Search the GraphRAG knowledge base with THREE distinct modes:

CRITICAL: For ticker symbols (ASTS, RKLB, NBIS) or acronyms, ALWAYS use 'keyword_lookup' FIRST. Semantic search (entity_connections/thematic_overview) can MISS exact ticker matches.

Workflow:

1. Ticker/Acronym Query → Use 'keyword_lookup' to find raw mentions

2. If found → Extract entity names from results

3. Then use 'entity_connections' or 'thematic_overview' with full entity names for deeper analysis

Mode Selection Guide:

• 'keyword_lookup': Direct BM25 retrieval for EXACT terms (tickers, acronyms, specific names) → Returns: Raw text chunks containing the literal search term → Use for: ASTS, NYSE:RKLB, "Direct-to-Cell", specific product names

• 'entity_connections': Find entities and their knowledge graph relationships → Returns: Entities + relationships + supporting chunks → Use for: Company relationships, competitive landscape, partnerships → Example: After finding 'AST SpaceMobile' via keyword_lookup, search 'AST SpaceMobile competitors partners'

• 'thematic_overview': High-level patterns and trends across corpus → Returns: Broad thematic context → Use for: Industry trends, macro narratives, sector analysis → Example: 'satellite telecommunications market trends'

Traverse the knowledge graph starting from a specific entity. Returns the entity, its direct connections (other entities), and the relationships between them. Use this to build reasoning chains or verify facts about a known entity.

Get statistics about the indexed knowledge base. Returns counts of documents, chunks, entities, and relationships. Use for corpus health checks or to understand the scale of available data.