ag_ui_langgraph not passing front-end tools

I'm using the AG UI Langgraph v0.0.22 library to interface with my Langgraph agent. In my code, I pass in a front-end tool from the front-end into the payload. I confirmed that the backend receives the payload correctly and the tool is in the payload. However, the tool isn't passed to the LLM call. I have two backend tools that are passed correctly.

My backend is a FastAPI Python application and I'm using LangChain / LangGraph v1. My agent is a simple agent implemented using LangChain v1's `create_agent()` feature.

In reviewing the code, I see that the `agent.py` library has a method named `prepare_regenerate_stream()` that has an unused reference to `tools`. I'm not sure if that's the issue or not as I haven't diagnosed it further yet.

Here is the frontend tool code (I took it directly from the the [AG-UI Tools documentation](https://docs.ag-ui.com/concepts/tools):

```javascript
[ {
name: "confirmAction",
description: "Ask the user to confirm a specific action before proceeding",
parameters: {
type: "object",
properties: {
action: {
type: "string",
description: "The action that needs user confirmation",
},
importance: {
type: "string",
enum: ["low", "medium", "high", "critical"],
description: "The importance level of the action",
},
},
required: ["action"],
},
} ]
```

Here is the log message in the backend showing the tool was received in the RunAgentInput:

```python
AG-UI Tools:
[Tool(
name='confirmAction',
description='Ask the user to confirm a specific action before proceeding',
parameters={'type': 'object', 'properties': {'action': {'type': 'string', 'description': 'The action that needs user confirmation'}, 'importance': {'type': 'string', 'enum': ['low', 'medium', 'high', 'critical'], 'description': 'The importance level of the action'}},
'required': ['action']})
]
```

Here's the log message from the LLM call:

```javascript
'request_data': {
'messages' : [ {
'content': '''You are a friendly assistant who can answer general questions.
Before answering, work through this ...''',
'role': 'system',
},
{
'content': 'Hello! How can I help you today?',
'role': 'assistant',
},
{
'content': 'hello',
'role': 'user',
},
],
'model': 'gpt-oss-20b',
'tools' : [ {
'type': 'function',
'function': {
'name': 'get_current_date_and_time',
'description': 'Tool to provide the current date and time in string format',
'parameters' : {
'properties' : { },
'type': 'object',
},
},
},
{
'type': 'function',
'function' : {
'name': 'get_weather_for_day',
'description': 'Tool to provide the current weather for a day',
'parameters' : {
'properties' : {
'date': {
'type': 'string',
},
},
'required' : ['date',],
'type': 'object',
},
},
},],
},
```