Preview D3 Skill

Interactive D3.js visualization viewer that renders custom data visualizations with built-in zoom, pan, and export capabilities.

Agent Usage

When the user asks to create a D3 visualization, write the D3 code and pipe it to the script. Use the Bash tool to execute this skill's run.sh script:

# Pipe D3 code
cat visualization.js | ./run.sh

# Or from a file
./run.sh chart.d3

The script handles all HTML generation and automatically opens the result in the browser. Do NOT open the file manually to avoid duplicate tabs.

Usage

# Preview a D3 visualization file
/preview-d3 network-graph.d3

# Pipe D3 code (preferred for temporary content)
cat visualization.js | /preview-d3
echo "const svg = d3.select('#visualization').append('svg')..." | /preview-d3

Best Practice: For temporary or generated visualizations, prefer piping over creating temporary files. This avoids cluttering your filesystem and the content is automatically cleaned up.

Options

The script works with sensible defaults but supports these flags for flexibility:

• -o, --output PATH - Custom output path
• --no-browser - Skip browser, output file path only

Features

• Universal D3 compatibility - Works with any D3 code from the web
• Zoom and pan - Mouse wheel to zoom (0.5x to 10x), drag to pan
• Reset zoom button
• Code viewer toggle
• Export to SVG functionality
• Preserves interactions - Tooltips, draggable nodes, animations all work
• Automatic container detection - Works with any selector
• Responsive design adapts to screen size

When to Use This Skill

Use this skill when the user wants to:

• Create custom data visualizations
• Render charts, graphs, and network diagrams
• Visualize hierarchical data
• Create interactive dashboards
• Test D3 code snippets from online examples

D3 Code Requirements

Your D3 code should be self-contained JavaScript that:

1. Gets container dimensions from the DOM
2. Creates its own SVG element
3. Handles tooltips directly (if needed)
4. Embeds data in the code

Code Template

// Get container dimensions
const container = document.querySelector('#visualization');
const rect = container.getBoundingClientRect();
const width = rect.width;
const height = rect.height;
const margin = { top: 60, right: 40, bottom: 60, left: 60 };
const innerWidth = width - margin.left - margin.right;
const innerHeight = height - margin.top - margin.bottom;

// Sample data
const data = [
  { category: 'A', value: 30 },
  { category: 'B', value: 80 },
  { category: 'C', value: 45 },
];

// Create SVG
const svg = d3.select('#visualization').append('svg').attr('width', width).attr('height', height);

const chart = svg.append('g').attr('transform', `translate(${margin.left},${margin.top})`);

// Create scales, axes, and visualization elements
// Your D3 code here...

Complete Example - Bar Chart

//Get container dimensions
const container = document.querySelector('#visualization');
const rect = container.getBoundingClientRect();
const width = rect.width;
const height = rect.height;
const margin = { top: 60, right: 40, bottom: 60, left: 60 };
const innerWidth = width - margin.left - margin.right;
const innerHeight = height - margin.top - margin.bottom;

// Sample data
const data = [
  { category: 'A', value: 30 },
  { category: 'B', value: 80 },
  { category: 'C', value: 45 },
  { category: 'D', value: 60 },
  { category: 'E', value: 20 },
];

// Create SVG
const svg = d3.select('#visualization').append('svg').attr('width', width).attr('height', height);

const chart = svg.append('g').attr('transform', `translate(${margin.left},${margin.top})`);

// Scales
const xScale = d3
  .scaleBand()
  .domain(data.map((d) => d.category))
  .range([0, innerWidth])
  .padding(0.2);

const yScale = d3
  .scaleLinear()
  .domain([0, d3.max(data, (d) => d.value)])
  .nice()
  .range([innerHeight, 0]);

// Axes
chart.append('g').attr('transform', `translate(0,${innerHeight})`).call(d3.axisBottom(xScale));

chart.append('g').call(d3.axisLeft(yScale));

// Bars with tooltip
const tooltip = d3
  .select('body')
  .append('div')
  .attr('class', 'd3-tooltip')
  .style('position', 'absolute')
  .style('opacity', 0);

chart
  .selectAll('rect')
  .data(data)
  .join('rect')
  .attr('x', (d) => xScale(d.category))
  .attr('y', (d) => yScale(d.value))
  .attr('width', xScale.bandwidth())
  .attr('height', (d) => innerHeight - yScale(d.value))
  .attr('fill', '#3498db')
  .on('mouseover', (event, d) => {
    tooltip.transition().duration(200).style('opacity', 1);
    tooltip
      .html(`<strong>${d.category}</strong><br/>Value: ${d.value}`)
      .style('left', event.pageX + 10 + 'px')
      .style('top', event.pageY - 10 + 'px');
  })
  .on('mouseout', () => {
    tooltip.transition().duration(200).style('opacity', 0);
  });

// Title
chart
  .append('text')
  .attr('x', innerWidth / 2)
  .attr('y', -20)
  .attr('text-anchor', 'middle')
  .style('font-size', '18px')
  .style('font-weight', 'bold')
  .text('Sample Bar Chart');

Common Patterns

Line Chart

const line = d3
  .line()
  .x((d) => xScale(d.date))
  .y((d) => yScale(d.value));

svg
  .append('path')
  .datum(data)
  .attr('fill', 'none')
  .attr('stroke', '#3498db')
  .attr('stroke-width', 2)
  .attr('d', line);

Scatter Plot

svg
  .selectAll('circle')
  .data(data)
  .join('circle')
  .attr('cx', (d) => xScale(d.x))
  .attr('cy', (d) => yScale(d.y))
  .attr('r', 5)
  .attr('fill', '#3498db');

Pie Chart

const pie = d3.pie().value((d) => d.value);
const arc = d3.arc().innerRadius(0).outerRadius(radius);

svg
  .selectAll('path')
  .data(pie(data))
  .join('path')
  .attr('d', arc)
  .attr('fill', (d, i) => d3.schemeCategory10[i]);

Execution Context

Your code runs with:

• D3.js v7 library available as d3
• Container element #visualization ready in the DOM
• Zoom and pan automatically added to your SVG

Built-in Features

• Zoom - Mouse wheel (0.5x to 10x range)
• Pan - Click and drag on background
• Reset View - Button to reset zoom/pan
• Code Viewer - Toggle to show/hide source code
• Export SVG - Download visualization as SVG file

Best Practices

1. Use relative sizing - Get dimensions from container element
2. Include margins - Leave space for axes and labels
3. Create tooltips - Append div to body with position: absolute
4. Embed data - Include data in the code file
5. Test in console - Verify code works before saving

Troubleshooting

Visualization doesn't appear

• Check browser console (F12) for JavaScript errors
• Verify SVG element is created in DOM inspector
• Check that selector matches (#visualization)
• Ensure data is valid

Elements in wrong position

• Check transform attributes and translations
• Verify scales have correct domain and range
• Ensure margins are applied consistently

Tooltips don't work

• Append tooltip div to body, not SVG
• Use position: absolute CSS
• Use event.pageX/pageY for positioning (not clientX/Y)

Data doesn't load

• Embed data directly in code (no external files)
• Verify data format matches visualization expectations

Technical Details

File Requirements

• File extension: .d3
• Maximum size: 10MB (configurable)
• Valid JavaScript code
• Self-contained (no external dependencies)

Browser Compatibility

• Modern browsers (Chrome, Firefox, Safari, Edge)
• Requires JavaScript enabled
• CDN-dependent: D3.js v7 library

Output

The skill generates a standalone HTML file at:

/tmp/preview-skills/preview-d3-{filename}.html

Development

This skill is standalone and includes all dependencies:

• Shared libraries bundled in lib/
• Templates bundled in templates/
• External CDN dependencies: D3.js v7

To modify the skill:

1. Edit config.sh for configuration
2. Edit templates/scripts/d3-renderer.js for behavior
3. Edit templates/styles/d3.css for styling
4. Run run.sh to test changes

Learn More

• D3.js Gallery: https://observablehq.com/@d3/gallery
• D3.js Documentation: https://d3js.org/
• Examples: https://github.com/d3/d3/wiki/Gallery