Architectural Case Study

Enterprise HRMS AI Assistant with Model Context Protocol (MCP)

Enterprise HRMS assistant built on Claude and MCP with strict RBAC isolation

Technical Lead & Principal AI Architect
Led 5-person engineering team (2 BE, 3 AI engineers) with direct hands-on implementation
2025
System Specification // ENTERPRISE-HRMS-AI-ASSISTANT-MCP
PRODUCTION ARCHITECTURE
Architectural Mandate & Scope

Architected and built an enterprise AI assistant embedded into a Human Resource Management System using the Model Context Protocol (MCP). Implemented multi-layered role-based access control (RBAC), dynamic tool schema filtering based on user JWTs, PostgreSQL Row-Level Security, and immutable audit logging across payroll, leave, and hiring workflows.

Quantified Telemetry & Performance Baselines
permission Enforcement
100% role-based MCP tool schema boundary isolation
audit Coverage
Comprehensive logging of all tool calls and payloads
tool Ecosystem
6 production MCP servers (Leave, Payroll, Hiring, Policy)
security Model
Multi-layered defense: JWT filtering, tool validation & DB RLS
Engineered Technology Stack
Anthropic ClaudeModel Context Protocol (MCP)PythonLangGraphPostgreSQLRow-Level Security (RLS)RedisDockerAWS
Topology:AI & Search Systems
Deployment:Enterprise Human Resource Management Platform
Cycle:6 months delivery
Leadership & Engineering Organization

Engineering team structure and leadership.

How the engineering organization was structured, staffed across disciplines, and directed through delivery.

Leadership Mandate
Technical Lead & Principal AI Architect
5-Person Focused AI & Backend Engineering Team Guided by Yogesh
Cross-Functional Discipline Matrix
3 Specialized Functional Pods
Principal Architecture & OrchestrationYogesh

Overall technical leadership, custom Python orchestration, and MCP security boundary design

AI & MCP Tool Engineering3 AI Engineers

Claude 3.5 prompt engineering, MCP tool servers (Leave, Directory, Reviews, Hiring), evaluation suites

Backend & Data Isolation2 Backend Engineers

PostgreSQL Row-Level Security, enterprise SSO JWT integration, and SQL audit logging

Direct Architectural Contributions & Critical Paths
Personally Engineered & Directed
01

Provided hands-on technical leadership over 5 engineers while personally writing core backend orchestrators and MCP server code

02

Architected the Model Context Protocol (MCP) server cluster spanning Leave, Payroll, Org Directory, Reviews, Policy, and Hiring

03

Engineered the security architecture that dynamically filters tool schemas based on user JWT claims before sending context to Claude

04

Implemented PostgreSQL Row-Level Security (RLS) guaranteeing cryptographic data isolation across organizational tiers

05

Built a comprehensive database audit pipeline logging 100% of LLM tool calls, arguments, user identities, and execution statuses

System Benchmarks & Outcomes

Measured operational outcomes.

Concrete reliability benchmarks and performance metrics delivered to production.

Metric 01
100% role-based MCP tool schema boundary isolation

Permission Enforcement

Metric 02
Comprehensive logging of all tool calls and payloads

Audit Coverage

Metric 03
6 production MCP servers (Leave, Payroll, Hiring, Policy)

Tool Ecosystem

Metric 04
Multi-layered defense: JWT filtering, tool validation & DB RLS

Security Model

Technical Execution

Architectural decisions & implementation.

Target Architecture & Implementation

How the system was designed, structured, and deployed

Designed a multi-tier defense architecture using Model Context Protocol (MCP). When an employee authenticates, their verified JWT role dynamically filters which MCP tool schemas are presented to Claude—ensuring the model cannot even attempt to call unprivileged functions. At execution time, MCP servers validate user identity and permissions, while PostgreSQL Row-Level Security (RLS) restricts database queries strictly to the requester's authorized records. Every tool invocation, parameter, and timestamp is permanently recorded to an immutable audit table.

System Component & Infrastructure Ledger

Detailed breakdown of runtime dependencies, protocols, and architectural roles

8 Core Subsystems
01
Anthropic Claude 3.5 Sonnet and Haiku via API

Reasoning and tool orchestration

02
Model Context Protocol (MCP) tool servers

Decoupled, auditable business logic

03
Custom Python orchestrator with LangGraph

Deterministic state and fallback handling

04
PostgreSQL

Row-Level Security (RLS) enforcing tenant and employee record isolation

05
Redis

Session caching, token budgeting, and conversational context storage

06
Enterprise JWT authentication integration

Corporate Single Sign-On (SSO)

07
Docker containerized MCP micro-services

Individual network isolation

08
Immutable SQL audit pipeline

Regulatory compliance and access tracking

"The MCP architecture gave our security review team the confidence to approve an AI assistant in HRMS. The permission boundaries are mathematically enforced, not just prompted."
Vo
VP of Enterprise Security

Enterprise Human Resource Management Platform