Openai compatible lm invoker
Defines a module to interact with endpoints compatible with OpenAI's chat completion API contract.
References
[1] https://platform.openai.com/docs/api-reference/chat
OpenAICompatibleLMInvoker(model_name, base_url, api_key=None, model_kwargs=None, default_hyperparameters=None, tools=None, response_schema=None, output_analytics=False, retry_config=None, reasoning_effort=None, bind_tools_params=None, with_structured_output_params=None)
Bases: BaseLMInvoker
A language model invoker to interact with endpoints compatible with OpenAI's chat completion API contract.
Attributes:
Name | Type | Description |
---|---|---|
model_id |
str
|
The model ID of the language model. |
model_provider |
str
|
The provider of the language model. |
model_name |
str
|
The name of the language model. |
client |
AsyncOpenAI
|
The OpenAI client instance. |
default_hyperparameters |
dict[str, Any]
|
Default hyperparameters for invoking the model. |
tools |
list[Any]
|
The list of tools provided to the model to enable tool calling. |
response_schema |
ResponseSchema | None
|
The schema of the response. If provided, the model will output a structured response as defined by the schema. Supports both Pydantic BaseModel and JSON schema dictionary. |
output_analytics |
bool
|
Whether to output the invocation analytics. |
retry_config |
RetryConfig | None
|
The retry configuration for the language model. |
When to use
The OpenAICompatibleLMInvoker
is designed to interact with endpoints that are compatible with OpenAI's chat
completion API contract. This includes but are not limited to:
1. DeepInfra (https://deepinfra.com/)
2. DeepSeek (https://deepseek.com/)
3. Groq (https://groq.com/)
4. OpenRouter (https://openrouter.ai/)
5. Text Generation Inference (https://github.com/huggingface/text-generation-inference)
6. Together.ai (https://together.ai/)
7. vLLM (https://vllm.ai/)
When using this invoker, please note that the supported features and capabilities may vary between different
endpoints and language models. Using features that are not supported by the endpoint will result in an error.
Basic usage
The OpenAICompatibleLMInvoker
can be used as follows:
lm_invoker = OpenAICompatibleLMInvoker(
model_name="llama3-8b-8192",
base_url="https://api.groq.com/openai/v1",
api_key="<your-api-key>"
)
result = await lm_invoker.invoke("Hi there!")
Input types
- Text.
- Audio, with extensions depending on the language model's capabilities.
- Image, with extensions depending on the language model's capabilities.
Non-text inputs must be of valid file extensions and can be passed as an
Attachment
object.
Non-text inputs can only be passed with the user
role.
Usage example:
text = "What animal is in this image?"
image = Attachment.from_path("path/to/local/image.png")
prompt = [(PromptRole.USER, [text, image])]
result = await lm_invoker.invoke(prompt)
Tool calling
Tool calling is a feature that allows the language model to call tools to perform tasks.
Tools can be passed to the via the tools
parameter as a list of LangChain's Tool
objects.
When tools are provided and the model decides to call a tool, the tool calls are stored in the
tool_calls
attribute in the output.
Usage example:
lm_invoker = OpenAICompatibleLMInvoker(..., tools=[tool_1, tool_2])
Output example:
LMOutput(
response="Let me call the tools...",
tool_calls=[
ToolCall(id="123", name="tool_1", args={"key": "value"}),
ToolCall(id="456", name="tool_2", args={"key": "value"}),
]
)
Structured output
Structured output is a feature that allows the language model to output a structured response.
This feature can be enabled by providing a schema to the response_schema
parameter.
The schema must be either a JSON schema dictionary or a Pydantic BaseModel class.
If JSON schema is used, it must be compatible with Pydantic's JSON schema, especially for complex schemas.
For this reason, it is recommended to create the JSON schema using Pydantic's model_json_schema
method.
The language model also doesn't need to stream anything when structured output is enabled. Thus, standard
invocation will be performed regardless of whether the event_emitter
parameter is provided or not.
When enabled, the structured output is stored in the structured_output
attribute in the output.
1. If the schema is a JSON schema dictionary, the structured output is a dictionary.
2. If the schema is a Pydantic BaseModel class, the structured output is a Pydantic model.
Example 1: Using a JSON schema dictionary
Usage example:
schema = {
"title": "Animal",
"description": "A description of an animal.",
"properties": {
"color": {"title": "Color", "type": "string"},
"name": {"title": "Name", "type": "string"},
},
"required": ["name", "color"],
"type": "object",
}
lm_invoker = OpenAICompatibleLMInvoker(..., response_schema=schema)
Output example:
LMOutput(structured_output={"name": "Golden retriever", "color": "Golden"})
Example 2: Using a Pydantic BaseModel class
Usage example:
class Animal(BaseModel):
name: str
color: str
lm_invoker = OpenAICompatibleLMInvoker(..., response_schema=Animal)
Output example:
LMOutput(structured_output=Animal(name="Golden retriever", color="Golden"))
Analytics tracking
Analytics tracking is a feature that allows the module to output additional information about the invocation.
This feature can be enabled by setting the output_analytics
parameter to True
.
When enabled, the following attributes will be stored in the output:
1. token_usage
: The token usage.
2. duration
: The duration in seconds.
3. finish_details
: The details about how the generation finished.
Output example:
LMOutput(
response="Golden retriever is a good dog breed.",
token_usage=TokenUsage(input_tokens=100, output_tokens=50),
duration=0.729,
finish_details={"finish_reason": "stop"},
)
When streaming is enabled, token usage is not supported. Therefore, the token_usage
attribute will be None
regardless of the value of the output_analytics
parameter.
Retry and timeout
The OpenAICompatibleLMInvoker
supports retry and timeout configuration.
By default, the max retries is set to 0 and the timeout is set to 30.0 seconds.
They can be customized by providing a custom RetryConfig
object to the retry_config
parameter.
Retry config examples:
retry_config = RetryConfig(max_retries=0, timeout=0.0) # No retry, no timeout
retry_config = RetryConfig(max_retries=0, timeout=10.0) # No retry, 10.0 seconds timeout
retry_config = RetryConfig(max_retries=5, timeout=0.0) # 5 max retries, no timeout
retry_config = RetryConfig(max_retries=5, timeout=10.0) # 5 max retries, 10.0 seconds timeout
Usage example:
lm_invoker = OpenAICompatibleLMInvoker(..., retry_config=retry_config)
Reasoning
Some language models support advanced reasoning capabilities. When using such reasoning-capable models, you can configure how much reasoning the model should perform before generating a final response by setting reasoning-related parameters.
The reasoning effort of reasoning models can be set via the reasoning_effort
parameter. This parameter
will guide the models on how many reasoning tokens it should generate before creating a response to the prompt.
The reasoning effort is only supported by some language models.
Available options include:
1. "low": Favors speed and economical token usage.
2. "medium": Favors a balance between speed and reasoning accuracy.
3. "high": Favors more complete reasoning at the cost of more tokens generated and slower responses.
This may differ between models. When not set, the reasoning effort will be equivalent to None by default.
When using reasoning models, some providers might output the reasoning summary. These will be stored in the
reasoning
attribute in the output.
Output example:
LMOutput(
response="Golden retriever is a good dog breed.",
reasoning=[Reasoning(id="", reasoning="Let me think about it...")],
)
When streaming is enabled along with reasoning and the provider supports reasoning output, the reasoning token
will be streamed with the EventType.DATA
event type.
Streaming output example: ```python {"type": "data", "value": '{"data_type": "thinking_start", "data_value": ""}', ...} {"type": "data", "value": '{"data_type": "thinking", "data_value": "Let me think "}', ...} {"type": "data", "value": '{"data_type": "thinking", "data_value": "about it..."}', ...} {"type": "data", "value": '{"data_type": "thinking_end", "data_value": ""}', ...} {"type": "response", "value": "Golden retriever ", ...} {"type": "response", "value": "is a good dog breed.", ...}
Setting reasoning-related parameters for non-reasoning models will raise an error.
Output types
The output of the OpenAICompatibleLMInvoker
is of type MultimodalOutput
, which is a type alias that can
represent:
1. str
: The text response if no additional output is needed.
2. LMOutput
: A Pydantic model with the following attributes if any additional output is needed:
2.1. response (str): The text response.
2.2. tool_calls (list[ToolCall]): The tool calls, if the tools
parameter is defined and the language
model decides to invoke tools. Defaults to an empty list.
2.3. structured_output (dict[str, Any] | BaseModel | None): The structured output, if the response_schema
parameter is defined. Defaults to None.
2.4. token_usage (TokenUsage | None): The token usage analytics, if the output_analytics
parameter is
set to True
. Defaults to None.
2.5. duration (float | None): The duration of the invocation in seconds, if the output_analytics
parameter is set to True
. Defaults to None.
2.6. finish_details (dict[str, Any] | None): The details about how the generation finished, if the
output_analytics
parameter is set to True
. Defaults to None.
2.7. reasoning (list[Reasoning]): The reasoning objects. Currently not supported. Defaults to an empty list.
2.8. citations (list[Chunk]): The citations. Currently not supported. Defaults to an empty list.
2.9. code_exec_results (list[CodeExecResult]): The code execution results. Currently not supported.
Defaults to an empty list.
Initializes a new instance of the OpenAICompatibleLMInvoker class.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
model_name |
str
|
The name of the language model hosted on the OpenAI compatible endpoint. |
required |
base_url |
str
|
The base URL for the OpenAI compatible endpoint. |
required |
api_key |
str | None
|
The API key for authenticating with the OpenAI compatible endpoint.
Defaults to None, in which case the |
None
|
model_kwargs |
dict[str, Any] | None
|
Additional model parameters. Defaults to None. |
None
|
default_hyperparameters |
dict[str, Any] | None
|
Default hyperparameters for invoking the model. Defaults to None. |
None
|
tools |
list[Tool] | None
|
Tools provided to the language model to enable tool calling. Defaults to None. |
None
|
response_schema |
ResponseSchema | None
|
The schema of the response. If provided, the model will output a structured response as defined by the schema. Supports both Pydantic BaseModel and JSON schema dictionary. Defaults to None. |
None
|
output_analytics |
bool
|
Whether to output the invocation analytics. Defaults to False. |
False
|
retry_config |
RetryConfig | None
|
The retry configuration for the language model. Defaults to None, in which case a default config with no retry and 30.0 seconds timeout is used. |
None
|
reasoning_effort |
str | None
|
The reasoning effort for the language model. Defaults to None. |
None
|
bind_tools_params |
dict[str, Any] | None
|
Deprecated parameter to add tool calling capability.
If provided, must at least include the |
None
|
with_structured_output_params |
dict[str, Any] | None
|
Deprecated parameter to instruct the
model to produce output with a certain schema. If provided, must at least include the |
None
|
set_response_schema(response_schema)
Sets the response schema for the language model hosted on the OpenAI compatible endpoint.
This method sets the response schema for the language model hosted on the OpenAI compatible endpoint. Any existing response schema will be replaced.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
response_schema |
ResponseSchema | None
|
The response schema to be used. |
required |