materials-knowledge-graph

name	materials-knowledge-graph
description	Use for materials science knowledge graph tasks — extracting entities, building graph, querying by material/mode/property, finding data gaps, or any task involving the kg_engine/ module. Triggers on materials science queries, alloy/property extraction, graph construction, gap analysis, or hybrid search.

Materials Knowledge Graph Skill

Enables building and querying a knowledge graph for materials science from document corpora.

Architecture Overview

materials-kg/
  kg_engine/
    domain/          # Typed entities, relations, observations, traces, query DTOs
    repositories/    # Persistence protocol + Neo4j runtime, test memory
    services/        # Ingestion/query/hypothesis API
    agents/          # Deep Agents orchestration over read-only graph tools
    api/             # Application-facing HTTP/UI entrypoints
    ingestion/       # File parsing and payload adapters
    llm_core/        # LLM provider, extraction, answer generation
    config/          # Settings, env-driven configuration
    scripts/         # CLI ingestion and API startup scripts
    tests/           # Test suite

Entity Types (8)

Type	Description	Example
MATERIAL	Metals, alloys, ceramics, polymers, composites	Ti-6Al-4V, CuCrZr, 316L, IN718
EXPERIMENT	Test name, experiment description	tensile_test, fatigue_test
PROPERTY	Mechanical, thermal, electrical, physical	tensile_strength, hardness, conductivity
MODE	Processing mode, test conditions	annealing, HIP, LPBF, aging
EQUIPMENT	Devices, machines, instruments	SEM, XRD, tensile_machine
TEAM	Research groups, labs, universities	MIT_Materials_Lab
DOCUMENT	Publication, report, document	doi:10.1000/xyz
TAG	Findings, results, observations	Strength increased by 15%

Relation Types (9)

Type	Description
EVALUATES_MATERIAL	Experiment evaluates a material
USES_MODE	Material/experiment uses a processing mode
MEASURES_PROPERTY	Experiment measures a property
USES_EQUIPMENT	Experiment uses specific equipment
PERFORMED_BY	Experiment conducted by a team
DOCUMENTED_IN	Experiment described in a document
TAGGED_WITH	Entity tagged with a finding/conclusion
REFERENCES	Entity references another entity
RELATED_TO	Generic relation between entities

Module Responsibilities

Module	File	Purpose
domain	models.py	Pydantic models — entities, evidence, relations, observations, DTOs
domain	resolution.py	Canonical name resolution via alias normalization
repositories	protocols.py	Persistence contract used by the service layer
repositories	neo4j.py	Primary runtime backend, Neo4j nodes and relationships
repositories	memory.py	In-memory storage for unit tests only
repositories	factory.py	Environment-driven repository bootstrap
services	materials_kg.py	Public graph-first ingestion, query, and deterministic hypothesis API
services	hypothesis_adjustments.py	Expert adjustment schema and score recalculation
services	session.py	In-memory conversation session store with TTL
agents	hypothesis_factory.py	Deep Agents orchestration for hypothesis generation
agents	hypothesis_tools.py	Read-only graph tools exposed to the agent
agents	extraction_agent.py	Deep Agents orchestration for document entity extraction
api	materials_core.py	FastAPI app with upload, query, hypothesis, and graph endpoints
ingestion	adapters.py	Normalize raw source-family payloads into domain inputs
llm_core	provider.py	OpenAI-compatible LLM provider with streaming and retry
llm_core	extraction.py	LLM-powered entity extraction and answer generation
llm_core	token_budget.py	Token budget management for context window fitting

Query Examples

Ingest reference data

from kg_engine.services.materials_kg import MaterialsKGService
from kg_engine.domain.models import ReferenceDataBatch, CanonicalEntityInput, EntityKind

service = MaterialsKGService(repo)
service.ingest_reference_data(
    ReferenceDataBatch(
        entities=[CanonicalEntityInput(kind=EntityKind.MATERIAL, name="Ti-6Al-4V")]
    )
)

Resolve entity

entity = repo.resolve_entity(EntityKind.MATERIAL, "Ti-6Al-4V")
# Returns: CanonicalEntity with canonical_name, aliases, kind

Command Reference

# Venv
.venv\Scripts\Activate.ps1                   # Windows PowerShell
source .venv/bin/activate                     # Linux/WSL

# Install
pip install -e ".[dev]"

# Test
python -m pytest kg_engine/tests/ -v

# Lint
ruff check kg_engine/
ruff check --fix --unsafe-fixes kg_engine/

# Ingest data
python kg_engine/scripts/ingest_materials_kg.py --input path/to/data --ensure-schema

Code References

• kg_engine/domain/models.py — Entity/relation type definitions
• kg_engine/repositories/neo4j.py — Graph storage with Neo4j
• kg_engine/llm_core/extraction.py — Entity extraction
• kg_engine/services/materials_kg.py — Query and ingestion API
• kg_engine/agents/hypothesis_tools.py — LangChain tools

Agent Files Reference

All agent-facing files in this project must stay consistent:

File	Purpose
AGENTS.md	Source of truth — full conventions, dev commands, structure
.agents/skills/materials-knowledge-graph/SKILL.md (this file)	Domain skill — architecture, entity/relation types, query examples
.cursor/rules/materials-kg-agent.mdc	Coding rules, domain overview, key patterns
.cursor/rules/terminal.mdc	Terminal setup, venv, common commands
.cursor/rules/commit.mdc	Commit message format and guidelines