feat(llc/kb): Sub-company KB inheritance — parent KB read-through with weight decay #8241

Parent

Phase 5 (#8209) · Umbrella (#8204)

Depends On

#8235 — KB collection lifecycle. #8236 — Context builder (inheritance applied here).

Context

Sub-companies automatically inherit parent company policies and guidelines via read-through. A subsidiary can use parent LLC standards without duplicating them, while still prioritizing its own company context.

Acceptance Criteria

• KbInheritanceResolver in llc/kb/inheritance.py:
  • get_query_collections(company_id) -> list[tuple[str, float]]:
    • Walks parent_org_id chain from company to root
    • Returns list of (collection_name, weight) tuples
    • Weight decay: own company = 1.0, parent = 0.6, grandparent = 0.36 (configurable multiplier, default 0.6 per level)
  • search_with_inheritance(company_id, query, top_k=10) -> list[KbResult]:
    • Issues parallel RAG queries across all collections in the chain
    • Merges and re-ranks results by score * weight
    • Returns top_k results with source_company_id annotation
• Weight multiplier configurable per company: llc_companies.kb_inheritance_weight FLOAT DEFAULT 0.6
• KbInheritanceResolver integrated into HeartbeatContextBuilder.build() — replaces direct company collection query with inherited query
• Sub-company agents CANNOT write to parent company collections (enforced in collection write path)
• GET /api/llc/companies/{id}/kb/ancestry-collections — returns the resolved collection chain for inspection
• python -m pytest autobot-backend/llc/ -k kb_inheritance passes