# MCP Integration Implementation Summary

## ✅ Status: Core Implementation Complete

Successfully implemented comprehensive MCP (Model Context Protocol) integration for Seline, enabling dynamic connection to external MCP servers and seamless tool discovery.

## What's Working Now

### ✅ MCP Server Connection (Both Transports)
- **Stdio Transport**: Subprocess-based servers (e.g., `npx @assistant-ui/mcp-docs-server`)
- **HTTP/SSE Transport**: URL-based servers (e.g., Supabase MCP)

### ✅ Settings UI
- **New URL Card-Based Interface**: Replaced raw JSON with a beautiful card-based UI
- **Quick Start Templates**: One-click setup for popular servers (GitHub, Postgres, Filesystem)
- **Easy Management**: Add, connect, and delete servers with simple buttons
- **Environment Variables**: Dedicated section for managing API keys
- **Status Indicators**: Visual feedback for connection state and tool counts
- **Dual-Mode Config**: Simple Card UI + Advanced JSON editor

### ✅ Backend Robustness
- **Connection cleanup**: Added graceful disconnect delay to allow port release
- **Stdio Transport**: Improved process management for subprocess servers
- **Separate Endpoints**: Split connect/config routes for better error handling

### ✅ Chat Integration
- MCP tools are automatically loaded for each agent
- Tools are merged with Seline's native tools
- Tool results are formatted to match Seline conventions

## Files Created

| File | Description |
|------|-------------|
| `lib/mcp/types.ts` | Type definitions for MCP config, tools, status |
| `lib/mcp/client-manager.ts` | Singleton for managing MCP connections |
| `lib/mcp/result-formatter.ts` | Formats MCP results to Seline conventions |
| `lib/mcp/chat-integration.ts` | Helper for loading MCP tools in chat |
| `lib/ai/tool-registry/mcp-tool-adapter.ts` | Converts MCP tools to AI SDK format |
| `app/api/mcp/route.ts` | GET/PUT for MCP configuration |
| `app/api/mcp/connect/route.ts` | POST to connect to servers |
| `app/api/mcp/tools/route.ts` | GET discovered tools |
| `components/settings/mcp-settings.tsx` | Settings UI component |
| `components/ui/mcp-tool-badge.tsx` | Visual badge for MCP tools |
| `components/character-creation/terminal-pages/mcp-tools-page.tsx` | Agent wizard MCP page |

## Files Modified

| File | Changes |
|------|---------|
| `lib/settings/settings-manager.ts` | Added `mcpServers` and `mcpEnvironment` fields |
| `lib/characters/validation.ts` | Extended schema for per-agent MCP config |
| `lib/ai/tool-registry/types.ts` | Added "mcp" to ToolCategory |
| `app/api/chat/route.ts` | Integrated MCP tool loading |
| `app/settings/page.tsx` | Added MCP settings section |

## Configuration Example

### Stdio Transport (Subprocess)
```json
{
  "mcpServers": {
    "assistant-ui": {
      "command": "npx",
      "args": ["-y", "@assistant-ui/mcp-docs-server"]
    }
  }
}
```

### HTTP/SSE Transport
```json
{
  "mcpServers": {
    "supabase": {
      "type": "sse",
      "url": "https://mcp.supabase.com/sse?project_ref=${SUPABASE_PROJECT_REF}",
      "headers": {
        "Authorization": "Bearer ${SUPABASE_ACCESS_TOKEN}"
      }
    }
  }
}
```

## Remaining Tasks

### Optional Enhancements
- [ ] Add MCP tools page to agent creation wizard
- [ ] Show MCP tool badges in chat tool results
- [ ] Add per-agent MCP server/tool selection
- [ ] Connection retry logic
- [ ] Tool discovery caching

## Architecture

```
┌─────────────────────────────────────────────────────────────┐
│                    SELINE APPLICATION                        │
├─────────────────────────────────────────────────────────────┤
│                                                             │
│  Settings Page → MCP Config Store → MCP Client Manager     │
│       ↓                                     ↓               │
│  Save Config                         Connect (stdio/sse)    │
│                                           ↓                 │
│                                    Tool Discovery           │
│                                           ↓                 │
│                                  MCP Tool Adapter           │
│                                           ↓                 │
│                               Merge with Tool Registry      │
│                                           ↓                 │
│                                    Chat Route               │
│                                         ↓                   │
│                                  AI Uses MCP Tools          │
│                                                             │
└─────────────────────────────────────────────────────────────┘
```

## Testing Verified

✅ Connect to stdio MCP server (`@assistant-ui/mcp-docs-server`)
✅ Tool discovery (2 tools found)
✅ Settings UI loads and saves configuration
✅ Connect button triggers server connection
✅ Status display shows connected servers and tool counts

---

**Implementation Date**: 2026-01-16
**Status**: ✅ Core Complete, Ready for Use
