Reliability Infrastructure for Legal AI Agents
Why Lexstack
Stop stitching PDF parsing, vector search, chat history, tool orchestration, and evaluation from scratch. LexStack gives you production-ready components designed specifically for legal workflows.
Citation-aware by design
Answers include structured references, page numbers, and bounding boxes. Grounded outputs you can highlight and verify.
Built for real legal complexity
Hybrid retrieval, linked-document awareness, and multi-step reasoning through LangGraph agents.
Open-source core
Self-host LexReviewer. Extend it. Audit it. Scale with hosted APIs and usage-based infrastructure when needed.
Capabilities
Everything you need to scale AI.
Grounded Legal RAG with Highlightable Citations
Turn complex legal PDFs into a structured, citation-first chat system. LexReviewer ingests documents, performs hybrid retrieval, and streams grounded answers with reference positions and bounding boxes suitable for UI highlighting. Built for real legal workflows, not generic PDF chat.
Predictable Legal Tools for Agent Workflows
Law MCP standardizes legal capabilities as structured tools with consistent schemas. Instead of brittle scraping or inconsistent APIs, agents call well-defined legal functions designed for grounded outputs. It extends beyond private documents into structured legal sources.
Regression Protection for Legal AI Systems
MicroEvals adds fast, repeatable behavioral tests that run in CI. Catch formatting drift, citation failures, tool-call errors, and guardrail regressions before production. Legal AI cannot silently degrade. MicroEvals enforces quality gates.
Features
LexStack provides the core capabilities teams need to build, deploy, and operate AI systems reliably at production scale across environments.
Hybrid Retrieval Engine
Combine vector search and keyword retrieval to handle both semantic queries and exact clause lookups with document-level precision.
Streaming Legal Chat
Stream grounded responses in real time with structured references and highlight-ready citation metadata.
Persistent Conversation State
Maintain multi-turn, document-scoped chat history with reliable context handling and session isolation.
Linked Document Awareness
Automatically resolve and query referenced amendments, schedules, and related agreements for full contract context.
Observability
Trace retrieval, reasoning, and responses with built-in instrumentation for debugging and production monitoring.
Production-Ready API
Comprehensive backend endpoints for ingestion, chat, history, and lifecycle management without frontend lock-in.
Workflow
End-to-end production flow.
Giga streamlines the entire AI lifecycle so teams can move from experimentation to deployment without fragmentation or operational overhead.
1. Ingest
Turn legal documents into AI-ready context
Upload PDFs and index them into a structured retrieval system.
2. Generate
Produce grounded legal outputs in seconds
Query indexed documents through a hybrid retrieval + agent pipeline.
3. Refine
Iterate with control and confidence
Improve system behavior before it reaches production.
4. Deploy
Move from prototype to production safely from output to real-world impact
Ship with observability, cost control, and infrastructure flexibility.
Integration
Integrates with the
tools you already use.
LexStack fits into your existing AI and infrastructure stack. Plug it into your agents, CI pipelines, databases, and deployment environment without rebuilding your system architecture.
FAQ
What is LexStack?
Is LexStack open source?
Who is this for?
What is Law MCP exactly?
What’s included in “US Law”?
What is MicroEvals? How is it different from full benchmarks?
Can I run MicroEvals in GitHub Actions?
Does this work with LangGraph / LangChain / custom agents?
Can we self-host?
How do you handle privacy and data retention?
How do we get started?
What’s the pricing model?