MCP LlamaIndex SQLite Bridge

A comprehensive demonstration of Model Context Protocol (MCP) with SQLite integration and LlamaIndex client, featuring both a simple demo and a full-featured HR Management System.

Overview

This project showcases how to build and use MCP servers that expose database operations as tools, connected via LlamaIndex-based clients with Ollama LLM support. It includes:

1. Simple Demo - Basic SQLite server with simple people table

2. HR Management System - Advanced natural language HR system with employee management, leave tracking, compensation, and analytics

Components

Simple Demo:

• server.py: Basic MCP server with SQL tools for a simple people database

• client.py: LlamaIndex client for natural language database interactions

HR Management System:

• hr_server.py: Advanced MCP server with comprehensive HR tools

• hr_client.py: Sophisticated client with context-aware natural language processing

• HR_USAGE_GUIDE.md: Detailed documentation with examples

Related MCP server: sqlite-explorer-fastmcp-mcp-server

Features

Core Features

• MCP server architecture with SQLite integration

• Natural language interface using LlamaIndex and Ollama

• Async support for both server and client

• Tool-based approach for database operations

HR Management System Features

• Employee Management: Add, update, search, and manage employee records

• Leave Management: Request, approve, and track employee leave balances

• Compensation: Salary updates, compensation reports, and payroll analytics

• Organization Structure: Org charts, department management, and transfers

• Analytics: HR dashboards, turnover analysis, and diversity metrics

• Performance Reviews: Create and track performance evaluations

• Audit Trail: Complete logging of all HR actions for compliance

Prerequisites

• Python 3.8+

• Ollama installed and running

• llama3.2 model (or another model that supports tool calling)

⚠️ Critical Requirements

Email is REQUIRED When Adding Employees

The HR system requires an email address when adding new employees. Commands without email will fail.

❌ WRONG: Add John Doe to Engineering as Developer
✅ CORRECT: Add John Doe (john.doe@company.com) to Engineering as Developer

Without email, you'll see: ❌ Tool failed: Missing required field: email

Installation

1. Clone this repository:

git clone https://github.com/ELISHA1994/mcp-llama-sqlite-bridge.git
cd mcp-llama-sqlite-bridge

2. Create a virtual environment:

python -m venv .venv
source .venv/bin/activate  # On Windows: .venv\Scripts\activate

3. Install dependencies:

pip install -r requirements.txt

4. Pull the required Ollama model:

ollama pull llama3.2

Usage

Option 1: Simple Demo

Starting the Simple Server

python server.py --server_type=sse

Running the Simple Client

python client.py

Option 2: HR Management System

Starting the HR Server

python hr_server.py --server_type=sse

Running the HR Client

python hr_client.py

The client will:

1. Connect to the MCP server

2. Display available tools

3. Start an interactive session where you can use natural language to interact with the database

Example Interactions

Simple Demo:

Enter your message: Add a person named John Doe who is 30 years old and works as an Engineer
Agent: Data has been successfully added to the database.

Enter your message: Show me all people in the database
Agent: Here are all the people in the database:
1. John Doe, 30 years old, Engineer

HR Management System:

⚠️ IMPORTANT: Email is REQUIRED when adding employees!

HR Assistant> Add Sarah Johnson (sarah.johnson@company.com) to Engineering as Senior Developer with $105,000 salary

🔧 Calling tool: add_employee
✅ Employee added successfully!
- Employee ID: EMP00001
- Name: Sarah Johnson

HR Assistant> 

🔧 Calling tool: check_employee_leave_balance
   Parameters: {
     "employee_name": "Sarah Johnson"
   }
✅ Tool result received
**Leave Balance for Sarah Johnson (2024)**
- Annual Leave: 21 days remaining
- Sick Leave: 10 days remaining

HR Assistant> Generate HR dashboard

🔧 Calling tool: generate_hr_dashboard
**HR Dashboard Summary**
- Total Employees: 45
- Active: 42
- Departments: Engineering (15), Sales (10), Marketing (8)...

Natural Language Examples

Employee Management

Adding Employees (Email Required!):

"Add Elisha Bello (elisha.bello@company.com) to Engineering as Senior Software Engineer with salary $420,000"
"Hire John Doe (john.doe@company.com) as Marketing Manager starting January 15, 2024"
"Onboard Alice Chen (alice.chen@company.com) to Sales as Account Executive, phone: 555-0123"

Searching & Listing:

"List all employees"
"Find all employees in Engineering department"
"Show me employees hired in the last 6 months"
"Who reports to John Smith?"
"Search for Senior Engineers"

Updates & Changes:

"Update John Doe's phone number to 555-9876"
"Transfer Sarah Johnson from Engineering to Product Management"
"Change Michael Brown's manager to Jennifer Wilson"
"Update Emily Davis's salary to $95,000 effective next month"  ← Uses name directly!

Leave Management

"Check Sarah Johnson's leave balance"  ← Uses employee name directly!
"Submit leave request for John Doe from Dec 20 to Dec 27"  ← Uses name!
"Approve leave request #45"
"Show all pending leave requests"
"How many vacation days does Michael Brown have left?"  ← Uses name!

Compensation & Benefits

"Generate compensation report for Engineering department"
"Show average salaries by position"
"Calculate total payroll for Q4 2024"
"List employees eligible for salary review"
"Compare department salary ranges"

Organization & Analytics

"Show org chart for Engineering department"
"Generate HR dashboard"
"Analyze turnover for last quarter"
"Show diversity metrics"
"List employees with upcoming work anniversaries"
"Who are the top performers this quarter?"

Performance Management

"Create performance review for Sarah Johnson"
"Show pending performance reviews"
"Update performance rating for John Doe to 'Exceeds Expectations'"
"List employees due for annual review"

For more examples, try the interactive help in the HR client by typing 'help'.

Database Schema

Simple Demo Schema

The demo.db contains a people table:

• id: INTEGER PRIMARY KEY AUTOINCREMENT

• name: TEXT NOT NULL

• age: INTEGER NOT NULL

• profession: TEXT NOT NULL

HR Management System Schema

The hr_management.db contains multiple interconnected tables:

• employees: Comprehensive employee records

• departments: Organizational units and hierarchy

• positions: Job titles and salary ranges

• salaries: Compensation history

• leave_types: Various leave categories

• leave_balances: Employee leave entitlements

• leave_requests: Leave request tracking

• performance_reviews: Performance evaluations

• training_programs: Training catalog

• employee_training: Training completion records

• audit_log: Compliance and audit trail

Available Tools

Simple Demo Tools

• add_data: Add records using SQL INSERT

• read_data: Query records using SQL SELECT

HR Management Tools

Simplified Tools (Use These - They Accept Employee Names!)

• add_employee: Add new employees (EMAIL REQUIRED!)

• check_employee_leave_balance: Check leave balance by employee NAME

• update_employee_salary: Update salary by employee NAME

• submit_leave_request: Submit leave request by employee NAME

• list_all_employees: Get all active employees

• find_employees_by_department: Search by department

Advanced Tools (Require Employee IDs)

• manage_employee: Add, update, terminate employees (requires employee_id)

• search_employees: Advanced employee search with filters

• get_org_chart: Generate organizational hierarchy

• request_leave: Submit leave requests (requires employee_id)

• approve_leave: Process leave approvals

• get_leave_balance: Check leave balances (requires employee_id)

• update_salary: Manage compensation (requires employee_id)

• generate_hr_dashboard: Comprehensive HR metrics

• analyze_turnover: Turnover analytics

• calculate_compensation_metrics: Salary statistics

• record_performance_review: Performance evaluations

• And many more...

Troubleshooting

ModuleNotFoundError

If you encounter module import errors, ensure all dependencies are installed:

pip install -r requirements.txt

Ollama Model Error

If you get an error about the model not supporting tools, ensure you're using a model that supports function calling (like llama3.2, mistral, or qwen2.5-coder).

Connection Issues

Ensure the MCP server is running before starting the client.

Employee Not Added Issue

If your command to add an employee doesn't work:

• Check for email: Email is REQUIRED. Without it, the employee won't be saved.

• Look for error messages: "❌ Tool failed: Missing required field: email"

• Correct format: Add Name (email@company.com) to Department as Position

• Always include email: firstname.lastname@company.com

Tool Expects Employee ID Error

If you get errors when using employee names:

• Use the simplified tools: check_employee_leave_balance, update_employee_salary, submit_leave_request

• These accept names directly: "Check John Doe's leave balance"

• Don't use: get_leave_balance, update_salary, request_leave with names

• The simplified tools handle name-to-ID lookup automatically

License

MIT License