Vela Slides

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

References (load on demand)

• references/block-schema.md — Read when creating a new deck or adding unfamiliar block types
• references/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 customization
• references/formats.md — Read when you need turbo format details, conversion commands, or benchmarks
• references/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/):

export PATH="/home/claude/.local/bin:$PATH"
ln -sf /mnt/skills/user/vela-slides/scripts/vela.py /home/claude/.local/bin/vela

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:

1. Top-level: {"n":"Title","T":{themes},"C":{color palette},"S":[slides]}
2. 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.
3. Themes (T): group slides by bg/color/accent/padding. "d" = dark, "l" = light, "a" = alt.
4. Slides (S): flat array. Each slide has "t":"d" (theme ref), "n" (title), "d" (duration), "B" (blocks).
5. Blocks: use short keys (_=type, x=text, s=size, c=color, i=icon, b=bg, etc.)
6. Spacers: just the int 8 instead of {"_":"spacer","h":8}
7. 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 = #3B82F6 used 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

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 bg or bgGradient
• Size hierarchy: 3xl-4xl titles > 2xl headings > lg body > md supporting > sm captions
• Use icons generously. Use spacer blocks 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 lists
• flow for processes | flow loop:true for cycles | flow gate:true for approvals
• svg for custom diagrams (use {{accent}}, {{color}}, {{muted}}, {{bg}} tokens)
• grid 2-3 cols for comparisons | grid 1 col + direction:"row" for layer diagrams
• metric for stats | table for structured data | progress for bars/spectrums
• steps for numbered sequences | timeline for roadmaps | tag-group for labels
• callout with 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. Use align: "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 $A aliases must be defined in C before use. Undefined aliases render as literal text.
• Canvas is 960x540px — block coordinates and sizes must stay within these limits.
• Compact spacers are bare ints — 8 not {"_":"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