# Testing MCP Server with SSE Transport Locally
This guide shows how to test the Jakarta Migration MCP server using SSE (Server-Sent Events) transport instead of stdio, which may bypass the GetInstructions/ListOfferings timeout issue.
## Why SSE?
Some Spring AI MCP projects report better behavior with SSE transport:
- Different initialization flow
- May bypass GetInstructions/ListOfferings issues
- HTTP-based communication (easier to debug)
- Can test with curl/browser
## Step 1: Start the Server with SSE
### Option A: Using Spring Profile
```powershell
cd E:\Source\JakartaMigrationMCP
java -jar build\libs\jakarta-migration-mcp-1.0.0-SNAPSHOT.jar --spring.profiles.active=mcp-sse
```
### Option B: Using Environment Variables
```powershell
$env:MCP_TRANSPORT="sse"
$env:MCP_SSE_PORT="8080"
$env:MCP_SSE_PATH="/mcp/sse"
java -jar build\libs\jakarta-migration-mcp-1.0.0-SNAPSHOT.jar
```
### Option C: Using Command Line Args
```powershell
java -jar build\libs\jakarta-migration-mcp-1.0.0-SNAPSHOT.jar `
--spring.ai.mcp.server.transport=sse `
--spring.ai.mcp.server.sse.port=8080 `
--spring.ai.mcp.server.sse.path=/mcp/sse
```
## Step 2: Verify Server is Running
### Check Server Logs
You should see:
```
Tomcat started on port(s): 8080
MCP Server started with transport: sse
```
### Test Health Endpoint
```powershell
curl http://localhost:8080/actuator/health
```
Should return:
```json
{"status":"UP"}
```
### Test MCP SSE Endpoint
```powershell
curl -N http://localhost:8080/mcp/sse
```
This should start an SSE stream (may look like JSON-RPC messages).
## Step 3: Configure Cursor for SSE
### Update Cursor MCP Configuration
1. Open Cursor Settings (`Ctrl+,`)
2. Navigate to **Features** → **MCP**
3. Replace the jakarta-migration configuration with:
```json
{
"mcpServers": {
"jakarta-migration": {
"type": "sse",
"url": "http://localhost:8080/mcp/sse"
}
}
}
```
**Or** use the provided config file:
- Copy contents from `CURSOR_MCP_CONFIG_SSE.json`
- Paste into Cursor MCP settings
### Important Notes
- **Server must be running first**: Start the server before configuring Cursor
- **Port must match**: Ensure port 8080 matches your server configuration
- **Restart Cursor**: After changing MCP config, restart Cursor completely
## Step 4: Test in Cursor
1. **Restart Cursor completely**
2. **Check MCP status**: Should show jakarta-migration as connected
3. **Test tool discovery**: Ask "What Jakarta migration tools are available?"
4. **Test a tool**: Try "Analyze Jakarta readiness for examples/..."
## Troubleshooting
### Issue: Server won't start
**Check**:
- Port 8080 is not already in use
- Java is installed and in PATH
- JAR file exists at the path
**Solution**:
```powershell
# Check if port is in use
netstat -ano | findstr :8080
# Use different port if needed
$env:MCP_SSE_PORT="9090"
# Then update Cursor config to use port 9090
```
### Issue: Cursor can't connect
**Check**:
- Server is running (check logs)
- Health endpoint works: `curl http://localhost:8080/actuator/health`
- URL in Cursor config matches server path
**Solution**:
- Verify server logs show "MCP Server started with transport: sse"
- Test SSE endpoint: `curl -N http://localhost:8080/mcp/sse`
- Check Cursor MCP logs for connection errors
### Issue: Still getting timeout
**If SSE also times out**:
- This confirms it's a Spring AI MCP framework bug
- Both stdio and SSE are affected
- Need to wait for Spring AI fix or file bug report
## Comparing stdio vs SSE
| Aspect | stdio | SSE |
|--------|-------|-----|
| **Setup** | Simple (just run JAR) | Need to start server first |
| **Debugging** | Harder (stdin/stdout) | Easier (HTTP endpoints) |
| **Port Required** | No | Yes (8080) |
| **Initialization** | Process-based | HTTP-based |
| **Timeout Issue** | Yes (1 minute) | May be different |
## Expected Behavior
### If SSE Works Better
- Tools load without timeout
- GetInstructions/ListOfferings work or are bypassed
- Tools are accessible in Cursor
### If SSE Has Same Issue
- Confirms it's a Spring AI MCP framework bug
- Both transports affected
- Need framework fix
## Next Steps
After testing SSE:
1. **If it works**: Document SSE as the recommended transport
2. **If it doesn't**: File bug report with Spring AI team
3. **Either way**: Update documentation with findings
## Reverting to stdio
To go back to stdio:
1. Update Cursor config to use stdio (see `CURSOR_MCP_CONFIG.json`)
2. Restart Cursor
3. No need to start server separately (stdio runs as process)
