name: dbpedia-query-skill
description: Transform natural language questions into SPARQL queries for DBpedia and generate beautiful HTML results pages. Query the DBpedia knowledge graph using plain English prompts.

DBpedia Query Skill

When to Use This Skill

Use this skill when users want to:

• Query DBpedia using natural language
• Ask questions about people, places, movies, books, organizations, etc.
• Get structured data from Wikipedia via DBpedia
• Create visualizations of DBpedia query results
• Generate HTML reports from SPARQL queries

Core Capabilities

✅ Natural Language to SPARQL: Convert user questions into valid SPARQL queries
✅ Query Execution: Execute queries against DBpedia endpoint
✅ HTML Generation: Create beautiful, interactive HTML result pages
✅ Multiple Output Formats: JSON, Markdown tables, or HTML
✅ Error Handling: Graceful handling of malformed queries or no results

DBpedia Endpoint

SPARQL Endpoint: https://dbpedia.org/sparql
Format: JSON results (format=json)
Method: HTTP GET with URL-encoded query

Common DBpedia Prefixes

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX dbp: <http://dbpedia.org/property/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX dct: <http://purl.org/dc/terms/>

Query Conversion Workflow

When a user provides a natural language prompt:

1. Analyze the Question

• Identify the subject (who/what is being asked about)
• Identify the predicate (what information is requested)
• Determine if filtering, sorting, or limiting is needed

2. Map to DBpedia Properties

Common mappings:

• "directed by" → dbo:director
• "release date" → dbp:date or dbo:releaseDate
• "budget" → dbo:budget
• "born in" → dbo:birthPlace
• "population" → dbo:populationTotal
• "capital of" → dbo:capital
• "written by" → dbo:author
• "starring" → dbo:starring

3. Construct SPARQL Query

Template:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT DISTINCT ?variable ?label
WHERE {
  ?variable <predicate> <object> ;
           rdfs:label ?label .
  FILTER(LANG(?label) = 'en')
}
ORDER BY <sort_criteria>
LIMIT <number>

4. Execute Query

Use curl to execute against DBpedia:

curl -s -G "https://dbpedia.org/sparql" \
  --data-urlencode "query=<SPARQL_QUERY>" \
  --data-urlencode "format=json"

5. Generate Output

Options:

• JSON: Raw query results
• Markdown Table: Formatted for terminal display
• HTML Page: Interactive, styled results page

Example Query Patterns

Pattern 1: Films by Director

User: "Show me movies directed by Christopher Nolan"

SPARQL:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT DISTINCT ?film ?title ?releaseDate
WHERE {
  ?film dbo:director dbr:Christopher_Nolan ;
        a dbo:Film ;
        rdfs:label ?title .
  OPTIONAL { ?film dbo:releaseDate ?releaseDate }
  FILTER(LANG(?title) = 'en')
}
ORDER BY DESC(?releaseDate)

Pattern 2: Population Queries

User: "What are the 10 most populous cities in France?"

SPARQL:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT ?city ?name ?population
WHERE {
  ?city dbo:country dbr:France ;
        a dbo:City ;
        rdfs:label ?name ;
        dbo:populationTotal ?population .
  FILTER(LANG(?name) = 'en')
}
ORDER BY DESC(?population)
LIMIT 10

Pattern 3: Person Information

User: "Tell me about Albert Einstein - when was he born and where?"

SPARQL:

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT ?birthDate ?birthPlace ?placeLabel
WHERE {
  dbr:Albert_Einstein dbo:birthDate ?birthDate ;
                      dbo:birthPlace ?birthPlace .
  ?birthPlace rdfs:label ?placeLabel .
  FILTER(LANG(?placeLabel) = 'en')
}

HTML Template Generation

When generating HTML results:

Required Elements

1. Title: Question or query description
2. Statistics: Number of results, query execution time
3. Table: Results with hyperlinked DBpedia URIs
4. SPARQL Query Display: Show the executed query
5. Footer: Link to DBpedia, data source attribution

Styling Guidelines

• Use gradient backgrounds
• Responsive design (mobile-friendly)
• Hover effects on table rows
• Hyperlink all DBpedia resources
• Color-code different data types
• Include icons for visual appeal

HTML Template Structure

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>[Query Description] - DBpedia</title>
    <style>
        /* Modern, responsive styling */
        /* Gradient backgrounds */
        /* Hover effects */
        /* Mobile-first design */
    </style>
</head>
<body>
    <div class="container">
        <h1>[Question/Title]</h1>
        <div class="stats">[Results count]</div>
        <table>[Results]</table>
        <div class="sparql-query">[Query code]</div>
        <div class="footer">[Attribution]</div>
    </div>
</body>
</html>

Error Handling

No Results

If query returns 0 results:

• Inform user clearly
• Suggest alternative phrasings
• Check for typos in entity names

Query Errors

If SPARQL syntax error:

• Display error message
• Show attempted query
• Offer to reformulate

Timeout

If query times out:

• Add LIMIT clause
• Simplify query complexity
• Suggest narrowing criteria

Output Preferences

Always ask the user:

"Would you like the results as:
1. JSON (raw data)
2. Markdown table (terminal display)
3. HTML page (interactive visualization)"

Best Practices

1. Always use DISTINCT: Avoid duplicate results
2. Filter by language: Use FILTER(LANG(?label) = 'en')
3. Add LIMIT: Default to LIMIT 100 unless specified
4. Use OPTIONAL: For properties that may not exist
5. Order results: Make results meaningful with ORDER BY
6. Hyperlink in HTML: All DBpedia URIs should be clickable

Example Session

User: "List books written by J.K. Rowling with publication dates"

Assistant:
"I'll query DBpedia for books authored by J.K. Rowling.

Executing SPARQL query against DBpedia endpoint..."

[Constructs and executes query]

"Found 15 books! Would you like the results as:

1. JSON
2. Markdown table
3. HTML page"

User: "HTML page"

Assistant:
[Generates beautiful HTML page with results]

"✓ HTML page generated and saved to: ./jkrowlingbooks.html
✓ 15 books found with publication dates"

Scope

This skill handles:

• Queries about entities in DBpedia
• Structured data extraction
• Result formatting and visualization

This skill does NOT handle:

• Text search (use DBpedia Lookup API instead)
• Data modification (read-only queries)
• Real-time data (DBpedia updates periodically)

Version: 1.0.0
Endpoint: https://dbpedia.org/sparql
Data Source: DBpedia (Wikipedia structured data)