genai-toolbox/docs/en/getting-started/local_quickstart_go.md

---
title: "Go Quickstart (Local)"
type: docs
weight: 4
description: >
  How to get started running Toolbox locally with [Go](https://github.com/googleapis/mcp-toolbox-sdk-go), PostgreSQL, and orchestration frameworks such as [LangChain Go](https://tmc.github.io/langchaingo/docs/), [GenkitGo](https://genkit.dev/go/docs/get-started-go/), [Go GenAI](https://github.com/googleapis/go-genai) and [OpenAI Go](https://github.com/openai/openai-go).
---

## Before you begin

This guide assumes you have already done the following:

1. Installed [Go (v1.24.2 or higher)].
1. Installed [PostgreSQL 16+ and the `psql` client][install-postgres].

### Cloud Setup (Optional)

If you plan to use **Google Cloud’s Vertex AI** with your agent (e.g., using
Gemini or PaLM models), follow these one-time setup steps:

1. [Install the Google Cloud CLI]
1. [Set up Application Default Credentials (ADC)]
1. Set your project and enable Vertex AI

    ```bash
    gcloud config set project YOUR_PROJECT_ID
    gcloud services enable aiplatform.googleapis.com
    ```

[Go (v1.24.2 or higher)]: https://go.dev/doc/install
[install-postgres]: https://www.postgresql.org/download/
[Install the Google Cloud CLI]: https://cloud.google.com/sdk/docs/install
[Set up Application Default Credentials (ADC)]:
    https://cloud.google.com/docs/authentication/set-up-adc-local-dev-environment

## Step 1: Set up your database

In this section, we will create a database, insert some data that needs to be
accessed by our agent, and create a database user for Toolbox to connect with.

1. Connect to postgres using the `psql` command:

    ```bash
    psql -h 127.0.0.1 -U postgres
    ```

    Here, `postgres` denotes the default postgres superuser.

    {{< notice info >}}

#### **Having trouble connecting?**

* **Password Prompt:** If you are prompted for a password for the `postgres`
  user and do not know it (or a blank password doesn't work), your PostgreSQL
  installation might require a password or a different authentication method.
* **`FATAL: role "postgres" does not exist`:** This error means the default
  `postgres` superuser role isn't available under that name on your system.
* **`Connection refused`:** Ensure your PostgreSQL server is actually running.
  You can typically check with `sudo systemctl status postgresql` and start it
  with `sudo systemctl start postgresql` on Linux systems.

<br/>

#### **Common Solution**

For password issues or if the `postgres` role seems inaccessible directly, try
switching to the `postgres` operating system user first. This user often has
permission to connect without a password for local connections (this is called
peer authentication).

```bash
sudo -i -u postgres
psql -h 127.0.0.1
```

Once you are in the `psql` shell using this method, you can proceed with the
database creation steps below. Afterwards, type `\q` to exit `psql`, and then
`exit` to return to your normal user shell.

If desired, once connected to `psql` as the `postgres` OS user, you can set a
password for the `postgres` *database* user using: `ALTER USER postgres WITH
PASSWORD 'your_chosen_password';`. This would allow direct connection with `-U
postgres` and a password next time.
    {{< /notice >}}

1. Create a new database and a new user:

    {{< notice tip >}}
  For a real application, it's best to follow the principle of least permission
  and only grant the privileges your application needs.
    {{< /notice >}}

    ```sql
      CREATE USER toolbox_user WITH PASSWORD 'my-password';

      CREATE DATABASE toolbox_db;
      GRANT ALL PRIVILEGES ON DATABASE toolbox_db TO toolbox_user;

      ALTER DATABASE toolbox_db OWNER TO toolbox_user;
    ```

1. End the database session:

    ```bash
    \q
    ```

    (If you used `sudo -i -u postgres` and then `psql`, remember you might also
    need to type `exit` after `\q` to leave the `postgres` user's shell
    session.)

1. Connect to your database with your new user:

    ```bash
    psql -h 127.0.0.1 -U toolbox_user -d toolbox_db
    ```

1. Create a table using the following command:

    ```sql
    CREATE TABLE hotels(
      id            INTEGER NOT NULL PRIMARY KEY,
      name          VARCHAR NOT NULL,
      location      VARCHAR NOT NULL,
      price_tier    VARCHAR NOT NULL,
      checkin_date  DATE    NOT NULL,
      checkout_date DATE    NOT NULL,
      booked        BIT     NOT NULL
    );
    ```

1. Insert data into the table.

    ```sql
    INSERT INTO hotels(id, name, location, price_tier, checkin_date, checkout_date, booked)
    VALUES
      (1, 'Hilton Basel', 'Basel', 'Luxury', '2024-04-22', '2024-04-20', B'0'),
      (2, 'Marriott Zurich', 'Zurich', 'Upscale', '2024-04-14', '2024-04-21', B'0'),
      (3, 'Hyatt Regency Basel', 'Basel', 'Upper Upscale', '2024-04-02', '2024-04-20', B'0'),
      (4, 'Radisson Blu Lucerne', 'Lucerne', 'Midscale', '2024-04-24', '2024-04-05', B'0'),
      (5, 'Best Western Bern', 'Bern', 'Upper Midscale', '2024-04-23', '2024-04-01', B'0'),
      (6, 'InterContinental Geneva', 'Geneva', 'Luxury', '2024-04-23', '2024-04-28', B'0'),
      (7, 'Sheraton Zurich', 'Zurich', 'Upper Upscale', '2024-04-27', '2024-04-02', B'0'),
      (8, 'Holiday Inn Basel', 'Basel', 'Upper Midscale', '2024-04-24', '2024-04-09', B'0'),
      (9, 'Courtyard Zurich', 'Zurich', 'Upscale', '2024-04-03', '2024-04-13', B'0'),
      (10, 'Comfort Inn Bern', 'Bern', 'Midscale', '2024-04-04', '2024-04-16', B'0');
    ```

1. End the database session:

    ```bash
    \q
    ```

## Step 2: Install and configure Toolbox

In this section, we will download Toolbox, configure our tools in a
`tools.yaml`, and then run the Toolbox server.

1. Download the latest version of Toolbox as a binary:

    {{< notice tip >}}
  Select the
  [correct binary](https://github.com/googleapis/genai-toolbox/releases)
  corresponding to your OS and CPU architecture.
    {{< /notice >}}
    <!-- {x-release-please-start-version} -->
    ```bash
    export OS="linux/amd64" # one of linux/amd64, darwin/arm64, darwin/amd64, or windows/amd64
    curl -O https://storage.googleapis.com/genai-toolbox/v0.11.0/$OS/toolbox
    ```
    <!-- {x-release-please-end} -->

1. Make the binary executable:

    ```bash
    chmod +x toolbox
    ```

1. Write the following into a `tools.yaml` file. Be sure to update any fields
   such as `user`, `password`, or `database` that you may have customized in the
   previous step.

    {{< notice tip >}}
  In practice, use environment variable replacement with the format ${ENV_NAME}
  instead of hardcoding your secrets into the configuration file.
    {{< /notice >}}

    ```yaml
    sources:
      my-pg-source:
        kind: postgres
        host: 127.0.0.1
        port: 5432
        database: toolbox_db
        user: ${USER_NAME}
        password: ${PASSWORD}
    tools:
      search-hotels-by-name:
        kind: postgres-sql
        source: my-pg-source
        description: Search for hotels based on name.
        parameters:
          - name: name
            type: string
            description: The name of the hotel.
        statement: SELECT * FROM hotels WHERE name ILIKE '%' || $1 || '%';
      search-hotels-by-location:
        kind: postgres-sql
        source: my-pg-source
        description: Search for hotels based on location.
        parameters:
          - name: location
            type: string
            description: The location of the hotel.
        statement: SELECT * FROM hotels WHERE location ILIKE '%' || $1 || '%';
      book-hotel:
        kind: postgres-sql
        source: my-pg-source
        description: >-
           Book a hotel by its ID. If the hotel is successfully booked, returns a NULL, raises an error if not.
        parameters:
          - name: hotel_id
            type: string
            description: The ID of the hotel to book.
        statement: UPDATE hotels SET booked = B'1' WHERE id = $1;
      update-hotel:
        kind: postgres-sql
        source: my-pg-source
        description: >-
          Update a hotel's check-in and check-out dates by its ID. Returns a message
          indicating  whether the hotel was successfully updated or not.
        parameters:
          - name: hotel_id
            type: string
            description: The ID of the hotel to update.
          - name: checkin_date
            type: string
            description: The new check-in date of the hotel.
          - name: checkout_date
            type: string
            description: The new check-out date of the hotel.
        statement: >-
          UPDATE hotels SET checkin_date = CAST($2 as date), checkout_date = CAST($3
          as date) WHERE id = $1;
      cancel-hotel:
        kind: postgres-sql
        source: my-pg-source
        description: Cancel a hotel by its ID.
        parameters:
          - name: hotel_id
            type: string
            description: The ID of the hotel to cancel.
        statement: UPDATE hotels SET booked = B'0' WHERE id = $1;
   toolsets:
      my-toolset:
        - search-hotels-by-name
        - search-hotels-by-location
        - book-hotel
        - update-hotel
        - cancel-hotel
    ```

    For more info on tools, check out the `Resources` section of the docs.

1. Run the Toolbox server, pointing to the `tools.yaml` file created earlier:

    ```bash
    ./toolbox --tools-file "tools.yaml"
    ```

  {{< notice note >}}
    Toolbox enables dynamic reloading by default. To disable, use the
    `--disable-reload` flag.
  {{< /notice >}}

## Step 3: Connect your agent to Toolbox

In this section, we will write and run an agent that will load the Tools
from Toolbox.

1. Initialize a go module:

    ```bash
    go mod init main
    ```

1. In a new terminal, install the
   [SDK](https://pkg.go.dev/github.com/googleapis/mcp-toolbox-sdk-go).

    ```bash
    go get github.com/googleapis/mcp-toolbox-sdk-go
    ```

1. Create a new file named `hotelagent.go` and copy the following code to create
   an agent:

    {{< tabpane persist=header >}}
{{< tab header="LangChain Go" lang="go" >}}

package main

import (
	"context"
	"encoding/json"
	"fmt"
	"log"
	"os"

	"github.com/googleapis/mcp-toolbox-sdk-go/core"
	"github.com/tmc/langchaingo/llms"
	"github.com/tmc/langchaingo/llms/googleai"
)

// ConvertToLangchainTool converts a generic core.ToolboxTool into a LangChainGo llms.Tool.
func ConvertToLangchainTool(toolboxTool *core.ToolboxTool) llms.Tool {

	// Fetch the tool's input schema
	inputschema, err := toolboxTool.InputSchema()
	if err != nil {
		return llms.Tool{}
	}

	var paramsSchema map[string]any
	_ = json.Unmarshal(inputschema, &paramsSchema)

	// Convert into LangChain's llms.Tool
	return llms.Tool{
		Type: "function",
		Function: &llms.FunctionDefinition{
			Name:        toolboxTool.Name(),
			Description: toolboxTool.Description(),
			Parameters:  paramsSchema,
		},
	}
}

const systemPrompt = `
You're a helpful hotel assistant. You handle hotel searching, booking, and
cancellations. When the user searches for a hotel, mention its name, id,
location and price tier. Always mention hotel ids while performing any
searches. This is very important for any operations. For any bookings or
cancellations, please provide the appropriate confirmation. Be sure to
update checkin or checkout dates if mentioned by the user.
Don't ask for confirmations from the user.
`

var queries = []string{
	"Find hotels in Basel with Basel in its name.",
	"Can you book the hotel Hilton Basel for me?",
	"Oh wait, this is too expensive. Please cancel it.",
	"Please book the Hyatt Regency instead.",
	"My check in dates would be from April 10, 2024 to April 19, 2024.",
}

func main() {
	genaiKey := os.Getenv("GOOGLE_API_KEY")
	toolboxURL := "http://localhost:5000"
	ctx := context.Background()

	// Initialize the Google AI client (LLM).
	llm, err := googleai.New(ctx, googleai.WithAPIKey(genaiKey), googleai.WithDefaultModel("gemini-1.5-flash"))
	if err != nil {
		log.Fatalf("Failed to create Google AI client: %v", err)
	}

	// Initialize the MCP Toolbox client.
	toolboxClient, err := core.NewToolboxClient(toolboxURL)
	if err != nil {
		log.Fatalf("Failed to create Toolbox client: %v", err)
	}

	// Load the tool using the MCP Toolbox SDK.
	tools, err := toolboxClient.LoadToolset("my-toolset", ctx)
	if err != nil {
		log.Fatalf("Failed to load tools: %v\nMake sure your Toolbox server is running and the tool is configured.", err)
	}

	toolsMap := make(map[string]*core.ToolboxTool, len(tools))

	langchainTools := make([]llms.Tool, len(tools))
	// Convert the loaded ToolboxTools into the format LangChainGo requires.
	for i, tool := range tools {
		langchainTools[i] = ConvertToLangchainTool(tool)
		toolsMap[tool.Name()] = tool
	}

	// Start the conversation history.
	messageHistory := []llms.MessageContent{
		llms.TextParts(llms.ChatMessageTypeSystem, systemPrompt),
	}

	for _, query := range queries {
		messageHistory = append(messageHistory, llms.TextParts(llms.ChatMessageTypeHuman, query))

		// Make the first call to the LLM, making it aware of the tool.
		resp, err := llm.GenerateContent(ctx, messageHistory, llms.WithTools(langchainTools))
		if err != nil {
			log.Fatalf("LLM call failed: %v", err)
		}
		respChoice := resp.Choices[0]

		assistantResponse := llms.TextParts(llms.ChatMessageTypeAI, respChoice.Content)
		for _, tc := range respChoice.ToolCalls {
			assistantResponse.Parts = append(assistantResponse.Parts, tc)
		}
		messageHistory = append(messageHistory, assistantResponse)

		// Process each tool call requested by the model.
		for _, tc := range respChoice.ToolCalls {
			toolName := tc.FunctionCall.Name
			tool := toolsMap[toolName]
			var args map[string]any
			if err := json.Unmarshal([]byte(tc.FunctionCall.Arguments), &args); err != nil {
				log.Fatalf("Failed to unmarshal arguments for tool '%s': %v", toolName, err)
			}
			toolResult, err := tool.Invoke(ctx, args)
			if err != nil {
				log.Fatalf("Failed to execute tool '%s': %v", toolName, err)
			}
			if toolResult == "" || toolResult == nil {
				toolResult = "Operation completed successfully with no specific return value."
			}

			// Create the tool call response message and add it to the history.
			toolResponse := llms.MessageContent{
				Role: llms.ChatMessageTypeTool,
				Parts: []llms.ContentPart{
					llms.ToolCallResponse{
						Name:    toolName,
						Content: fmt.Sprintf("%v", toolResult),
					},
				},
			}
			messageHistory = append(messageHistory, toolResponse)
		}
		finalResp, err := llm.GenerateContent(ctx, messageHistory)
		if err != nil {
			log.Fatalf("Final LLM call failed after tool execution: %v", err)
		}

		// Add the final textual response from the LLM to the history
		messageHistory = append(messageHistory, llms.TextParts(llms.ChatMessageTypeAI, finalResp.Choices[0].Content))

		fmt.Println(finalResp.Choices[0].Content)

	}

}

{{< /tab >}}

{{< tab header="Genkit Go" lang="go" >}}

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/googleapis/mcp-toolbox-sdk-go/core"
	"github.com/googleapis/mcp-toolbox-sdk-go/tbgenkit"

	"github.com/firebase/genkit/go/ai"
	"github.com/firebase/genkit/go/genkit"
	"github.com/firebase/genkit/go/plugins/googlegenai"
)

const systemPrompt = `
You're a helpful hotel assistant. You handle hotel searching, booking, and
cancellations. When the user searches for a hotel, mention its name, id,
location and price tier. Always mention hotel ids while performing any
searches. This is very important for any operations. For any bookings or
cancellations, please provide the appropriate confirmation. Be sure to
update checkin or checkout dates if mentioned by the user.
Don't ask for confirmations from the user.
`

var queries = []string{
	"Find hotels in Basel with Basel in its name.",
	"Can you book the hotel Hilton Basel for me?",
	"Oh wait, this is too expensive. Please cancel it and book the Hyatt Regency instead.",
	"My check in dates would be from April 10, 2024 to April 19, 2024.",
}

func main() {
	ctx := context.Background()

	// Create Toolbox Client
	toolboxClient, err := core.NewToolboxClient("http://127.0.0.1:5000")
	if err != nil {
		log.Fatalf("Failed to create Toolbox client: %v", err)
	}

	// Load the tools using the MCP Toolbox SDK.
	tools, err := toolboxClient.LoadToolset("my-toolset", ctx)
	if err != nil {
		log.Fatalf("Failed to load tools: %v\nMake sure your Toolbox server is running and the tool is configured.", err)
	}

	// Initialize Genkit
	g, err := genkit.Init(ctx,
		genkit.WithPlugins(&googlegenai.GoogleAI{}),
		genkit.WithDefaultModel("googleai/gemini-1.5-flash"),
	)
	if err != nil {
		log.Fatalf("Failed to init genkit: %v\n", err)
	}

	// Create a conversation history
	conversationHistory := []*ai.Message{
		ai.NewSystemTextMessage(systemPrompt),
	}

	// Convert your tool to a Genkit tool.
	genkitTools := make([]ai.Tool, len(tools))
	for i, tool := range tools {
		newTool, err := tbgenkit.ToGenkitTool(tool, g)
		if err != nil {
			log.Fatalf("Failed to convert tool: %v\n", err)
		}
		genkitTools[i] = newTool
	}

	toolRefs := make([]ai.ToolRef, len(genkitTools))

	for i, tool := range genkitTools {
		toolRefs[i] = tool
	}

	for _, query := range queries {
		conversationHistory = append(conversationHistory, ai.NewUserTextMessage(query))
		response, err := genkit.Generate(ctx, g,
			ai.WithMessages(conversationHistory...),
			ai.WithTools(toolRefs...),
			ai.WithReturnToolRequests(true),
		)

		if err != nil {
			log.Fatalf("%v\n", err)
		}
		conversationHistory = append(conversationHistory, response.Message)

		parts := []*ai.Part{}

		for _, req := range response.ToolRequests() {
			tool := genkit.LookupTool(g, req.Name)
			if tool == nil {
				log.Fatalf("tool %q not found", req.Name)
			}

			output, err := tool.RunRaw(ctx, req.Input)
			if err != nil {
				log.Fatalf("tool %q execution failed: %v", tool.Name(), err)
			}

			parts = append(parts,
				ai.NewToolResponsePart(&ai.ToolResponse{
					Name:   req.Name,
					Ref:    req.Ref,
					Output: output,
				}))

		}

		if len(parts) > 0 {
			resp, err := genkit.Generate(ctx, g,
				ai.WithMessages(append(response.History(), ai.NewMessage(ai.RoleTool, nil, parts...))...),
				ai.WithTools(toolRefs...),
			)
			if err != nil {
				log.Fatal(err)
			}
			fmt.Println("\n", resp.Text())
			conversationHistory = append(conversationHistory, resp.Message)
		} else {
			fmt.Println("\n", response.Text())
		}

	}

}

{{< /tab >}}

{{< tab header="Go GenAI" lang="go" >}}

package main

import (
	"context"
	"encoding/json"
	"fmt"
	"log"
	"os"

	"github.com/googleapis/mcp-toolbox-sdk-go/core"
	"google.golang.org/genai"
)

// ConvertToGenaiTool translates a ToolboxTool into the genai.FunctionDeclaration format.
func ConvertToGenaiTool(toolboxTool *core.ToolboxTool) *genai.Tool {

	inputschema, err := toolboxTool.InputSchema()
	if err != nil {
		return &genai.Tool{}
	}

	var paramsSchema *genai.Schema
	_ = json.Unmarshal(inputschema, &paramsSchema)
	// First, create the function declaration.
	funcDeclaration := &genai.FunctionDeclaration{
		Name:        toolboxTool.Name(),
		Description: toolboxTool.Description(),
		Parameters:  paramsSchema,
	}

	// Then, wrap the function declaration in a genai.Tool struct.
	return &genai.Tool{
		FunctionDeclarations: []*genai.FunctionDeclaration{funcDeclaration},
	}
}

func printResponse(resp *genai.GenerateContentResponse) {
	for _, cand := range resp.Candidates {
		if cand.Content != nil {
			for _, part := range cand.Content.Parts {
				fmt.Println(part.Text)
			}
		}
	}
}

const systemPrompt = `
You're a helpful hotel assistant. You handle hotel searching, booking, and
cancellations. When the user searches for a hotel, mention its name, id,
location and price tier. Always mention hotel ids while performing any
searches. This is very important for any operations. For any bookings or
cancellations, please provide the appropriate confirmation. Be sure to
update checkin or checkout dates if mentioned by the user.
Don't ask for confirmations from the user.
`

var queries = []string{
	"Find hotels in Basel with Basel in its name.",
	"Can you book the hotel Hilton Basel for me?",
	"Oh wait, this is too expensive. Please cancel it.",
	"Please book the Hyatt Regency instead.",
	"My check in dates would be from April 10, 2024 to April 19, 2024.",
}

func main() {
	// Setup
	ctx := context.Background()
	apiKey := os.Getenv("GOOGLE_API_KEY")
	toolboxURL := "http://localhost:5000"

	// Initialize the Google GenAI client using the explicit ClientConfig.
	client, err := genai.NewClient(ctx, &genai.ClientConfig{
		APIKey: apiKey,
	})
	if err != nil {
		log.Fatalf("Failed to create Google GenAI client: %v", err)
	}

	// Initialize the MCP Toolbox client.
	toolboxClient, err := core.NewToolboxClient(toolboxURL)
	if err != nil {
		log.Fatalf("Failed to create Toolbox client: %v", err)
	}

	// Load the tool using the MCP Toolbox SDK.
	tools, err := toolboxClient.LoadToolset("my-toolset", ctx)
	if err != nil {
		log.Fatalf("Failed to load tools: %v\nMake sure your Toolbox server is running and the tool is configured.", err)
	}

	genAITools := make([]*genai.Tool, len(tools))
	toolsMap := make(map[string]*core.ToolboxTool, len(tools))

	for i, tool := range tools {
		genAITools[i] = ConvertToGenaiTool(tool)
		toolsMap[tool.Name()] = tool
	}

	// Set up the generative model with the available tool.
	modelName := "gemini-2.0-flash"

	// Create the initial content prompt for the model.
	messageHistory := []*genai.Content{
		genai.NewContentFromText(systemPrompt, genai.RoleUser),
	}
	config := &genai.GenerateContentConfig{
		Tools: genAITools,
		ToolConfig: &genai.ToolConfig{
			FunctionCallingConfig: &genai.FunctionCallingConfig{
				Mode: genai.FunctionCallingConfigModeAny,
			},
		},
	}

	for _, query := range queries {

		messageHistory = append(messageHistory, genai.NewContentFromText(query, genai.RoleUser))

		genContentResp, err := client.Models.GenerateContent(ctx, modelName, messageHistory, config)
		if err != nil {
			log.Fatalf("LLM call failed for query '%s': %v", query, err)
		}

		if len(genContentResp.Candidates) > 0 && genContentResp.Candidates[0].Content != nil {
			messageHistory = append(messageHistory, genContentResp.Candidates[0].Content)
		}

		functionCalls := genContentResp.FunctionCalls()

		toolResponseParts := []*genai.Part{}

		for _, fc := range functionCalls {

			toolToInvoke, found := toolsMap[fc.Name]
			if !found {
				log.Fatalf("Tool '%s' not found in loaded tools map. Check toolset configuration.", fc.Name)
			}

			toolResult, invokeErr := toolToInvoke.Invoke(ctx, fc.Args)
			if invokeErr != nil {
				log.Fatalf("Failed to execute tool '%s': %v", fc.Name, invokeErr)
			}

			// Enhanced Tool Result Handling (retained to prevent nil issues)
			toolResultString := ""
			if toolResult != nil {
				jsonBytes, marshalErr := json.Marshal(toolResult)
				if marshalErr == nil {
					toolResultString = string(jsonBytes)
				} else {
					toolResultString = fmt.Sprintf("%v", toolResult)
				}
			}

			responseMap := map[string]any{"result": toolResultString}

			toolResponseParts = append(toolResponseParts, genai.NewPartFromFunctionResponse(fc.Name, responseMap))
		}
		// Add all accumulated tool responses for this turn to the message history.
		toolResponseContent := genai.NewContentFromParts(toolResponseParts, "function")
		messageHistory = append(messageHistory, toolResponseContent)

		finalResponse, err := client.Models.GenerateContent(ctx, modelName, messageHistory, &genai.GenerateContentConfig{})
		if err != nil {
			log.Fatalf("Error calling GenerateContent (with function result): %v", err)
		}

		printResponse(finalResponse)
		// Add the final textual response from the LLM to the history
		if len(finalResponse.Candidates) > 0 && finalResponse.Candidates[0].Content != nil {
			messageHistory = append(messageHistory, finalResponse.Candidates[0].Content)
		}
	}
}

{{< /tab >}}

{{< tab header="OpenAI Go" lang="go" >}}

package main

import (
	"context"
	"encoding/json"
	"log"

	"github.com/googleapis/mcp-toolbox-sdk-go/core"
	openai "github.com/openai/openai-go"
)

// ConvertToOpenAITool converts a ToolboxTool into the go-openai library's Tool format.
func ConvertToOpenAITool(toolboxTool *core.ToolboxTool) openai.ChatCompletionToolParam {
	// Get the input schema
	jsonSchemaBytes, err := toolboxTool.InputSchema()
	if err != nil {
		return openai.ChatCompletionToolParam{}
	}

	// Unmarshal the JSON bytes into FunctionParameters
	var paramsSchema openai.FunctionParameters
	if err := json.Unmarshal(jsonSchemaBytes, &paramsSchema); err != nil {
		return openai.ChatCompletionToolParam{}
	}

	// Create and return the final tool parameter struct.
	return openai.ChatCompletionToolParam{
		Function: openai.FunctionDefinitionParam{
			Name:        toolboxTool.Name(),
			Description: openai.String(toolboxTool.Description()),
			Parameters:  paramsSchema,
		},
	}
}

const systemPrompt = `
You're a helpful hotel assistant. You handle hotel searching, booking, and
cancellations. When the user searches for a hotel, mention its name, id,
location and price tier. Always mention hotel ids while performing any
searches. This is very important for any operations. For any bookings or
cancellations, please provide the appropriate confirmation. Be sure to
update checkin or checkout dates if mentioned by the user.
Don't ask for confirmations from the user.
`

var queries = []string{
	"Find hotels in Basel with Basel in its name.",
	"Can you book the hotel Hilton Basel for me?",
	"Oh wait, this is too expensive. Please cancel it and book the Hyatt Regency instead.",
	"My check in dates would be from April 10, 2024 to April 19, 2024.",
}

func main() {
	// Setup
	ctx := context.Background()
	toolboxURL := "http://localhost:5000"
	openAIClient := openai.NewClient()

	// Initialize the MCP Toolbox client.
	toolboxClient, err := core.NewToolboxClient(toolboxURL)
	if err != nil {
		log.Fatalf("Failed to create Toolbox client: %v", err)
	}

	// Load the tools using the MCP Toolbox SDK.
	tools, err := toolboxClient.LoadToolset("my-toolset", ctx)
	if err != nil {
		log.Fatalf("Failed to load tool : %v\nMake sure your Toolbox server is running and the tool is configured.", err)
	}

	openAITools := make([]openai.ChatCompletionToolParam, len(tools))
	toolsMap := make(map[string]*core.ToolboxTool, len(tools))

	for i, tool := range tools {
		// Convert the Toolbox tool into the openAI FunctionDeclaration format.
		openAITools[i] = ConvertToOpenAITool(tool)
		// Add tool to a map for lookup later
		toolsMap[tool.Name()] = tool

	}

	params := openai.ChatCompletionNewParams{
		Messages: []openai.ChatCompletionMessageParamUnion{
			openai.SystemMessage(systemPrompt),
		},
		Tools: openAITools,
		Seed:  openai.Int(0),
		Model: openai.ChatModelGPT4o,
	}

	for _, query := range queries {

		params.Messages = append(params.Messages, openai.UserMessage(query))

		// Make initial chat completion request
		completion, err := openAIClient.Chat.Completions.New(ctx, params)
		if err != nil {
			panic(err)
		}

		toolCalls := completion.Choices[0].Message.ToolCalls

		// Return early if there are no tool calls
		if len(toolCalls) == 0 {
			log.Println("No function call")
		}

		// If there is a was a function call, continue the conversation
		params.Messages = append(params.Messages, completion.Choices[0].Message.ToParam())
		for _, toolCall := range toolCalls {

			toolName := toolCall.Function.Name
			toolToInvoke := toolsMap[toolName]

			var args map[string]any
			err := json.Unmarshal([]byte(toolCall.Function.Arguments), &args)
			if err != nil {
				panic(err)
			}

			result, err := toolToInvoke.Invoke(ctx, args)
			if err != nil {
				log.Fatal("Could not invoke tool", err)
			}

			params.Messages = append(params.Messages, openai.ToolMessage(result.(string), toolCall.ID))
		}

		completion, err = openAIClient.Chat.Completions.New(ctx, params)
		if err != nil {
			panic(err)
		}

		params.Messages = append(params.Messages, openai.AssistantMessage(query))

		println("\n", completion.Choices[0].Message.Content)

	}

}

{{< /tab >}}
{{< /tabpane >}}

1. Ensure all dependencies are installed:

    ```sh
    go mod tidy
    ```

1. Run your agent, and observe the results:

    ```sh
    go run hotelagent.go
    ```

{{< notice info >}}
For more information, visit the [Go SDK
repo](https://github.com/googleapis/mcp-toolbox-sdk-go).
{{</ notice >}}