OpenAI Chat

Using OpenAI Chat Completions API with Upsonic

Overview

OpenAI Chat Completions API provides access to GPT-4o, GPT-5, and other chat models. This is the standard API for conversational interactions.

Model Class: OpenAIChatModel

Authentication

export OPENAI_API_KEY="sk-..."

Examples

from upsonic import Agent, Task
from upsonic.models.openai import OpenAIChatModel

model = OpenAIChatModel(model_name="gpt-4o")
agent = Agent(model=model)

task = Task("Hello, how are you?")
result = agent.do(task)
print(result)

Model Settings

You can set model parameters in two ways: on the model or on the Agent.

On the model:

from upsonic import Agent, Task
from upsonic.models.openai import OpenAIChatModel, OpenAIChatModelSettings

model = OpenAIChatModel(
    model_name="gpt-4o-mini",
    settings=OpenAIChatModelSettings(max_tokens=1024, temperature=0.7)
)
agent = Agent(model=model)

On the Agent (with model string or model instance):

from upsonic import Agent, Task
from upsonic.models.openai import OpenAIChatModelSettings

agent = Agent(
    model="openai/gpt-4o-mini",
    settings=OpenAIChatModelSettings(max_tokens=1024, temperature=0.7)
)

Parameters

Parameter	Type	Description	Default	Source
max_tokens	int	Maximum tokens to generate	Model-specific	Base
temperature	float	Sampling temperature (0.0-2.0)	1.0	Base
top_p	float	Nucleus sampling threshold	1.0	Base
seed	int	Random seed for deterministic outputs	None	Base
stop_sequences	list[str]	Sequences that stop generation	None	Base
presence_penalty	float	Penalty for token presence (-2.0 to 2.0)	0.0	Base
frequency_penalty	float	Penalty for token frequency (-2.0 to 2.0)	0.0	Base
logit_bias	dict[str, int]	Modify token likelihoods	None	Base
parallel_tool_calls	bool	Allow parallel tool calls	True	Base
timeout	float	Request timeout in seconds	600	Base
extra_headers	dict[str, str]	Additional HTTP headers	None	Base
extra_body	object	Additional request body params	None	Base
openai_reasoning_effort	'low' | 'medium' | 'high'	Computational effort for reasoning models	None	Specific
openai_logprobs	bool	Include log probabilities in response	False	Specific
openai_top_logprobs	int	Number of top log probs to return (1-20)	None	Specific
openai_user	str	Unique user identifier for abuse monitoring	None	Specific
openai_service_tier	'auto' | 'default' | 'flex' | 'priority'	Service tier for request routing	’auto’	Specific
openai_prediction	ChatCompletionPredictionContentParam	Enable predicted outputs	None	Specific