Turul MCP Framework - Beta Rust Implementation

A comprehensive Rust framework for building Model Context Protocol (MCP) servers and clients with modern patterns, extensive tooling, and enterprise-grade features. Fully compliant with MCP 2025-11-25 specification.

⚠️ Beta Status - Active development with ongoing feature enhancements. Full MCP 2025-11-25 compliance including task storage and runtime. Suitable for development and testing.

🧪 Active Development - Comprehensive Test Coverage

1729+ passing tests across workspace • Complete async SessionContext integration • Framework-native testing patterns

✨ Key Highlights

• 🏗️ 13 Framework Crates: Complete MCP ecosystem with core framework, client library, task storage, and serverless support
• 📚 58 Comprehensive Examples: Real-world business applications and framework demonstration examples (all validated through comprehensive testing campaign)
• 🧪 1729+ Development Tests: Comprehensive test suite with core framework tests, SessionContext integration tests, and framework-native integration tests
• ⚡ Multiple Development Patterns: Derive macros, function attributes, declarative macros, and manual implementation
• 🌐 Transport Flexibility: Streamable HTTP via StreamableHttpHandler with SSE streaming (stdio planned)
• ☁️ Serverless Support: AWS Lambda integration with streaming responses and SQS event processing
• 🔧 Development Features: Session management, real-time notifications, performance monitoring, and UUID v7 support
• ⚡ Performance Optimized: Comprehensive benchmarking suite with >1000 RPS throughput, <100ms response times, and extensive stress testing

🚀 Quick Start

1. Function Macros (Simplest - Recommended)

use turul_mcp_derive::mcp_tool;
use turul_mcp_server::prelude::*;

#[mcp_tool(name = "add", description = "Add two numbers")]
async fn add(
    #[param(description = "First number")] a: f64,
    #[param(description = "Second number")] b: f64,
) -> McpResult<f64> {
    Ok(a + b)  // Framework wraps as {"output": 8.0} in JSON-RPC response
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let server = McpServer::builder()
        .name("calculator-server")
        .version("1.0.0")
        .tool_fn(add)  // Use function name directly
        .bind_address("127.0.0.1:8641".parse()?)  // Default port; customize as needed
        .build()?;

    server.run().await
}

Task support: Add task_support = "optional" to enable the "Run as Task" button in MCP Inspector. Values: "optional", "required", "forbidden". Requires .with_task_storage() on the server builder.

2. Derive Macros (Struct-Based)

use turul_mcp_derive::McpTool;
use turul_mcp_server::prelude::*;

#[derive(McpTool, Clone)]
#[tool(name = "calculator", description = "Mathematical operations")]
struct Calculator {
    #[param(description = "First number")]
    a: f64,
    #[param(description = "Second number")]
    b: f64,
    #[param(description = "Operation (+, -, *, /)")]
    operation: String,
}

impl Calculator {
    async fn execute(&self, _session: Option<SessionContext>) -> McpResult<f64> {
        match self.operation.as_str() {
            "+" => Ok(self.a + self.b),
            "-" => Ok(self.a - self.b),
            "*" => Ok(self.a * self.b),
            "/" => {
                if self.b == 0.0 {
                    Err("Division by zero".into())
                } else {
                    Ok(self.a / self.b)
                }
            },
            _ => Err("Invalid operation".into()),
        }
    }
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let server = McpServer::builder()
        .name("calculator-server")
        .version("1.0.0")
        .tool(Calculator { a: 0.0, b: 0.0, operation: "+".to_string() })
        .bind_address("127.0.0.1:8642".parse()?)  // Different port to avoid conflicts
        .build()?;

    server.run().await
}

3. Resources with resource_fn()

Create resources that provide data and files using the .resource_fn() method:

use turul_mcp_derive::mcp_resource;
use turul_mcp_server::prelude::*;
use turul_mcp_protocol::resources::ResourceContent;

// Static resource
#[mcp_resource(
    uri = "file:///config.json",
    name = "config",
    description = "Application configuration"
)]
async fn get_config() -> McpResult<Vec<ResourceContent>> {
    let config = serde_json::json!({
        "app_name": "My Server",
        "version": "1.0.0"
    });

    Ok(vec![ResourceContent::blob(
        "file:///config.json",
        serde_json::to_string_pretty(&config).unwrap(),
        "application/json".to_string()
    )])
}

// Template resource with parameter extraction
#[mcp_resource(
    uri = "file:///users/{user_id}.json",
    name = "user_profile",
    description = "User profile data"
)]
async fn get_user_profile(user_id: String) -> McpResult<Vec<ResourceContent>> {
    let profile = serde_json::json!({
        "user_id": user_id,
        "username": format!("user_{}", user_id),
        "email": format!("{}@example.com", user_id)
    });

    Ok(vec![ResourceContent::blob(
        format!("file:///users/{}.json", user_id),
        serde_json::to_string_pretty(&profile).unwrap(),
        "application/json".to_string()
    )])
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let server = McpServer::builder()
        .name("resource-server")
        .version("1.0.0")
        .resource_fn(get_config)       // Static resource
        .resource_fn(get_user_profile) // Template: file:///users/{user_id}.json
        .bind_address("127.0.0.1:8643".parse()?)  // Different port to avoid conflicts
        .build()?;

    server.run().await
}

The framework automatically:

• Detects URI templates ({user_id} patterns)
• Extracts template variables from requests
• Maps them to function parameters
• Registers appropriate resource handlers

🚀 Running & Testing the Framework

Quick Start - Verify Everything Works

# 1. Build the framework
cargo build --workspace

# 2. Run compliance tests
cargo test -p turul-mcp-framework-integration-tests --test compliance

# 3. Start a simple server
cargo run -p minimal-server

# 4. Test the server (in another terminal)
curl -X POST http://127.0.0.1:8641/mcp \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","method":"initialize","params":{"protocolVersion":"2025-11-25","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}},"id":1}'

Example Servers - Ready to Run

Core Test Servers:

# Comprehensive server (all MCP features)
cargo run --package comprehensive-server -- --port 8002

# Resource server (17 test resources)  
cargo run --package resource-test-server -- --port 8080

# Prompts server (11 test prompts)
cargo run --package prompts-test-server -- --port 8081

Business Application Servers:

# Development team resources
cargo run -p resources-server -- --port 8041

# AI development prompts  
cargo run -p prompts-server -- --port 8040

# Real-time notifications
cargo run -p notification-server

# Session management demo
cargo run -p stateful-server

Manual MCP Compliance Verification

Step 1: Initialize Connection

PORT=8080  # Replace with your server's port
curl -X POST http://127.0.0.1:$PORT/mcp \
  -H 'Content-Type: application/json' \
  -d '{
    "jsonrpc": "2.0",
    "method": "initialize",
    "params": {
      "protocolVersion": "2025-11-25", 
      "capabilities": {},
      "clientInfo": {"name": "test", "version": "1.0"}
    },
    "id": 1
  }' | jq

Expected Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "protocolVersion": "2025-11-25",
    "serverInfo": {"name": "server-name", "version": "0.3"},
    "capabilities": {"tools": {"listChanged": false}}
  }
}

Step 2: Test Available Operations

# Get session ID from response and test capabilities
SESSION_ID="your-session-id-here"

# If server has tools capability:
curl -X POST http://127.0.0.1:$PORT/mcp \
  -H 'Content-Type: application/json' \
  -H "Mcp-Session-Id: $SESSION_ID" \
  -d '{"jsonrpc":"2.0","method":"tools/list","params":{},"id":2}' | jq

# If server has resources capability:
curl -X POST http://127.0.0.1:$PORT/mcp \
  -H 'Content-Type: application/json' \
  -H "Mcp-Session-Id: $SESSION_ID" \
  -d '{"jsonrpc":"2.0","method":"resources/list","params":{},"id":3}' | jq

Comprehensive Testing Guide

For detailed testing instructions, server running guides, and compliance verification:

📚 Complete Testing Guide

This guide includes:

• ✅ All server running instructions with expected outputs
• ✅ Manual MCP 2025-11-25 compliance verification
• ✅ SSE event stream testing procedures
• ✅ Performance testing and troubleshooting
• ✅ CI/CD integration examples

Quick Compliance Check Script

# Create and run compliance check
cat > quick_check.sh << 'EOF'
#!/bin/bash
PORT=${1:-8080}
echo "🧪 Testing MCP server on port $PORT"

INIT_RESPONSE=$(curl -s -X POST http://127.0.0.1:$PORT/mcp \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","method":"initialize","params":{"protocolVersion":"2025-11-25","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}},"id":1}')

if [[ $(echo $INIT_RESPONSE | jq -r '.result.protocolVersion') == "2025-11-25" ]]; then
    echo "✅ MCP 2025-11-25 compliant"
else
    echo "❌ Not compliant"
    exit 1
fi
EOF

chmod +x quick_check.sh

# Test any server
cargo run -p minimal-server &
./quick_check.sh 8641

🏛️ Architecture Overview

Middleware System

The framework provides a trait-based middleware architecture for cross-cutting concerns like authentication, logging, and rate limiting:

use turul_mcp_server::prelude::*;
use std::sync::Arc;

let server = McpServer::builder()
    .middleware(Arc::new(AuthMiddleware::new()))
    .middleware(Arc::new(LoggingMiddleware))
    .middleware(Arc::new(RateLimitMiddleware::new(5, 60)))
    .build()?;

Key Features:

• ✅ Transport-agnostic (HTTP, Lambda, etc.)
• ✅ Session-aware (read/write session state)
• ✅ Error short-circuiting with semantic JSON-RPC codes
• ✅ Execution order control (FIFO before, LIFO after dispatch)

Examples:

• examples/middleware-logging-server - Request timing and tracing (HTTP)
• examples/middleware-rate-limit-server - Per-session rate limiting (HTTP)
• examples/middleware-auth-server - API key authentication (HTTP)
• examples/middleware-auth-lambda - API key authentication (AWS Lambda)

Testing:

• Test HTTP middleware: bash scripts/test_middleware_live.sh
• Test Lambda middleware: cargo lambda watch --package middleware-auth-lambda

Documentation:

• ADR 012: Middleware Architecture - Core middleware design
• ADR 013: Lambda Authorizer Integration - API Gateway authorizer support

Lambda Authorizer Integration

Seamless API Gateway authorizer context extraction for Lambda deployments:

// API Gateway authorizer adds context (userId, tenantId, role, etc.)
// → turul-mcp-aws-lambda adapter extracts → injects x-authorizer-* headers
// → Middleware reads headers → stores in session state
// → Tools access via session.get_typed_state("authorizer")

#[async_trait]
impl McpMiddleware for AuthMiddleware {
    async fn before_dispatch(
        &self,
        ctx: &mut RequestContext<'_>,
        _session: Option<&dyn SessionView>,
        injection: &mut SessionInjection,
    ) -> Result<(), MiddlewareError> {
        // Extract authorizer context from x-authorizer-* headers
        let metadata = ctx.metadata();
        let mut authorizer_context = HashMap::new();

        for (key, value) in metadata.iter() {
            if let Some(field_name) = key.strip_prefix("x-authorizer-") {
                if let Some(value_str) = value.as_str() {
                    authorizer_context.insert(field_name.to_string(), value_str.to_string());
                }
            }
        }

        if !authorizer_context.is_empty() {
            // Store for tools to access
            injection.set_state("authorizer", json!(authorizer_context));
        }

        Ok(())
    }
}

Key Features:

• ✅ Supports API Gateway V1 (REST API) and V2 (HTTP API)
• ✅ Field name sanitization (camelCase → snake_case: userId → user_id)
• ✅ Defensive programming (never fails requests)
• ✅ Transport-agnostic (appears as standard HTTP metadata)
• ✅ Session state integration

Example:

• examples/middleware-auth-lambda - Full authorizer extraction pattern (V1 nested, V1 flat, V2)
• Test events: V1 nested, V1 flat, V2 authorizer shapes (test-events/)

Core Framework (13 Crates)

• turul-mcp-server - High-level server builder with session management and task runtime
• turul-mcp-client - Comprehensive client library with HTTP transport support
• turul-http-mcp-server - HTTP/SSE transport with CORS and streaming
• turul-mcp-protocol - Current MCP specification (alias to 2025-11-25)
• turul-mcp-protocol-2025-11-25 - Complete MCP 2025-11-25 specification implementation
• turul-mcp-protocol-2025-06-18 - Legacy MCP specification (backward compatibility)
• turul-mcp-derive - Procedural macros for all MCP areas
• turul-mcp-builders - Runtime builder patterns for dynamic MCP components
• turul-mcp-json-rpc-server - Transport-agnostic JSON-RPC 2.0 foundation
• turul-mcp-session-storage - Session storage backends (SQLite, PostgreSQL, DynamoDB)
• turul-mcp-task-storage - Task storage for long-running operations (InMemory, with pluggable backends)
• turul-mcp-aws-lambda - AWS Lambda integration for serverless deployment
• turul-mcp-oauth - OAuth 2.1 Resource Server support (JWT validation, Bearer middleware)

Tasks Architecture ADRs

Tasks are an experimental MCP 2025-11-25 capability. The framework provides full implementation support (protocol types, storage, runtime, handlers, and tests). See the architecture decision records for design rationale:

• ADR-015: Protocol Crate Strategy — separate crate for 2025-11-25 spec types including Tasks
• ADR-016: Task Storage Architecture — TaskStorage trait, 4 backends, state machine, parity test suite
• ADR-017: Task Runtime-Executor Boundary — three-layer split: storage / executor / runtime
• ADR-018: Task Pagination Cursor Contract — deterministic cursor-based pagination across backends

Fine-Grained Trait Architecture

Modern composable design pattern for all MCP areas:

use turul_mcp_builders::prelude::*;  // Framework traits + builders
use turul_mcp_protocol::{ToolSchema, ToolResult, schema::JsonSchema, McpResult};
use turul_mcp_server::{McpTool, SessionContext};
use async_trait::async_trait;
use serde_json::Value;
use std::collections::HashMap;

struct MyTool;

// Fine-grained trait composition for maximum flexibility
impl HasBaseMetadata for MyTool {
    fn name(&self) -> &str { "my_tool" }
}

impl HasDescription for MyTool {
    fn description(&self) -> Option<&str> { Some("Tool description") }
}

impl HasInputSchema for MyTool {
    fn input_schema(&self) -> &ToolSchema {
        static SCHEMA: std::sync::OnceLock<ToolSchema> = std::sync::OnceLock::new();
        SCHEMA.get_or_init(|| {
            ToolSchema::object()
                .with_properties(HashMap::from([
                    ("input".to_string(), JsonSchema::string())
                ]))
        })
    }
}

impl HasIcons for MyTool {}     // No icons (default)
impl HasExecution for MyTool {} // No task support (default)

// ToolDefinition automatically implemented via blanket impl
#[async_trait]
impl McpTool for MyTool {
    async fn call(&self, _args: Value, _session: Option<SessionContext>) 
        -> McpResult<CallToolResult> {
        Ok(CallToolResult::success(vec![
            ToolResult::text("Tool result")
        ]))
    }
}

Supported Areas:

• Tools (ToolDefinition) - Dynamic tool execution with validation
• Resources (ResourceDefinition) - Static and dynamic content serving
• Prompts (PromptDefinition) - AI interaction template generation
• Sampling (SamplingDefinition) - AI model integration patterns
• Completion (CompletionDefinition) - Context-aware text completion
• Logging (LoggerDefinition) - Dynamic log level management
• Roots (RootDefinition) - Secure file system access boundaries
• Elicitation (ElicitationDefinition) - Structured user input collection
• Notifications (NotificationDefinition) - Real-time event broadcasting

Comprehensive Server Builder

All MCP areas supported with consistent builder pattern:

let server = McpServer::builder()
    .name("comprehensive-server")
    .version("1.0.0")
    .instructions("Full-featured MCP server with all areas")
    // Tools
    .tool(WeatherTool::new())
    .tools(vec![CalculatorTool::new(), ValidationTool::new()])
    // Resources
    .resource(AppConfigResource::new())
    .resources(vec![LogsResource::new(), MetricsResource::new()])
    // Prompts
    .prompt(CodeReviewPrompt::new())
    .prompts(vec![DocumentationPrompt::new(), TestPrompt::new()])
    // Sampling
    .sampling_provider(CreativeSampling::new())
    .sampling_providers(vec![CodeSampling::new(), TechnicalSampling::new()])
    // Completion
    .completion_provider(IdeCompletion::new())
    .completion_providers(vec![SqlCompletion::new(), JsonCompletion::new()])
    // Logging
    .logger(AuditLogger::new())
    .loggers(vec![SecurityLogger::new(), PerformanceLogger::new()])
    // Roots
    .root_provider(WorkspaceRoot::new())
    .root_providers(vec![ConfigRoot::new(), TempRoot::new()])
    // Elicitation
    .elicitation(OnboardingElicitation::new())
    .elicitations(vec![SurveyElicitation::new(), FeedbackElicitation::new()])
    // Notifications
    .notification_provider(ProgressNotification::new())
    .notification_providers(vec![AlertNotification::new(), StatusNotification::new()])
    // Server configuration
    .bind_address("127.0.0.1:8080".parse()?)
    .build()?;

Complete MCP Implementation

All areas implemented with fine-grained trait architecture:

• ✅ Tools (ToolDefinition) - Dynamic tool execution with validation, schema generation, and metadata
• ✅ Resources (ResourceDefinition) - Static and dynamic content serving with access control
• ✅ Prompts (PromptDefinition) - AI interaction template generation with parameter validation
• ✅ Completion (CompletionDefinition) - Context-aware text completion with model preferences
• ✅ Logging (LoggerDefinition) - Dynamic log level management with structured output
• ✅ Notifications (NotificationDefinition) - Real-time SSE event broadcasting with filtering
• ✅ Roots (RootDefinition) - Secure file system access boundaries with permissions
• ✅ Sampling (SamplingDefinition) - AI model integration patterns with constraints
• ✅ Elicitation (ElicitationDefinition) - Structured user input collection with validation
• ✅ Session Management - Stateful operations with UUID v7 correlation IDs

Transport Support

• Streamable HTTP - Production transport via StreamableHttpHandler (HTTP/1.1 & HTTP/2 with chunked SSE, MCP 2025-11-25)
• HTTP+SSE (Legacy) - Backward-compatible transport via SessionMcpHandler (protocol <= 2024-11-05)
• AWS Lambda - Serverless deployment with streaming responses
• Stdio - Planned for future implementation

Note: The framework auto-selects transport handler based on protocol version negotiation.

📚 Examples Overview

🏢 Real-World Business Applications

Development servers for actual business problems:

1. comprehensive-server → Development Team Integration Platform
2. dynamic-resource-server → Enterprise API Data Gateway
3. logging-server → Application Audit & Compliance System
4. elicitation-server → Customer Onboarding Platform
5. notification-server → Development Team Alert System
6. completion-server → IDE Auto-Completion Server
7. prompts-server → AI-Assisted Development Prompts
8. derive-macro-server → Code Generation & Template Engine
9. calculator-add-*-server → Calculator examples (builder, function, derive, manual patterns)
10. resources-server → Development Team Resource Hub

🔧 Framework Demonstrations

Educational examples showcasing framework patterns:

• Basic Patterns: minimal-server, manual-tools-server, zero-config-getting-started
• Advanced Features: stateful-server, pagination-server, tasks-e2e-inmemory-server
• Macro System: derive-macro-server, function-macro-server, function-resource-server
• Serverless: lambda-mcp-server (AWS Lambda with SQS integration)
• Testing: performance-testing (comprehensive benchmarking suite)

☁️ Serverless Support

AWS Lambda MCP Server

Full serverless implementation with advanced AWS integration:

cd examples/lambda-mcp-server

# Local development
cargo lambda watch

# Deploy to AWS
cargo lambda build --release
sam deploy --guided

Features:

• 🔄 Dual event sources (HTTP + SQS)
• 📡 200MB streaming responses
• 🗄️ DynamoDB session management
• ⚡ Sub-200ms cold starts
• 📊 CloudWatch + X-Ray integration

🧪 Testing & Quality

🧪 Comprehensive Test Coverage - Development Quality

Framework Excellence: 1729+ tests across all components with complete async SessionContext integration:

• ✅ Core Framework Tests - Protocol, server, client, derive macros
• ✅ SessionContext Integration - Full session state management
• ✅ Framework Integration Tests - Proper API usage patterns
• ✅ MCP Compliance Tests - Protocol specification validation
• ✅ Builder Pattern Tests - Runtime tool creation
• ✅ E2E Integration Tests - Streamable HTTP, SSE, task lifecycle
• ✅ Example Applications - Real-world scenario validation

# Run all tests - expect 1729+ passing
cargo test --workspace

# SessionContext integration tests
cargo test -p turul-mcp-framework-integration-tests --test session_context_macro_tests

# Framework integration tests (proper patterns)
cargo test -p turul-mcp-framework-integration-tests --test feature_tests

# MCP compliance tests
cargo test -p turul-mcp-framework-integration-tests --test compliance

🎯 Framework-Native Testing Patterns

The RIGHT way to test MCP applications - Use framework APIs, not raw JSON:

// ✅ CORRECT: Framework integration test
use turul_mcp_server::prelude::*;
use turul_mcp_derive::McpTool;

#[derive(McpTool, Default)]
#[tool(name = "calculator", description = "Add numbers")]
struct Calculator {
    #[param(description = "First number")] a: f64,
    #[param(description = "Second number")] b: f64,
}

impl Calculator {
    async fn execute(&self, _session: Option<SessionContext>) -> McpResult<f64> {
        Ok(self.a + self.b)
    }
}

#[tokio::test]
async fn test_calculator_tool() {
    let tool = Calculator { a: 5.0, b: 3.0 };
    
    // Use framework's McpTool trait
    let result = tool.call(json!({"a": 5.0, "b": 3.0}), None).await.unwrap();
    
    // Verify using framework result types
    assert_eq!(result.content.len(), 1);
    match &result.content[0] {
        ToolResult::Text { text, .. } => {
            let parsed: Value = serde_json::from_str(text).unwrap();
            assert_eq!(parsed["output"], 8.0); // Derive macro uses "output"
        }
        _ => panic!("Expected text result")
    }
}

#[tokio::test] 
async fn test_server_integration() {
    // Use framework builders
    let server = McpServer::builder()
        .name("test-server")
        .tool(Calculator::default())
        .build()
        .unwrap();
    
    // Server builds successfully with proper type checking
    assert!(true);
}

❌ WRONG: Raw JSON manipulation (old problematic pattern):

// DON'T DO THIS - mixing incompatible JSON-RPC types
let request = json!({
    "method": "tools/call",
    "params": { "name": "calc" }
});

🔄 SessionContext Integration - Fully Working

Complete session state management with proper test infrastructure:

// SessionContext integration test
use crate::test_helpers::create_test_session;

#[tokio::test]
async fn test_session_state_management() {
    let session = create_test_session().await;
    
    // Session state works perfectly
session.set_typed_state("counter", &42i32).await.unwrap();
    let value: i32 = session.get_typed_state("counter").await.unwrap();
    assert_eq!(value, 42);
    
    // Progress notifications work
    session.notify_progress("processing", 50).await;
    
    // Tool execution with session context
    let tool = Calculator { a: 1.0, b: 2.0 };
    let result = tool.call(json!({"a": 1.0, "b": 2.0}), Some(session)).await.unwrap();
    assert_eq!(result.content.len(), 1);
}

Test Infrastructure Available:

• TestSessionBuilder - Create real SessionContext instances
• TestNotificationBroadcaster - Verify notifications
• create_test_session() - Helper for simple cases
• Full storage backend integration

🎯 Development Patterns

1. Function Macros (Recommended for Simplicity)

Best for: Quick development, natural syntax, minimal boilerplate

use turul_mcp_derive::mcp_tool;
use turul_mcp_server::prelude::*;

#[mcp_tool(name = "weather", description = "Get weather information")]
async fn get_weather(
    #[param(description = "City name")] city: String,
    #[param(description = "Temperature unit")] unit: Option<String>,
) -> McpResult<String> {
    let unit = unit.unwrap_or_else(|| "celsius".to_string());
    Ok(format!("Weather in {}: 22°{}", city, if unit == "fahrenheit" { "F" } else { "C" }))
}

// Usage in server
let server = McpServer::builder()
    .name("weather-server")
    .version("1.0.0")
    .tool_fn(get_weather)
    .build()?;

2. Derive Macros (Struct-Based)

Best for: Complex tools, organized codebases, multiple related functions

use turul_mcp_derive::McpTool;
use turul_mcp_server::prelude::*;

#[derive(McpTool, Clone)]
#[tool(name = "file_manager", description = "File management operations")]
struct FileManager {
    #[param(description = "Operation (create, read, delete)")]
    operation: String,
    #[param(description = "File path")]
    path: String,
    #[param(description = "File content (for create operation)")]
    content: Option<String>,
}

impl FileManager {
    async fn execute(&self, session: Option<SessionContext>) -> McpResult<String> {
        match self.operation.as_str() {
            "create" => {
                let content = self.content.as_ref().unwrap_or(&"Empty file".to_string());
                Ok(format!("Created file '{}' with content: {}", self.path, content))
            },
            "read" => Ok(format!("Reading file: {}", self.path)),
            "delete" => {
                if let Some(session) = session {
                    session.notify_progress(&format!("Deleting {}", self.path), 100).await;
                }
                Ok(format!("Deleted file: {}", self.path))
            },
            _ => Err("Invalid operation".into()),
        }
    }
}

// Usage in server
let server = McpServer::builder()
    .name("file-server")
    .version("1.0.0")
    .tool(FileManager {
        operation: "create".to_string(),
        path: "/tmp/example".to_string(),
        content: None,
    })
    .build()?;

3. Builder Pattern (Runtime Flexibility)

Best for: Dynamic tools, configuration-driven systems

use turul_mcp_server::prelude::*;
use serde_json::json;

let multiply_tool = ToolBuilder::new("multiply")
    .description("Multiply two numbers")
    .number_param("a", "First number")
    .number_param("b", "Second number")
    .number_output() // Generates {"result": number} schema
    .execute(|args| async move {
        let a = args.get("a").and_then(|v| v.as_f64())
            .ok_or("Missing parameter 'a'")?;
        let b = args.get("b").and_then(|v| v.as_f64())
            .ok_or("Missing parameter 'b'")?;
        
        Ok(json!({"result": a * b}))
    })
    .build()
    .map_err(|e| format!("Failed to build tool: {}", e))?;

// Usage in server
let server = McpServer::builder()
    .name("calculator-server")
    .version("1.0.0")
    .tool(multiply_tool)
    .build()?;

4. Manual Implementation (Maximum Control)

Best for: Performance optimization, custom behavior

use turul_mcp_server::prelude::*;  // Re-exports builders prelude + framework traits
use turul_mcp_protocol::{ToolSchema, ToolResult, schema::JsonSchema, McpResult};
use async_trait::async_trait;
use serde_json::Value;
use std::collections::HashMap;

struct ManualTool;

impl HasBaseMetadata for ManualTool {
    fn name(&self) -> &str { "manual_tool" }
}

impl HasDescription for ManualTool {
    fn description(&self) -> Option<&str> { Some("Manual implementation with full control") }
}

impl HasInputSchema for ManualTool {
    fn input_schema(&self) -> &ToolSchema {
        static SCHEMA: std::sync::OnceLock<ToolSchema> = std::sync::OnceLock::new();
        SCHEMA.get_or_init(|| {
            ToolSchema::object()
                .with_properties(HashMap::from([
                    ("input".to_string(), JsonSchema::string())
                ]))
        })
    }
}

impl HasOutputSchema for ManualTool {
    fn output_schema(&self) -> Option<&ToolSchema> { None }
}

impl HasAnnotations for ManualTool {
    fn annotations(&self) -> Option<&ToolAnnotations> { None }
}

impl HasToolMeta for ManualTool {
    fn tool_meta(&self) -> Option<&HashMap<String, Value>> { None }
}

impl HasIcons for ManualTool {}     // No icons
impl HasExecution for ManualTool {} // No task support

#[async_trait]
impl McpTool for ManualTool {
    async fn call(&self, _args: Value, _session: Option<SessionContext>) 
        -> McpResult<CallToolResult> {
        // Full control over implementation
        Ok(CallToolResult::success(vec![
            ToolResult::text("Manual tool with complete control")
        ]))
    }
}

// Usage in server
let server = McpServer::builder()
    .name("manual-server")
    .version("1.0.0")
    .tool(ManualTool)
    .build()?;

🔧 Client Library

Comprehensive MCP client for HTTP transport:

use turul_mcp_client::{McpClient, McpClientBuilder, transport::HttpTransport};
use std::time::Duration;

// Create HTTP transport
let transport = HttpTransport::new("http://localhost:8080/mcp")?;

// Create client using builder pattern
let client = McpClientBuilder::new()
    .with_transport(Box::new(transport))
    .build();

// Initialize session
let init_result = client.initialize().await?;

// List available tools
let tools = client.list_tools().await?;

// Call a tool
let result = client.call_tool("add", json!({
    "a": 10.0,
    "b": 20.0
})).await?;

// List and read resources
let resources = client.list_resources().await?;
let content = client.read_resource("config://app.json").await?;

🚀 Performance Features

Modern Architecture

• UUID v7 - Time-ordered IDs for better database performance and observability
• Workspace Dependencies - Consistent dependency management across 13 core crates and 58 examples
• Rust 2024 Edition - Latest language features and performance improvements
• Tokio/Hyper - High-performance async runtime with HTTP/2 support

Development Quality

• Session Management - Automatic cleanup and state persistence
• Real-time Notifications - SSE-based event streaming
• CORS Support - Browser client compatibility
• Comprehensive Logging - Structured logging with correlation IDs
• Error Handling - Detailed error types with recovery strategies

🔍 MCP Protocol Compliance

Full MCP 2025-11-25 specification support:

• ✅ JSON-RPC 2.0 - Complete request/response with _meta fields
• ✅ Protocol Negotiation - Version compatibility and capability exchange
• ✅ Progress Tracking - Long-running operation support
• ✅ Cursor Pagination - Efficient large dataset navigation
• ✅ Session Isolation - Secure multi-client support
• ✅ Transport Agnostic - Multiple transport implementations

Testing Your Server

# Test tool execution
curl -X POST http://127.0.0.1:8080/mcp \
  -H "Content-Type: application/json" \
  -H "MCP-Protocol-Version: 2025-11-25" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "add",
      "arguments": {"a": 10, "b": 20}
    }
  }'

# Test SSE notifications (after getting session ID from above request)
curl -N -H "Accept: text/event-stream" \
  -H "Mcp-Session-Id: <session-id>" \
  http://127.0.0.1:8080/mcp

MCP Session Management Compliance Testing

The framework includes comprehensive compliance testing for MCP session management specification requirements.

Running the Session Management Compliance Test

# 1. Start a server with session storage (choose backend: sqlite, postgres, dynamodb, or inmemory)
cargo run --example client-initialise-server -- --port 52950 --storage-backend dynamodb --create-tables

# 2. In another terminal, run the comprehensive compliance test (IMPORTANT: include RUST_LOG=info)
RUST_LOG=info cargo run --example session-management-compliance-test -- http://127.0.0.1:52950/mcp

# 3. Alternative: Use different storage backends
cargo run --example client-initialise-server -- --port 52951 --storage-backend sqlite --create-tables
RUST_LOG=info cargo run --example session-management-compliance-test -- http://127.0.0.1:52951/mcp

🛠️ Development & Testing

Building the Framework

# Build all workspace crates
cargo build

# Build with release optimizations
cargo build --release

Running Tests

The framework includes 1729+ comprehensive tests covering all functionality. Test server binaries are automatically built when needed - no manual setup required.

# Run all tests (recommended - includes E2E integration tests)
cargo test --workspace

# Run specific test suite
cargo test --package mcp-e2e-shared --test all -- concurrent_session

# Run with logging output
RUST_LOG=info cargo test --workspace

# Clean build and test (verifies auto-build works)
cargo clean && cargo test --workspace

Key Features:

• ✅ Auto-build test servers - Missing test binaries are built automatically on first test run
• ✅ Zero configuration - Just run cargo test and everything works
• ✅ Clean workspace support - cargo clean && cargo test works without manual steps

The test infrastructure automatically builds required test server binaries (resource-test-server, prompts-test-server, tools-test-server, etc.) when running integration tests. This ensures a seamless developer experience.

What the Compliance Test Verifies

The comprehensive test validates all MCP session management requirements:

• ✅ Session ID Generation: UUID v7 with cryptographic security and ASCII compliance
• ✅ Session Persistence: Proper session validation and storage backend integration
• ✅ Session Expiry: TTL-based cleanup and 404 responses for expired sessions
• ✅ Client Reinitialize: Graceful session recovery on expiry
• ✅ DELETE Termination: Explicit session termination support
• ✅ Session Isolation: Multi-session security and data separation

Expected Output

🧪 MCP Session Management Compliance Test
═══════════════════════════════════════════
✅ Session ID generation compliance verified
✅ Session persistence compliance verified  
✅ Session expiry compliance verified
✅ Client reinitialize compliance verified
✅ DELETE session termination compliance verified
✅ Session isolation compliance verified

🎉 MCP SESSION MANAGEMENT COMPLIANCE: COMPLETE
═══════════════════════════════════════════════

Storage Backend Configuration

DynamoDB (Development):

• 5-minute TTL with automatic cleanup
• GSI indexes for efficient queries
• AWS credentials required

SQLite (Development):

• File-based persistence
• 5-minute TTL with background cleanup
• No external dependencies

PostgreSQL (Enterprise):

• Full SQL features with indexing
• 5-minute TTL with efficient cleanup
• Connection string required

InMemory (Testing):

• Fast, no persistence
• 5-minute TTL with memory cleanup
• Zero configuration

Customizing TTL Configuration

// Custom TTL configuration (default: 5 minutes)
let config = DynamoDbConfig {
    session_ttl_minutes: 30,  // 30-minute session TTL
    event_ttl_minutes: 15,    // 15-minute event TTL
    ..Default::default()
};

Server-Sent Events (SSE) Verification

The framework includes comprehensive SSE testing to verify real-time notification streaming:

Running SSE Tests

# Test SSE functionality in prompts package
cargo test --package mcp-prompts-tests --test all -- sse

# Test specific SSE scenarios
cargo test --package mcp-prompts-tests test_sse_prompts_connection_establishment -- --nocapture
cargo test --package mcp-prompts-tests test_sse_prompts_list_changed_notification -- --nocapture
cargo test --package mcp-prompts-tests test_sse_prompts_session_isolation -- --nocapture

# Test SSE functionality in resources package
cargo test --package mcp-resources-tests --test all -- sse

# Test specific resource SSE scenarios
cargo test --package mcp-resources-tests test_sse_connection_establishment -- --nocapture
cargo test --package mcp-resources-tests test_sse_resource_list_changed_notification -- --nocapture
cargo test --package mcp-resources-tests test_sse_session_isolation -- --nocapture

Expected SSE Test Output

🚀 Starting MCP Resource Test Server on port 18994
✅ Session 01997404-d8f4-7b20-b76d-ac1f4be628a3 created and immediately initialized
✅ SSE connection: session=01997404-d908-7e62-ae74-af87f1523836, connection=01997404-d909-7001-8b95-296e806aa1e1
✅ Total notifications detected: 1
✅ Session ID correlation verified
✅ Valid SSE format compliance verified

test result: ok. 8 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out

Manual SSE Verification

# 1. Start any MCP server with SSE enabled
cargo run --example prompts-server

# 2. Get session ID via initialization
curl -X POST http://127.0.0.1:8080/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-11-25","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}}}'

# 3. Connect to SSE stream (replace SESSION_ID with actual ID)
curl -N -H "Accept: text/event-stream" \
  -H "Mcp-Session-Id: SESSION_ID" \
  http://127.0.0.1:8080/mcp

# Expected SSE output:
# id: 0
# event: ping
# data: {"type":"keepalive"}
#
# id: 1
# event: notification
# data: {"type":"resource_update","resource":"prompts/list"}

📊 Business Value Examples

Enterprise Integration

• dynamic-resource-server: API orchestration across Customer, Inventory, Financial, and HR systems
• logging-server: SOX, PCI DSS, GDPR, and HIPAA compliance reporting
• comprehensive-server: Team collaboration with project management and workflow automation

Developer Productivity

• completion-server: Context-aware IDE completions for multiple languages and frameworks
• prompts-server: AI-powered code review and architecture guidance
• derive-macro-server: Template-based code generation with validation

Customer Experience

• elicitation-server: GDPR-compliant customer onboarding with regulatory forms
• notification-server: Real-time incident management with escalation workflows

🛡️ Security & Reliability

• Memory Safety - Rust's ownership system prevents common vulnerabilities
• Type Safety - Compile-time validation with automatic schema generation
• Input Validation - Parameter constraints and sanitization
• Session Isolation - Secure multi-tenant operation
• Audit Logging - Comprehensive activity tracking with UUID v7 correlation
• Resource Limits - Configurable timeouts and memory constraints

🤝 Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Add tests for your changes
4. Run the full test suite (cargo test --workspace)
5. Benchmark performance impact if applicable
6. Commit changes (git commit -m 'Add amazing feature')
7. Push to branch (git push origin feature/amazing-feature)
8. Open a Pull Request

📝 License

This project is licensed under the MIT OR Apache-2.0 License - see the LICENSE files for details.

🙏 Acknowledgments

• Model Context Protocol - The foundational specification
• Tokio - Async runtime powering the framework
• Hyper - HTTP foundation with HTTP/2 support
• Serde - Serialization framework
• Rust Community - For exceptional tooling and ecosystem

📋 Development Status & Current Limitations

🎯 Current Framework State

• Phase 6 Complete: Session-aware resources implemented with full MCP 2025-11-25 compliance
• 58 Examples Validated: Comprehensive testing campaign completed across all framework areas
• SSE Streaming Verified: Real-time notifications and session-aware logging working correctly
• Beta Status: Active development with API stability considerations before 1.0.0

🚧 Current Limitations

Transport & Streaming:

• Lambda SSE: Snapshot-based responses via handle(), real-time streaming via run_streaming() / run_streaming_with() with graceful completion-invocation handling
• Additional transport variants: Streamable HTTP and legacy HTTP+SSE are supported; stdio remains planned
• CI Environment Testing: SSE tests require port binding capabilities (graceful fallbacks implemented)

Features & Integration:

• Resource Subscriptions: resources/subscribe MCP spec feature planned for future implementation
• Authentication Middleware: OAuth 2.1 Resource Server support via turul-mcp-oauth (JWT validation, Bearer token middleware, .well-known metadata)
• Cross-platform Compatibility: Primarily tested on Linux development environments

📊 Areas for Enhancement

• Performance Monitoring: Basic benchmarks available, comprehensive monitoring planned
• Concurrency Stress Testing: Some resource tests show occasional failures under extreme load
• Browser Compatibility: CORS support available but may need tuning for specific client requirements

Framework Philosophy: We prioritize honest documentation over inflated claims. This beta status reflects our commitment to transparency about the current development state.

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🚀 Ready to build MCP servers? Start with our comprehensive examples or check the getting started guide.

💡 Need help? Open an issue or check our 58 validated examples covering everything from simple calculators to enterprise systems.