nexus-mcp
Allows LangGraph agents to perform hybrid document search and schema extraction across tenant-isolated knowledge bases.
Exports OpenTelemetry traces and metrics for monitoring tool invocations and system performance.
Exports tool execution metrics such as invocation counts, p95/p99 latency, and token expenditure to Prometheus.
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@nexus-mcpsearch our internal knowledge base for data retention policies"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
Nexus-MCP ā”
Overview
Nexus-MCP is an enterprise-grade Model Context Protocol (MCP) gateway and security router that gives AI agents (Claude Desktop, Cursor, LangGraph) secure, observable access to internal corporate knowledge.
Raw MCP implementations lack multi-tenancy, dynamic RBAC, tool injection protection, and audit logs. Nexus-MCP bridges this gap by acting as a zero-trust security router and document intelligence server.
Related MCP server: evav-gateway
š The Enterprise Golden Path
MCP Client āā> Authentication & Tenant Context āā> RBAC Scope Check
ā
ā¼
Prometheus & OTel āāā Response āāā Schema Extraction āāā Hybrid RAG (Vector+BM25)Key Features
ā” Official Anthropic MCP SDK Integration: Built natively on Anthropic's
mcpspecification supporting STDIO & SSE JSON-RPC transports.š Multi-Tenant & ACL Isolation: Strictly isolates document search and schema extraction per
tenant_idand useracl_groups.š”ļø Security Router & Prompt Injection Sanitizer: Prevents prompt/tool injection attacks (
DROP TABLE,IGNORE INSTRUCTIONS).š Hybrid Vector + BM25 Retrieval: Reciprocal Rank Fusion (RRF) combining dense vector similarity and BM25 term frequency.
š Prometheus & OpenTelemetry Observability: Tracks tool execution counts, p95/p99 latency, and token expenditure.
Quick Start
Installation
pip install nexus-mcpOr install locally for development:
git clone https://github.com/JasleenSingh/nexus-mcp.git
cd nexus-mcp
pip install -e .Code Example: Golden Path Demo
Run the included commercial contract intelligence demo:
python examples/contract_intelligence_demo.pyOutput:
š Starting Nexus-MCP Enterprise Golden Path Demo...
ā
Ingested document into 4 hierarchical chunks for tenant 'tenant-acme-corp'.
š Executing Tool [doc_hybrid_search]...
Found 1 matching chunks with Hybrid Vector + BM25 search.
š Executing Tool [doc_extract_schema]...
Extracted Agreement Schema (3 fields):
⢠payment_terms: Net 30 days (confidence: 0.92)
⢠total_contract_value: $3,500,000.00 (confidence: 0.88)
⢠governing_law: State of Delaware (confidence: 0.90)
š Executing Tool [system_health_telemetry]...
System Health: healthy
⨠Nexus-MCP Golden Path Execution Completed Successfully!Running Server & CLI
# Start Nexus-MCP server over STDIO transport
nexus-mcp serve --transport stdioRunning Tests & Benchmarks
# Run complete unit, integration, and security test suite
pytest tests/
# Run retrieval accuracy benchmarks (Recall@K & MRR)
pytest tests/integration/test_retrieval_benchmarks.py -vProject Structure
nexus-mcp/
āāā src/nexus_mcp/
ā āāā models/ # Pydantic v2 domain schemas (TenantContext, DocumentChunk, SearchQuery)
ā āāā document_processor/ # Hierarchical chunker, schema extractor, and Hybrid RAG retriever
ā āāā security/ # RBAC scope validator and input injection sanitizer
ā āāā observability/ # Prometheus metrics and OpenTelemetry trace span exporters
ā āāā mcp_server/ # Official Anthropic MCP Server & tool registrations
ā āāā cli/ # Rich CLI interface (nexus-mcp serve)
āāā tests/
ā āāā unit/ # Unit tests (chunker, retriever, schemas, observability)
ā āāā integration/ # MCP JSON-RPC protocol & retrieval benchmarks
ā āāā security/ # Adversarial security tests (cross-tenant & prompt injection)
āāā examples/ # Contract intelligence demo & sample commercial agreements
āāā docs/ # System architecture & tool specs
āāā pyproject.toml
āāā README.mdLicense
Distributed under the MIT License.
This server cannot be deployed
Maintenance
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