Build an OpenAI API Chat Completions request
Source:R/openai_completions.R
oai_build_completions_request.RdThis function constructs a httr2 request object specifically tailored for interacting with OpenAI's Chat Completions API. It handles the formatting of messages, model parameters, and optional JSON schema for structured responses.
Usage
oai_build_completions_request(
input,
endpointr_id = NULL,
model = "gpt-4.1-nano",
temperature = 0,
max_tokens = 500L,
schema = NULL,
system_prompt = NULL,
key_name = "OPENAI_API_KEY",
endpoint_url = "https://api.openai.com/v1/chat/completions",
timeout = 20,
max_retries = 5
)Arguments
- input
Text input to send to the model
- endpointr_id
An id that will persist through to response
- model
OpenAI model to use (default: "gpt-4.1-nano")
- temperature
Sampling temperature (0-2), higher values = more randomness
- max_tokens
Maximum tokens in response
- schema
Optional JSON schema for structured output (json_schema object or list)
- system_prompt
Optional system prompt
- key_name
Environment variable name for API key
- endpoint_url
OpenAI API endpoint URL
- timeout
Request timeout in seconds
- max_retries
Maximum number of retry attempts for failed requests
Details
This function simplifies the process of making calls to the OpenAI Chat Completions API by assembling the request body according to the API's specifications.
The input and system_prompt (if provided) are automatically structured
into the required 'messages' array format for the API.
For structured outputs (JSON mode), you will need to provide a valid JSON schema
via the schema parameter. This can be a pre-formatted list or an object of
class "json_schema". If a schema is provided, the function will automatically
set schema$additionalProperties <- FALSE and ensure schema$strict <- TRUE
(if strict is not already defined in the schema) to encourage more predictable
and reliable structured outputs from the API. It's also a good idea
to set temperature to 0 when extracting structured outputs.