# Genkit MCP Plugin
Model Context Protocol (MCP) integration for Go Genkit
Connect to MCP servers and expose Genkit tools as MCP servers.
## GenkitMCPClient - Single Server Connection
Connect to and use tools/prompts from a single MCP server:
```go
package main
import (
"context"
"log"
"github.com/firebase/genkit/go/genkit"
"github.com/firebase/genkit/go/plugins/mcp"
)
func main() {
ctx := context.Background()
g := genkit.Init(ctx)
// Connect to the MCP everything server
client, err := mcp.NewGenkitMCPClient(mcp.MCPClientOptions{
Name: "everything-server",
Stdio: &mcp.StdioConfig{
Command: "npx",
Args: []string{"-y", "@modelcontextprotocol/server-everything"},
},
})
if err != nil {
log.Fatal(err)
}
// Get specific prompts from the everything server
simplePrompt, err := client.GetPrompt(ctx, g, "simple-prompt", nil)
if err != nil {
log.Fatal(err)
}
// Get all available tools
tools, err := client.GetActiveTools(ctx, g)
if err != nil {
log.Fatal(err)
}
}
```
## GenkitMCPManager - Multiple Server Management
Manage connections to multiple MCP servers:
```go
package main
import (
"context"
"log"
"github.com/firebase/genkit/go/genkit"
"github.com/firebase/genkit/go/plugins/mcp"
)
func main() {
ctx := context.Background()
g, _ := genkit.Init(ctx)
// Create manager with multiple servers
manager, err := mcp.NewMCPManager(mcp.MCPManagerOptions{
Name: "my-app",
MCPServers: map[string]mcp.MCPClientOptions{
"everything": {
Name: "everything-server",
Stdio: &mcp.StdioConfig{
Command: "npx",
Args: []string{"-y", "@modelcontextprotocol/server-everything"},
},
},
"filesystem": {
Name: "fs-server",
Stdio: &mcp.StdioConfig{
Command: "npx",
Args: []string{"@modelcontextprotocol/server-filesystem", "/tmp"},
},
},
},
})
if err != nil {
log.Fatal(err)
}
// Connect to new server at runtime
err = manager.ConnectServer(ctx, "weather", mcp.MCPClientOptions{
Name: "weather-server",
Stdio: &mcp.StdioConfig{
Command: "python",
Args: []string{"weather_server.py"},
},
})
if err != nil {
log.Fatal(err)
}
// Temporarily disable/enable servers
manager.DisableServer("filesystem")
manager.EnableServer("filesystem")
// Disconnect server
manager.DisconnectServer("weather")
// Get tools from all active servers
tools, err := manager.GetActiveTools(ctx, g)
if err != nil {
log.Fatal(err)
}
}
```
## GenkitMCPServer - Expose Genkit Tools
Turn your Genkit app into an MCP server:
```go
package main
import (
"context"
"log"
"github.com/firebase/genkit/go/genkit"
"github.com/firebase/genkit/go/plugins/mcp"
)
func main() {
ctx := context.Background()
g := genkit.Init(ctx)
// Create a host with multiple servers
host, err := mcp.NewMCPHost(g, mcp.MCPHostOptions{
Name: "my-app",
MCPServers: []mcp.MCPServerConfig{
{
Name: "everything-server",
Config: mcp.MCPClientOptions{
Name: "everything-server",
Stdio: &mcp.StdioConfig{
Command: "npx",
Args: []string{"-y", "@modelcontextprotocol/server-everything"},
},
},
},
{
Name: "fs-server",
Config: mcp.MCPClientOptions{
Name: "fs-server",
Stdio: &mcp.StdioConfig{
Command: "npx",
Args: []string{"@modelcontextprotocol/server-filesystem", "/tmp"},
},
},
},
},
})
if err != nil {
log.Fatal(err)
}
// Connect to new server at runtime
err = host.Connect(ctx, g, "weather", mcp.MCPClientOptions{
Name: "weather-server",
Stdio: &mcp.StdioConfig{
Command: "python",
Args: []string{"weather_server.py"},
},
})
if err != nil {
log.Fatal(err)
}
// Reconnect server
host.Reconnect(ctx, "fs-server")
// Disconnect server
host.Disconnect(ctx, "weather")
// Get tools from all active servers
tools, err := host.GetActiveTools(ctx, g)
if err != nil {
log.Fatal(err)
}
}
```
## Testing Your Server
```bash
# Run your server
go run main.go
# Test with MCP Inspector
npx @modelcontextprotocol/inspector go run main.go
```
## Transport Options
### Stdio (Standard)
```go
Stdio: &mcp.StdioConfig{
Command: "uvx",
Args: []string{"mcp-server-time"},
Env: []string{"DEBUG=1"},
}
```
### SSE (Web clients)
```go
SSE: &mcp.SSEConfig{
BaseURL: "http://localhost:3000/sse",
}
```
