# LLMonitorCallbackHandler

> **Class** in `langchain_community`

📖 [View in docs](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler)

Callback Handler for LLMonitor`.

#### Parameters:
    - `app_id`: The app id of the app you want to report to. Defaults to
    `None`, which means that `LLMONITOR_APP_ID` will be used.
    - `api_url`: The url of the LLMonitor API. Defaults to `None`,
    which means that either `LLMONITOR_API_URL` environment variable
    or `https://app.llmonitor.com` will be used.

#### Raises:
    - `ValueError`: if `app_id` is not provided either as an
    argument or as an environment variable.
    - `ConnectionError`: if the connection to the API fails.

#### Example:
```python
from langchain_community.llms import OpenAI
from langchain_community.callbacks import LLMonitorCallbackHandler

llmonitor_callback = LLMonitorCallbackHandler()
llm = OpenAI(callbacks=[llmonitor_callback],
             metadata={"userId": "user-123"})
llm.invoke("Hello, how are you?")
```

## Signature

```python
LLMonitorCallbackHandler(
    self,
    app_id: Union[str, None] = None,
    api_url: Union[str, None] = None,
    verbose: bool = False,
)
```

## Extends

- `BaseCallbackHandler`

## Constructors

```python
__init__(
    self,
    app_id: Union[str, None] = None,
    api_url: Union[str, None] = None,
    verbose: bool = False,
) -> None
```

| Name | Type |
|------|------|
| `app_id` | `Union[str, None]` |
| `api_url` | `Union[str, None]` |
| `verbose` | `bool` |


## Methods

- [`on_llm_start()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_llm_start)
- [`on_chat_model_start()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_chat_model_start)
- [`on_llm_end()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_llm_end)
- [`on_tool_start()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_tool_start)
- [`on_tool_end()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_tool_end)
- [`on_chain_start()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_chain_start)
- [`on_chain_end()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_chain_end)
- [`on_agent_action()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_agent_action)
- [`on_agent_finish()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_agent_finish)
- [`on_chain_error()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_chain_error)
- [`on_tool_error()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_tool_error)
- [`on_llm_error()`](https://reference.langchain.com/python/langchain-community/callbacks/llmonitor_callback/LLMonitorCallbackHandler/on_llm_error)

---

[View source on GitHub](https://github.com/langchain-ai/langchain-community/blob/d5ea8358933260ad48dd31f7f8076555c7b4885a/libs/community/langchain_community/callbacks/llmonitor_callback.py#L183)