# MCP Integration

> This skill should be used when the user asks to "add MCP server", "integrate MCP", "configure MCP in plugin", "use .mcp.json", "set up Model Context Protocol", "connect external service", mentions "${CLAUDE_PLUGIN_ROOT} with MCP", or discusses MCP server types (SSE, stdio, HTTP, WebSocket). Provides comprehensive guidance for integrating Model Context Protocol servers into Claude Code plugins for external tool and service integration.

- Skill: `dreydrey9000/mcp-integration` (Agent Skill, multi-file: 9 files)
- Install (CLI): `npx skillmds@latest add dreydrey9000/mcp-integration`
- Raw SKILL.md: https://api.skillmd.com/api/skills/dreydrey9000/mcp-integration/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: Dreydrey9000 (https://skillmd.com/u/dreydrey9000)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/dreydrey9000/mcp-integration

---


# MCP Integration for Claude Code Plugins

## Overview

Model Context Protocol (MCP) enables Claude Code plugins to integrate with external services and APIs by providing structured tool access. Use MCP integration to expose external service capabilities as tools within Claude Code.

**Key capabilities:**
- Connect to external services (databases, APIs, file systems)
- Provide 10+ related tools from a single service
- Handle OAuth and complex authentication flows
- Bundle MCP servers with plugins for automatic setup

## MCP Server Configuration Methods

Plugins can bundle MCP servers in two ways:

## MCP Server Types

## MCP Tool Naming

When MCP servers provide tools, they're automatically prefixed:

**Format:** `mcp__plugin_<plugin-name>_<server-name>__<tool-name>`

**Example:**
- Plugin: `asana`
- Server: `asana`
- Tool: `create_task`
- **Full name:** `mcp__plugin_asana_asana__asana_create_task`

## Authentication Patterns

### OAuth (SSE/HTTP)

OAuth handled automatically by Claude Code:

```json
{
  "type": "sse",
  "url": "https://mcp.example.com/sse"
}
```

User authenticates in browser on first use. No additional configuration needed.

## Integration Patterns

## Security Best Practices

### Use HTTPS/WSS

Always use secure connections:

```json
✅ "url": "https://mcp.example.com/sse"
❌ "url": "http://mcp.example.com/sse"
```

### Token Management

**DO:**
- ✅ Use environment variables for tokens
- ✅ Document required env vars in README
- ✅ Let OAuth flow handle authentication

**DON'T:**
- ❌ Hardcode tokens in configuration
- ❌ Commit tokens to git
- ❌ Share tokens in documentation

### Permission Scoping

Pre-allow only necessary MCP tools:

```markdown
✅ allowed-tools: [
  "mcp__plugin_api_server__read_data",
  "mcp__plugin_api_server__create_item"
]

❌ allowed-tools: ["mcp__plugin_api_server__*"]
```

## Error Handling

### Connection Failures

Handle MCP server unavailability:
- Provide fallback behavior in commands
- Inform user of connection issues
- Check server URL and configuration

### Tool Call Errors

Handle failed MCP operations:
- Validate inputs before calling MCP tools
- Provide clear error messages
- Check rate limiting and quotas

### Configuration Errors

Validate MCP configuration:
- Test server connectivity during development
- Validate JSON syntax
- Check required environment variables

## Performance Considerations

### Lazy Loading

MCP servers connect on-demand:
- Not all servers connect at startup
- First tool use triggers connection
- Connection pooling managed automatically

## Testing MCP Integration

### Local Testing

1. Configure MCP server in `.mcp.json`
2. Install plugin locally (`.claude-plugin/`)
3. Run `/mcp` to verify server appears
4. Test tool calls in commands
5. Check `claude --debug` logs for connection issues

### Validation Checklist

- [ ] MCP configuration is valid JSON
- [ ] Server URL is correct and accessible
- [ ] Required environment variables documented
- [ ] Tools appear in `/mcp` output
- [ ] Authentication works (OAuth or tokens)
- [ ] Tool calls succeed from commands
- [ ] Error cases handled gracefully

## Debugging

### Enable Debug Logging

```bash
claude --debug
```

Look for:
- MCP server connection attempts
- Tool discovery logs
- Authentication flows
- Tool call errors

### MCP Server Types

| Type | Transport | Best For | Auth |
|------|-----------|----------|------|
| stdio | Process | Local tools, custom servers | Env vars |
| SSE | HTTP | Hosted services, cloud APIs | OAuth |
| HTTP | REST | API backends, token auth | Tokens |
| ws | WebSocket | Real-time, streaming | Tokens |

### Configuration Checklist

- [ ] Server type specified (stdio/SSE/HTTP/ws)
- [ ] Type-specific fields complete (command or url)
- [ ] Authentication configured
- [ ] Environment variables documented
- [ ] HTTPS/WSS used (not HTTP/WS)
- [ ] ${CLAUDE_PLUGIN_ROOT} used for paths

## Additional Resources

### Example Configurations

Working examples in `examples/`:

- **`stdio-server.json`** - Local stdio MCP server
- **`sse-server.json`** - Hosted SSE server with OAuth
- **`http-server.json`** - REST API with token auth

### External Resources

- **Official MCP Docs**: https://modelcontextprotocol.io/
- **Claude Code MCP Docs**: https://docs.claude.com/en/docs/claude-code/mcp
- **MCP SDK**: @modelcontextprotocol/sdk
- **Testing**: Use `claude --debug` and `/mcp` command


## Full Specification

Complete details, decision trees, protocols, and implementation specs: [references/full-details.md](references/full-details.md)