# google-vertex-tools (Google Vertex Tools)

Example configurations for testing Google Vertex AI models with function calling and tool callbacks.

You can run this example with:

```bash
npx promptfoo@latest init --example google-vertex-tools
cd google-vertex-tools
```

## Purpose

This example demonstrates how to use [Vertex AI models](https://www.promptfoo.dev/docs/providers/vertex/) with:

- Function calling and tool declarations with Gemini 3.8 Flash
- Streamed function-call arguments and callback execution with local implementations
- Different configuration approaches (YAML vs JavaScript)

## Prerequisites

1. Install the Google Auth Library:

   ```sh
   npm install google-auth-library
   ```

2. Enable the Vertex AI API in your Google Cloud project

3. Configure your Google Cloud project:

   ```sh
   gcloud config set project PROJECT_ID
   ```

4. Set up authentication using one of these methods:
   - Authenticate with your Google account:

     ```sh
     gcloud auth application-default login
     ```

   - Use a machine with an authorized service account
   - Use service account credentials file:
     1. Download your service account JSON
     2. Set the credentials path:

        ```sh
        export GOOGLE_APPLICATION_CREDENTIALS=/path/to/credentials.json
        ```

## Configurations

This example includes two different approaches:

### Basic Tool Declaration (`promptfooconfig.yaml`)

Uses external tool definitions and validates function calls without execution:

- `promptfooconfig.yaml` - YAML configuration with external tools
- `tools.json` - Function definitions for weather lookup

The basic config selects `gemini-3.8-flash` on the `global` endpoint for the target and text grader. Its semantic assertion uses Vertex `text-embedding-005`; this cloud model is separate from the native Gemini embedding namespace.

### Function Callbacks (`promptfooconfig-callback.mjs`)

Demonstrates streamed function-call arguments and actual function execution with local callbacks:

- `promptfooconfig-callback.mjs` - Portable ESM configuration with inline tools and callbacks
- Includes local function implementation for adding numbers

Callbacks execute as trusted, unsandboxed local code. Isolate runs that use untrusted models or eval content.

## Running the Examples

1. **Basic tool declaration example:**

   ```sh
   promptfoo eval -c promptfooconfig.yaml
   ```

2. **Function callback example:**

   ```sh
   promptfoo eval -c promptfooconfig-callback.mjs
   ```

3. **View results:**

   ```sh
   promptfoo view
   ```

## Expected Results

- **Basic example**: Validates that the model correctly calls the weather function with proper parameters
- **Callback example**: Assembles streamed arguments, executes the addition function, and validates the computed results

## Learn More

- [Vertex AI Provider Documentation](https://www.promptfoo.dev/docs/providers/vertex/)
- [Google Cloud Vertex AI Documentation](https://cloud.google.com/vertex-ai/docs)
- [Function Calling Documentation](https://www.promptfoo.dev/docs/providers/vertex/#function-calling)
- [promptfoo Documentation](https://www.promptfoo.dev/docs/)