Graph Exploration

Graph Exploration

Use this skill to explore the Wikidata graph around seed entities and candidate properties. This skill runs small, bounded SPARQL queries to progressively build evidence for the graph pattern required by the final query.

Files

• scripts/graph_explorer.py: standalone script for exploring the Wikidata graph

When To Use This Skill

Use this skill when:

• You need to verify that a property connects two entities in the expected direction
• You need to discover which properties an entity has
• You need to check whether a direct property (wdt:) or statement node (p:/ps:/pq:) is needed
• You need to find the correct graph path between two entities
• You need to inspect qualifiers on a statement
• You need to verify instance_of / subclass_of patterns for type filtering

Requirements

Install skill dependencies from the workspace root with uv sync.

The script uses the requests library to send SPARQL queries to the Wikidata Query Service. No API keys required.

Environment Variables

None required. The Wikidata SPARQL endpoint is publicly accessible.

Optional:

• WIKIDATA_SPARQL_ENDPOINT: Override the SPARQL endpoint URL. Default: https://wikikgqa.skynet.coypu.org/wikidata.
• WIKIDATA_USER_AGENT: Custom User-Agent string. Default: "AgenticText2SPARQL/1.0".

Safety Rules

• All queries are read-only (SELECT/ASK only).
• All exploration queries MUST include a LIMIT clause (max 50 results) to avoid overloading the endpoint.
• Never run unbounded subclass traversals without a LIMIT.
• Space requests at least 1 second apart to respect Wikidata rate limits.
• If a query times out, simplify it rather than retrying the same query.

Exploration Modes

1. Outgoing Properties (outgoing)

List all properties and sample values going out from an entity:

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity "Q937" \
  --mode outgoing \
  --limit 20

Returns: properties (PIDs + labels) used as predicates where the entity is the subject, with sample object values.

2. Incoming Properties (incoming)

List entities that point to the given entity via a specific property (or all properties):

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity "Q937" \
  --mode incoming \
  --limit 20

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity "Q937" \
  --mode incoming \
  --property "P19" \
  --limit 10

Returns: entities that have the given entity as an object value (reverse relations).

3. Check Property (check-property)

Verify whether a specific property connects an entity to anything:

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity "Q937" \
  --mode check-property \
  --property "P19"

Returns: whether the property exists on the entity, its value(s), and direction confirmation.

4. Type Hierarchy (types)

Inspect instance_of and subclass_of chains:

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity "Q937" \
  --mode types

Returns: instance_of values, and for classes, their subclass_of chain.

5. Statement Details (statement)

Inspect the full statement node including qualifiers:

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity "Q937" \
  --mode statement \
  --property "P69"

Returns: statement nodes with main values and all qualifiers (start time, end time, etc.).

6. Path Discovery (path)

Find how two entities are connected:

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity "Q937" \
  --mode path \
  --target "Q243"

Returns: properties that connect the two entities directly or through one intermediate node.

7. Custom Query (custom)

Run an arbitrary bounded SPARQL query for exploration:

uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --mode custom \
  --sparql "SELECT ?p ?pLabel ?o ?oLabel WHERE { wd:Q937 ?p ?o . OPTIONAL { ?p rdfs:label ?pLabel FILTER(LANG(?pLabel) = 'en') } OPTIONAL { ?o rdfs:label ?oLabel FILTER(LANG(?oLabel) = 'en') } } LIMIT 10"

Script Usage

Arguments

Required:

• --mode / -m: Exploration mode (outgoing, incoming, check-property, types, statement, path, custom)

Mode-specific:

• --entity / -e: Wikidata entity ID (e.g., Q937) — required for all modes except custom
• --property / -p: Wikidata property ID (e.g., P19) — required for check-property and statement modes
• --target: Target entity ID — required for path mode
• --sparql: SPARQL query string — required for custom mode

Optional:

• --limit / -l: Maximum results (default: 20, max: 50)
• --output-file: Write result JSON to a file instead of stdout

Return Shape

Outgoing Properties Result

{
  "success": true,
  "entity": "Q937",
  "entity_label": "Albert Einstein",
  "mode": "outgoing",
  "result_count": 20,
  "results": [
    {
      "property": "P19",
      "property_label": "place of birth",
      "value": "Q3012",
      "value_label": "Ulm",
      "value_type": "wikibase-item"
    },
    {
      "property": "P569",
      "property_label": "date of birth",
      "value": "1879-03-14T00:00:00Z",
      "value_label": "14 March 1879",
      "value_type": "time"
    }
  ],
  "error": null
}

Check Property Result

{
  "success": true,
  "entity": "Q937",
  "entity_label": "Albert Einstein",
  "mode": "check-property",
  "property": "P19",
  "property_label": "place of birth",
  "exists": true,
  "direction": "outgoing",
  "values": [
    {
      "value": "Q3012",
      "value_label": "Ulm"
    }
  ],
  "error": null
}

Statement Details Result

{
  "success": true,
  "entity": "Q937",
  "entity_label": "Albert Einstein",
  "mode": "statement",
  "property": "P69",
  "property_label": "educated at",
  "result_count": 3,
  "results": [
    {
      "statement_id": "Q937$some-guid",
      "main_value": "Q11942",
      "main_value_label": "ETH Zurich",
      "qualifiers": [
        {
          "property": "P580",
          "property_label": "start time",
          "value": "1896-01-01T00:00:00Z"
        },
        {
          "property": "P582",
          "property_label": "end time",
          "value": "1900-01-01T00:00:00Z"
        },
        {
          "property": "P512",
          "property_label": "academic degree",
          "value": "Q752297",
          "value_label": "diploma"
        }
      ]
    }
  ],
  "error": null
}

Wikidata Prefixes Reference

When to use wdt: vs p:/ps:/pq:

• Use wdt: (direct) for simple facts: wd:Q937 wdt:P19 ?birthplace
• Use p:/ps:/pq: when you need qualifiers:

  wd:Q937 p:P69 ?stmt .
  ?stmt ps:P69 ?school ;
        pq:P580 ?startDate .
  

Integration with text2sparql Pipeline

Recommended Workflow

After wikidata-search has identified candidate IDs:

1. Verify entity types:

   uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
     --entity "Q937" --mode types
   

2. Check property existence and direction:

   uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
     --entity "Q937" --mode check-property --property "P19"
   

3. Explore outgoing if property is unknown:

   uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
     --entity "Q937" --mode outgoing --limit 30
   

4. Inspect qualifiers if needed:

   uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
     --entity "Q937" --mode statement --property "P69"
   

5. Find path between entities:

   uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
     --entity "Q937" --mode path --target "Q243"
   

Decision Tree

Is the relationship between entities clear and well-known?
├── YES → Skip exploration, go directly to SPARQL generation
└── NO → Explore
         ├── Do you know the property?
         │   ├── YES → Use check-property mode
         │   └── NO → Use outgoing mode on subject entity
         ├── Is the direction (subject→object) confirmed?
         │   ├── YES → Proceed to generation
         │   └── NO → Try BOTH directions (outgoing + incoming) to see which has data
         ├── Are qualifiers needed?
         │   ├── YES → Use statement mode to see qualifiers (P580, P582, P1545, etc.)
         │   └── NO → Use wdt: in generation
         ├── Is the property a quantity (distance, mass, area, speed)?
         │   └── YES → Check if psn: (normalized value) is available via statement mode
         └── Does the question ask about "current" state or "all-time" history?
             ├── CURRENT → Need MINUS { pq:P582 ?end } to exclude ended statements
             └── ALL-TIME → Need p:/ps: to access all historical values, not just wdt: truthy

Key Exploration Principles

1. Always verify property direction: When a property could go either way (e.g., P674 "characters" vs P1441 "present in work of fiction"), check BOTH the subject's outgoing properties AND the object's outgoing properties. Use the direction that actually returns data.

   Important: Many relationships in Wikidata are modeled from both sides. For example, "character in a film" can be expressed as:

   • From the film: ?film wdt:P674 ?character (film has character)
   • From the character: ?character wdt:P1441 ?film (character present in work)

   Always try both directions and use whichever returns results from the endpoint. If both return results, use the one that gives the most complete answer (more results).

2. Note the property datatype: The value type matters for SPARQL generation:

   • wikibase-item → return the QID, not a label
   • quantity → use psn: for normalized SI values
   • time → may need date arithmetic or FILTER
   • string → direct literal comparison

3. Check for qualifier structure: If the question involves ordering ("most recent", "2nd", "current"), use statement mode to see what qualifiers exist (P580 start time, P582 end time, P1545 series ordinal, P585 point in time).

4. Verify membership/containment relationships: When the question mentions a group/category (e.g., "Latin American countries"), check which specific property links entities to that group. Use incoming mode on the group entity to see exactly which items are linked and via which property. Do not approximate with broader relationships (e.g., do not use "continent = South America" when the question says "Latin America").

Handling Pre-resolved Mentions

When entity/property mentions are provided as input, use these additional exploration strategies:

Discovering Intermediate Classes

When mentions provide two concepts that should be combined (e.g., "video games" Q7889 + "NP-complete" Q180074), check if Wikidata has a combined class:

# Check if there's an intermediate class combining both concepts
uv run python .agents/skills/graph-exploration/scripts/graph_explorer.py \
  --entity Q7889 --mode subclasses --limit 50

Look for subclasses that incorporate the second concept (e.g., Q21055677 "NP-complete problem in video games"). Using such intermediate classes with wdt:P31 wd:Q_combined is often more complete than intersecting two separate constraints.

Verifying Concept vs. Class Entities

When a mention maps to a broad concept or movement (e.g., "open source" → Q39162), verify whether it's the right entity for a P31/P279 query:

1. Check what wdt:P31 wd:Q_mentioned actually returns — if zero results or irrelevant results, the entity may be a concept/movement rather than a classifying type
2. Search for a more specific class: e.g., "open-source software" (Q1130645) instead of "open source" (Q39162)
3. Check the entity's description and P31 to understand its nature

Discovering Missing Linking Properties

When mentions provide entities but no linking property (e.g., "flags" Q186516 and "pink" Q429220 but no property connecting them):

1. Explore outgoing properties of the subject entity to find which property connects to the object
2. Try common linking properties: P462 (color), P180 (depicts), P527 (has parts), P921 (main subject)
3. Run a diagnostic query: SELECT ?p WHERE { wd:Q_subject ?p wd:Q_object } LIMIT 10

Troubleshooting

• Timeout on outgoing properties: Some entities have hundreds of properties. Use --limit and consider filtering by property type.
• Property exists but shows no values: The property may use deprecated/non-truthy ranks. Try statement mode.
• Path discovery returns nothing: The entities may be connected through more than one intermediate node, or through a different property than expected.
• Unexpected value types: Wikidata stores some values as quantity nodes, time nodes, or coordinate nodes rather than simple literals.
• Too many incoming results: Add a type constraint or use check-property instead of full incoming scan.