dry-run
# Returns: {"would_execute": "remove_slide", "title": "...", "reversible": false}
To build the final runnable artifact (rare — only when user wants the .jsx):
vela deck ship deck.json # validate + assemble + copy in one call
When to use what
| Task | Command | Why |
|---|---|---|
| Translate / bulk text rewrite | extract-text + patch-text |
2 calls vs N×replace-text |
| Change a word/phrase everywhere | vela deck replace-text |
1 call vs N×str_replace |
| Change one slide property | vela slide edit N key value |
No need to view JSON first |
| Change one block property | vela slide edit N block.I.key value |
Precise, zero collateral |
| Remove/reorder slides | vela slide remove/move |
Clean item-level removal |
| Split into sections | vela deck split --sections "A:3,B:5" |
One call, agent decides grouping |
| Flatten to one module | vela deck split --flat |
Merge all sections into one |
| Regroup sections | vela deck split --sections "..." |
Works on multi-module decks (flattens first) |
| Check what slides exist | vela deck list |
~200 tokens vs ~800 for view |
| Check one slide | vela slide view N |
~150 tokens vs ~500 for view+range |
| Preview before destructing | Add --dry-run |
Agent safety net |
| Full pipeline | vela deck ship |
Replaces 3-4 tool calls with 1 |
| Rewrite a slide entirely | vela slide view N --raw → str_replace |
Still best for full rewrites |
| Complex block structure changes | str_replace on JSON |
CLI handles properties, not deep nesting |
Workflow B & C: Edit the Vela App
For app editing and updating, read
references/app-editing.md.
Deck JSON Format
Full Deck (for assembly)
{
"deckTitle": "My Presentation",
"lanes": [
{
"title": "Main",
"items": [
{
"title": "Section Name",
"status": "todo",
"importance": "must",
"slides": [ ...slide objects... ]
}
]
}
]
}
Single Slide
{
"bg": "#0f172a",
"bgGradient": "linear-gradient(135deg, #0f172a 0%, #1e293b 100%)",
"color": "#e2e8f0",
"accent": "#3b82f6",
"padding": "36px 48px",
"duration": 60,
"blocks": [ ... ]
}
Critical Rules
Canvas
- Virtual canvas: 960x540px (16:9)
- Base padding:
"36px 48px"— never less - Max 5-7 blocks per slide
- Left-aligned = full width. Center-aligned = shrink-wrap.
Duration
- Every slide MUST have
duration(integer, seconds) - Title: 15-30s | Content: 60-90s | Dense: 90-180s | Metric: 20-40s | Quote: 15-30s
Visual Design
- Every slide MUST have
bgorbgGradient - Size hierarchy:
3xl-4xltitles >2xlheadings >lgbody >mdsupporting >smcaptions - Use icons generously. Use
spacerblocks for breathing room. - First slide = title (centered, gradient, 4xl). Last slide = closing (gradient, strong visual).
- Vary bg across slides — alternate solid/gradient, shift hues for section breaks.
Block Selection
- Don't default to heading+bullets — vary layouts across slides
icon-row> plain bullets for feature listsflowfor processes |flow loop:truefor cycles |flow gate:truefor approvalssvgfor custom diagrams (use{{accent}},{{color}},{{muted}},{{bg}}tokens)grid2-3 cols for comparisons |grid1 col +direction:"row"for layer diagramsmetricfor stats |tablefor structured data |progressfor bars/spectrumsstepsfor numbered sequences |timelinefor roadmaps |tag-groupfor labelscalloutwith icon for key insights
Content Quality
- One key idea per slide. Billboard test — readable from the back.
- Headlines = assertions ("AI Cuts Costs 30%"), not labels ("Cost Analysis")
- Default slide count: if user gives no outline, default to 6-8 slides. If they provide N topics, use N+2 (cover + closing).
- Invent plausible content when the user provides a topic but no specifics. Never use placeholder brackets like
[Your Name].
Gotchas
align: "center"+ SVG/divider/progress = invisible blocks. These blocks have no intrinsic width and collapse to zero. Usealign: "left"at slide level + per-block"align": "center". For SVG blocks, add"maxWidth": "60%"+"align": "center"on the block itself.- Duration is required on every slide — there is no default. Omitting it causes validation failure.
- Color palette
$Aaliases must be defined inCbefore use. Undefined aliases render as literal text. - Canvas is 960x540px — block coordinates and sizes must stay within these limits.
- Compact spacers are bare ints —
8not{"_":"spacer","h":8}. Generating the object form wastes tokens. - Removing multiple slides? Remove from highest index first to avoid re-indexing shifting which slide gets removed.
Theming
See references/themes.md for palettes. Available directions: dark, midnight, light, warm light, vibrant, editorial, minimal. Custom brand colors supported.
Icons
PascalCase Lucide names. 1000+ available. Common: Zap, Brain, Rocket, Shield, Target, Clock, Users, Heart, Globe, Code, Database, Lightbulb, TrendingUp, BarChart, Lock, Eye, Cpu, Layers, Bot, Sparkles, Award, CheckCircle, AlertTriangle, DollarSign, ArrowRight