LLM SSE MCP Demo

What is LLM SSE MCP Demo?

LLM SSE MCP Demo is a multi-application demo project that integrates LLM clients with MCP (Model Context Protocol) servers using Server-Sent Events (SSE) for real-time communication. It includes an OAuth2 authorization server, an MCP server exposing math and date/time tools, and a web-based LLM client supporting Anthropic Claude, OpenAI GPT, Google Gemini, and Ollama. It targets developers building LLM-powered applications with external tool calling and observability.

How to use LLM SSE MCP Demo?

Start the observability stack (Prometheus, Tempo, Loki, Grafana) with Docker Compose, then run each Spring Boot app via ./gradlew bootRun in order: authorization server (port 9000), MCP server (port 8080), LLM client (port 10101). Set environment variables for cloud LLM API keys as needed. Open a browser to http://localhost:10101 to send queries like math operations or time requests.

Key features of LLM SSE MCP Demo

• OAuth 2.0 authorization for MCP services
• Mathematical tools: addition and multiplication
• Date/time tools: current time and alarm setting
• SSE-based real-time client-server communication
• Multi-provider LLM support (Claude, GPT, Gemini, Ollama)
• Integrated observability with Grafana, Prometheus, Tempo, Loki

Use cases of LLM SSE MCP Demo

• Building LLM applications that can perform calculations and time queries
• Demonstrating MCP protocol tool discovery and execution with SSE
• Exploring OAuth2 security for LLM-triggered tool calls
• Testing multi-model LLM integration in a single chat interface
• Learning observability setup for MCP-based Spring Boot services

FAQ from LLM SSE MCP Demo

What LLM models are supported?

Anthropic Claude (claude-sonnet-4-20250514), OpenAI (o4-mini-2025-04-16), Google Gemini (gemini-2.5-flash-preview-05-20), and Ollama (qwen3:8b locally).

What tools does the MCP server provide?

Four tools: sumNumbers(int, int) – adds two numbers; multiplyNumbers(int, int) – multiplies two numbers; getCurrentDateTime() – returns current date/time; setAlarm(String) – sets an alarm for an ISO-8601 time.

How do I start the demo?

Start the Docker Compose services for observability, then run each Spring Boot application in order: authorization server, MCP server, LLM client, using ./gradlew bootRun. Access the chat at http://localhost:10101 and Grafana at http://localhost:3000.

What are the prerequisites?

Java 17 or higher, Gradle, Docker and Docker Compose, API keys for cloud LLM providers (optional), and Ollama installed locally if using local models.

How do I access the web interface?

Open http://localhost:10101 in a browser after starting the LLM client. For Grafana dashboards (Prometheus, Tempo, Loki), use http://localhost:3000.