Toolbox-core SDK for connecting to the MCP Toolbox server and invoking tools programmatically.
---
## Overview
The `toolbox-core` package provides a Python interface to the MCP Toolbox service, enabling you to load and invoke tools from your own applications.
## Installation
```bash
pip install toolbox-core
```
{{< notice note >}}
* The primary `ToolboxClient` is asynchronous and requires using `await` for loading and invoking tools, as shown in most examples.
* Asynchronous code needs to run within an event loop (e.g., using `asyncio.run()` or in an async framework). See the [Python `asyncio` documentation](https://docs.python.org/3/library/asyncio-task.html) for more details.
* If you prefer synchronous execution, refer to the [Synchronous Usage](#synchronous-usage) section below.
{{< /notice >}}
{{< notice note>}}
The `ToolboxClient` (and its synchronous counterpart `ToolboxSyncClient`) interacts with network resources using an underlying HTTP client session. You should remember to use a context manager or explicitly call `close()` to clean up these resources. If you provide your own session, you'll need to close it in addition to calling `ToolboxClient.close()`.
{{< /notice >}}
## Quickstart
1.**Start the Toolbox Service**
- Make sure the MCP Toolbox service is running. See the [Toolbox Getting Started Guide](/getting-started/introduction/#getting-started).
2.**Minimal Example**
```python
importasyncio
fromtoolbox_coreimportToolboxClient
asyncdefmain():
# Replace with the actual URL where your Toolbox service is running
For a complete, end-to-end example including setting up the service and using an SDK, see the full tutorial: [**Toolbox Quickstart Tutorial**](https://googleapis.github.io/genai-toolbox/getting-started/local_quickstart)
{{< /notice >}}
{{< notice note>}}
If you initialize `ToolboxClient` without providing an external session and cannot use `async with`, you must explicitly close the client using `await toolbox.close()` in a `finally` block. This ensures the internally created session is closed.
```py
toolbox = ToolboxClient("http://127.0.0.1:5000")
try:
# ... use toolbox ...
finally:
await toolbox.close()
```
{{< /notice >}}
## Usage
Import and initialize a Toolbox client, pointing it to the URL of your running
Toolbox service.
```py
from toolbox_core import ToolboxClient
# Replace with your Toolbox service's URL
async with ToolboxClient("http://127.0.0.1:5000") as toolbox:
```
All interactions for loading and invoking tools happen through this client.
{{< notice note>}}
For advanced use cases, you can provide an external `aiohttp.ClientSession` during initialization (e.g., `ToolboxClient(url, session=my_session)`). If you provide your own session, you are responsible for managing its lifecycle; `ToolboxClient` *will not* close it.
{{< /notice >}}
{{< notice note>}}
Closing the `ToolboxClient` also closes the underlying network session shared by all tools loaded from that client. As a result, any tool instances you have loaded will cease to function and will raise an error if you attempt to invoke them after the client is closed.
{{< /notice >}}
## Loading Tools
You can load tools individually or in groups (toolsets) as defined in your
Toolbox service configuration. Loading a toolset is convenient when working with
multiple related functions, while loading a single tool offers more granular
control.
### Load a toolset
A toolset is a collection of related tools. You can load all tools in a toolset
or a specific one:
```py
# Load all tools
tools = await toolbox.load_toolset()
# Load a specific toolset
tools = await toolbox.load_toolset("my-toolset")
```
### Load a single tool
Loads a specific tool by its unique name. This provides fine-grained control.
```py
tool = await toolbox.load_tool("my-tool")
```
## Invoking Tools
Once loaded, tools behave like awaitable Python functions. You invoke them using
`await` and pass arguments corresponding to the parameters defined in the tool's
configuration within the Toolbox service.
```py
tool = await toolbox.load_tool("my-tool")
result = await tool("foo", bar="baz")
```
{{< notice tip>}}
For a more comprehensive guide on setting up the Toolbox service itself, which you'll need running to use this SDK, please refer to the [Toolbox Quickstart Guide](getting-started/local_quickstart).
{{< /notice >}}
## Synchronous Usage
By default, the `ToolboxClient` and the `ToolboxTool` objects it produces behave like asynchronous Python functions, requiring the use of `await`.
If your application primarily uses synchronous code, or you prefer not to manage an asyncio event loop, you can use the synchronous alternatives provided:
* `ToolboxSyncClient`: The synchronous counterpart to `ToolboxClient`.
* `ToolboxSyncTool`: The synchronous counterpart to `ToolboxTool`.
The `ToolboxSyncClient` handles communication with the Toolbox service synchronously and produces `ToolboxSyncTool` instances when you load tools. You do not use the `await` keyword when interacting with these synchronous versions.
```py
from toolbox_core import ToolboxSyncClient
with ToolboxSyncClient("http://127.0.0.1:5000") as toolbox:
weather_tool = toolbox.load_tool("get_weather")
result = weather_tool(location="Paris")
print(result)
```
{{< notice tip>}}
While synchronous invocation is available for convenience, it's generally considered best practice to use asynchronous operations (like those provided by the default `ToolboxClient` and `ToolboxTool`) for an I/O-bound task like tool invocation. Asynchronous programming allows for cooperative multitasking, often leading to better performance and resource utilization, especially in applications handling concurrent requests.
{{< /notice >}}
## Use with LangGraph
The Toolbox Core SDK integrates smoothly with frameworks like LangGraph,
allowing you to incorporate tools managed by the Toolbox service into your
agentic workflows.
{{< notice tip>}}
The loaded tools (both async `ToolboxTool` and sync `ToolboxSyncTool`) are callable and can often be used directly. However, to ensure parameter descriptions from Google-style docstrings are accurately parsed and made available to the LLM (via `bind_tools()`) and LangGraph internals, it's recommended to wrap the loaded tools using LangChain's [`StructuredTool`](https://python.langchain.com/api_reference/core/tools/langchain_core.tools.structured.StructuredTool.html).
{{< /notice >}}
Here's a conceptual example adapting the [official LangGraph tool calling
1. **Configure Permissions**: [Grant](https://cloud.google.com/run/docs/securing/managing-access#service-add-principals) the `roles/run.invoker` IAM role on the Cloud
Run service to the principal. This could be your `user account email` or a
**Always use HTTPS** to connect your application with the Toolbox service, especially in **production environments** or whenever the communication involves **sensitive data** (including scenarios where tools require authentication tokens). Using plain HTTP lacks encryption and exposes your application and data to significant security risks, such as eavesdropping and tampering.
{{</notice>}}
Tools can be configured within the Toolbox service to require authentication,
ensuring only authorized users or applications can invoke them, especially when
accessing sensitive data.
### When is Authentication Needed?
Authentication is configured per-tool within the Toolbox service itself. If a
tool you intend to use is marked as requiring authentication in the service, you
must configure the SDK client to provide the necessary credentials (currently
Oauth2 tokens) when invoking that specific tool.
### Supported Authentication Mechanisms
The Toolbox service enables secure tool usage through **Authenticated Parameters**. For detailed information on how these mechanisms work within the Toolbox service and how to configure them, please refer to [Authenticated Parameters](resources/tools/#authenticated-parameters)
### Step 1: Configure Tools in Toolbox Service
First, ensure the target tool(s) are configured correctly in the Toolbox service
to require authentication. Refer to the [Authenticated Parameters](https://googleapis.github.io/genai-toolbox/resources/tools/#authenticated-parameters)
for instructions.
### Step 2: Configure SDK Client
Your application needs a way to obtain the required Oauth2 token for the
authenticated user. The SDK requires you to provide a function capable of
retrieving this token *when the tool is invoked*.
#### Provide an ID Token Retriever Function
You must provide the SDK with a function (sync or async) that returns the
necessary token when called. The implementation depends on your application's
authentication flow (e.g., retrieving a stored token, initiating an OAuth flow).
{{< notice info>}}
The name used when registering the getter function with the SDK (e.g.,`"my_api_token"`) must exactly match the `name` of the corresponding `authServices` defined in the tool's configuration within the Toolbox service.
{{</notice>}}
```py
async def get_auth_token():
# ... Logic to retrieve ID token (e.g., from local storage, OAuth flow)
# This example just returns a placeholder. Replace with your actual token retrieval.
return "YOUR_ID_TOKEN" # Placeholder
```
{{< notice tip>}}
Your token retriever function is invoked every time an authenticated parameter requires a token for a tool call. Consider implementing caching logic within this function to avoid redundant token fetching or generation, especially for tokens with longer validity periods or if the retrieval process is resource-intensive.
{{</notice>}}
#### Option A: Add Authentication to a Loaded Tool
You can add the token retriever function to a tool object *after* it has been
loaded. This modifies the specific tool instance.
```py
async with ToolboxClient("http://127.0.0.1:5000") as toolbox:
tool = await toolbox.load_tool("my-tool")
auth_tool = tool.add_auth_token_getter("my_auth", get_auth_token) # Single token
# OR
multi_auth_tool = tool.add_auth_token_getters({
"my_auth_1": get_auth_token_1,
"my_auth_2": get_auth_token_2,
}) # Multiple tokens
```
#### Option B: Add Authentication While Loading Tools
You can provide the token retriever(s) directly during the `load_tool` or
`load_toolset` calls. This applies the authentication configuration only to the
tools loaded in that specific call, without modifying the original tool objects
An auth token getter for a specific name (e.g., “GOOGLE_ID”) will replace any client header with the same name followed by “_token” (e.g., “GOOGLE_ID_token”).
{{</notice>}}
## Binding Parameter Values
The SDK allows you to pre-set, or "bind", values for specific tool parameters
before the tool is invoked or even passed to an LLM. These bound values are
fixed and will not be requested or modified by the LLM during tool use.
### Why Bind Parameters?
- **Protecting sensitive information:** API keys, secrets, etc.
- **Enforcing consistency:** Ensuring specific values for certain parameters.
- **Pre-filling known data:** Providing defaults or context.
{{< notice info >}}
The parameter names used for binding (e.g., "api_key") must exactly match the parameter names defined in the tool’s configuration within the Toolbox service.
{{</notice>}}
{{< notice >}}
You do not need to modify the tool’s configuration in the Toolbox service to bind parameter values using the SDK.
{{</notice>}}
### Option A: Binding Parameters to a Loaded Tool
Bind values to a tool object *after* it has been loaded. This modifies the
specific tool instance.
```py
async with ToolboxClient("http://127.0.0.1:5000") as toolbox:
tool = await toolbox.load_tool("my-tool")
bound_tool = tool.bind_param("param", "value")
# OR
bound_tool = tool.bind_params({"param": "value"})
```
### Option B: Binding Parameters While Loading Tools
Specify bound parameters directly when loading tools. This applies the binding
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