Tracks and categorizes Svelte component warnings and errors during development, enabling immediate debugging assistance
Monitors and categorizes TypeScript compilation errors in real-time, providing structured error data with file locations and severity classification
Monitors Vite build failures and development server issues, providing real-time error notifications and categorization
Click on "Install Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@DevServer MCPshow me the recent errors in my Svelte components"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
DevServer MCP
An MCP server that monitors development server logs in real-time, categorizes errors by type and severity, and provides Claude Code with immediate error notifications via Server-Sent Events (SSE).
DevServer MCP:
Real-time notifications: Instant error alerts via SSE transport
Intelligent parsing: Recognizes TypeScript, Svelte, Vite error patterns
Error correlation: Links errors to recent file changes
Severity classification: Critical vs warning vs info
Multiple client support: Connect multiple Claude Code instances simultaneously
AI integration: Claude Code receives structured error data instead of raw logs
Quick Start
# Install and build
pnpm install && pnpm build
# Start monitoring with SSE server (uses default port 9338)
node dist/server.js --monitor pnpm run dev
# Connect Claude Code (port stays consistent across restarts)
claude mcp add --transport sse devserver-mcp http://127.0.0.1:9338/sseNow Claude Code receives immediate notifications when errors occur!
Core Workflow
Traditional debugging:
Notice something broken → 2. Scroll through terminal → 3. Find relevant error → 4. Google it
With DevServer MCP:
Error occurs → 2. Instant notification in Claude Code → 3. Get categorized errors with file locations → 4. Ask "How do I fix this?"
MCP Tools
get_dev_server_status- Current server health and error countsget_error_summary- Errors grouped by type/severityget_error_history- Chronological error list with filteringget_file_errors- Errors for a specific filesuggest_monitoring_setup- Project-specific setup recommendations
Port Configuration
Default Port (9338):
# Start with default port
node dist/server.js --monitor pnpm run dev
# Connect Claude Code
claude mcp add --transport sse devserver-mcp http://127.0.0.1:9338/sseCustom Port Per Project:
# Frontend project on port 9339
node dist/server.js --port 9339 --monitor pnpm run dev
# Backend project on port 9340
node dist/server.js --port 9340 --monitor npm run dev:api
# Connect to specific projects
claude mcp add --transport sse frontend-devserver http://127.0.0.1:9339/sse
claude mcp add --transport sse backend-devserver http://127.0.0.1:9340/sseBenefits:
✅ Consistent ports - same port every restart, no need to re-add MCP server
✅ Per-project ports - run multiple projects simultaneously
✅ Conflict detection - helpful error messages if port is already in use
Architecture
SSE-Based Real-Time System:
Monitor mode (
--monitor): Spawns dev server, parses logs, broadcasts errors via SSEHTTP server: Serves
/sseendpoint for Claude Code connections on specified portError buffering: Maintains recent error history for newly connected clients
Multi-client support: Multiple Claude Code instances can connect simultaneously
Real-time error streaming means Claude Code gets notified within 1-2 seconds of any dev server issue.
Error Categories
Built-in patterns for:
TypeScript compilation errors
Svelte component warnings
Vite build failures
Network/API errors
Runtime JavaScript errors
Accessibility issues
Configuration
Create devserver-mcp.config.json:
{
"processPatterns": ["pnpm run dev", "npm run dev"],
"historyLimit": 1000,
"correlationWindow": 5000,
"watchPaths": ["src", "lib"],
"excludePaths": ["node_modules", ".git"],
"patterns": [
{
"name": "custom-error",
"pattern": "CUSTOM: (.+)",
"category": "runtime",
"severity": "critical"
}
]
}Development
pnpm install # Install deps
pnpm build # Build project
pnpm dev # Watch mode
pnpm test # Run tests
pnpm typecheck # Type checkingTroubleshooting
Connection Failed
# Check if monitoring server is running
ps aux | grep "node.*server.js"
# Restart monitoring server (default port 9338)
node dist/server.js --monitor pnpm run dev
# Verify connection
claude mcp add --transport sse devserver-mcp http://127.0.0.1:9338/ssePort Already in Use
# Error: Port 9338 is already in use!
# Solution: Use a different port
node dist/server.js --port 9339 --monitor pnpm run dev
# Then connect with the new port
claude mcp add --transport sse devserver-mcp http://127.0.0.1:9339/sseNo Real-Time Notifications
# Check MCP connection status
claude mcp list
# Remove and reconnect if needed
claude mcp remove devserver-mcp
claude mcp add --transport sse devserver-mcp http://127.0.0.1:9338/sseMultiple Projects
# Each project should use a different port
# Project A
node dist/server.js --port 9338 --monitor pnpm run dev
# Project B
node dist/server.js --port 9339 --monitor npm run dev
# Connect both in Claude Code with different names
claude mcp add --transport sse project-a http://127.0.0.1:9338/sse
claude mcp add --transport sse project-b http://127.0.0.1:9339/sseLicense
MIT
This server cannot be installed
Resources
Unclaimed servers have limited discoverability.
Looking for Admin?
If you are the server author, to access and configure the admin panel.