# Breaking Changes for Spring AI MCP 0.5.0-SNAPSHOT

## Major Changes

1. Transport Implementation Modularization
   - SSE transport implementations have been moved to dedicated modules:
     - `mcp-webflux-sse-transport`: WebFlux-based SSE transport
     - `mcp-webmvc-sse-transport`: WebMVC-based SSE transport
   - Base MCP module no longer includes transport implementations

2. Class Renames
   - `SseClientTransport` → `WebFluxSseClientTransport`
   - `SseServerTransport` → `WebFluxSseServerTransport`

3. Project Structure
   - Test utilities moved to new `mcp-test` module
   - All samples moved to the the https://github.com/spring-projects/spring-ai-examples/tree/main/model-context-protocol

## Migration Guide

### 1. Update Dependencies

If using SSE transport, add the appropriate transport module to your pom.xml:

For WebFlux SSE transport:
```xml
<dependency>
    <groupId>org.springframework.experimental</groupId>
    <artifactId>mcp-webflux-sse-transport</artifactId>
    <version>0.5.0-SNAPSHOT</version>
</dependency>
```

For WebMVC SSE transport:
```xml
<dependency>
    <groupId>org.springframework.experimental</groupId>
    <artifactId>mcp-webmvc-sse-transport</artifactId>
    <version>0.5.0-SNAPSHOT</version>
</dependency>
```

### 2. Update Transport Class References

Replace:
```java
import org.springframework.ai.mcp.client.transport.SseClientTransport;
import org.springframework.ai.mcp.server.transport.SseServerTransport;
```

With:
```java
// For WebFlux
import org.springframework.ai.mcp.client.transport.WebFluxSseClientTransport;
import org.springframework.ai.mcp.server.transport.WebFluxSseServerTransport;

// Or for WebMVC
import org.springframework.ai.mcp.server.transport.WebMvcSseServerTransport;
```

### 3. Update Transport Instantiation

Replace:
```java
var transport = new SseClientTransport(webClientBuilder);
```

With:
```java
var transport = new WebFluxSseClientTransport(webClientBuilder);
```

Replace:
```java
var serverTransport = new SseServerTransport(objectMapper, messageEndpoint);
```

With:
```java
// For WebFlux
var serverTransport = new WebFluxSseServerTransport(objectMapper, messageEndpoint);

// Or for WebMVC
var serverTransport = new WebMvcSseServerTransport(objectMapper, messageEndpoint);
```

### 4. Test Dependencies

If you're using MCP test utilities, add the test module dependency:

```xml
<dependency>
    <groupId>org.springframework.experimental</groupId>
    <artifactId>mcp-test</artifactId>
    <version>0.5.0-SNAPSHOT</version>
    <scope>test</scope>
</dependency>
```

## Other Changes

- Spring AI dependency updated to 1.0.0-M5
- Improved dependency management and reduced transitive dependencies
- Sample application restructured under samples/ directory
- New test utilities and base test classes in mcp-test module