AI Engineer, Graduate Researcher
Boston University, Questrom Computational LabMay 2026 to present · Boston, MA
- 14
- tools on one LangGraph agent
- BM25 + vector
- hybrid retrieval, Cohere reranked
- LLM-as-a-Judge
- hallucination and retrieval scoring
- Azure OpenAI GPT-4o
- Azure AI Search
- LangGraph
- FastAPI
- React
- Cosmos DB Gremlin
- Cohere
He architected a document intelligence assistant for an enterprise consulting client, on Azure, owned from ingestion through deployment.
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The constraint: consultants needed answers grounded in a large private document corpus, where a wrong answer delivered confidently is worse than no answer.
What he built. A LangGraph agent exposing 14 tools covering document question answering, cross-document comparison, and template-driven generation. Hybrid retrieval fusing BM25 keyword search with vector search, plus LLM-based query rewriting and Cohere re-ranking. LLM-as-a-Judge evaluations measuring hallucination rate and retrieval quality. PII and entity redaction guardrails applied across ingested documents. Header-aware chunking, Markdown-header splitting plus recursive splitting, with SHA-256 deduplication and Azure Blob Storage metadata. Streaming FastAPI endpoints over Server-Sent Events with a React single-page app. A Cosmos DB Gremlin knowledge graph linking clients, projects, and technologies.
The trade-off worth asking about: hybrid retrieval costs more per query than dense-only. Dense embeddings compress meaning and lose surface form, so they miss exact terms, and in a consulting corpus the exact terms are client names, project codes, and document titles. The cost was worth it.