An unofficial Go client for the OpenAI API.
For new text-generation, reasoning, tool-calling, and multi-turn integrations, start with the Responses API. Chat Completions remains available for existing integrations.
The client also covers embeddings, images, audio, moderation, files, fine-tuning, batches, vector stores, and legacy Assistants API surfaces.
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go get github.com/sashabaranov/go-openaiGo OpenAI requires Go 1.18 or later.
Set an OpenAI API key in your environment:
export OPENAI_API_KEY="<your key>"Then create a response and read its generated text:
package main
import (
"context"
"fmt"
"log"
"os"
openai "github.com/sashabaranov/go-openai"
)
func main() {
client := openai.NewClient(os.Getenv("OPENAI_API_KEY"))
response, err := client.CreateResponse(context.Background(), openai.CreateResponseRequest{
Model: openai.GPT5Dot6Sol,
Instructions: "You are a concise technical explainer.",
Input: "Why is the sky blue?",
})
if err != nil {
log.Fatal(err)
}
fmt.Println(response.GetOutputText())
}Input can be a string or a slice of typed input items. For reasoning, tools,
multimodal output, or custom processing, inspect response.Output instead of
using the GetOutputText convenience method.
Use PreviousResponseID when OpenAI should carry the earlier response context.
Resend Instructions on each call when they should continue to apply.
store := true
first, err := client.CreateResponse(ctx, openai.CreateResponseRequest{
Model: openai.GPT5Dot6Sol,
Instructions: "Answer as a travel guide.",
Input: "What should I see in Lisbon?",
Store: &store,
})
if err != nil {
return err
}
second, err := client.CreateResponse(ctx, openai.CreateResponseRequest{
Model: openai.GPT5Dot6Sol,
Instructions: "Answer as a travel guide.",
Input: "Which one is best on a rainy day?",
PreviousResponseID: first.ID,
Store: &store,
})
if err != nil {
return err
}
fmt.Println(second.GetOutputText())stream, err := client.CreateResponseStream(ctx, openai.CreateResponseRequest{
Model: openai.GPT5Dot6Sol,
Input: "Write a short story about a curious gopher.",
})
if err != nil {
return err
}
defer stream.Close()
for {
event, err := stream.Recv()
if errors.Is(err, io.EOF) {
break
}
if err != nil {
return err
}
if event.Type == openai.ResponseStreamEventOutputTextDelta {
fmt.Print(event.Delta)
}
}Choose a model based on the workload's reasoning, latency, and cost requirements.
| Constant | Model ID | Typical use |
|---|---|---|
GPT6Dot1Sol |
gpt-6.1-sol |
Complex coding and professional work |
GPT6Astra |
gpt-6-astra |
Most demanding reasoning and coding |
GPT6Sol |
gpt-6-sol |
Previous Sol model |
GPT6Luna |
gpt-6-luna |
Focused, high-volume work |
GPT-5.6 and earlier model constants remain available. GPT-6.1 Sol and Astra support
low, medium (default), high, xhigh, and max reasoning; they do not support
none or minimal. GPT-6 Sol and Luna also support none. Use Responses for tool
calling with GPT-6.1 Sol or Astra, or when combining GPT-6 reasoning with tools.
See GPT-6 guidance.
See the OpenAI model catalog for capabilities and availability. Model IDs are accepted as strings, so you can use a model before a named constant is added to this package.
Chat Completions remains supported for existing integrations:
response, err := client.CreateChatCompletion(ctx, openai.ChatCompletionRequest{
Model: openai.GPT4oMini,
Messages: []openai.ChatCompletionMessage{
{
Role: openai.ChatMessageRoleUser,
Content: "Hello!",
},
},
})
if err != nil {
return err
}
fmt.Println(response.Choices[0].Message.Content)For a new integration, prefer Responses unless you specifically need the Chat Completions request or response shape.
Use DefaultConfig to customize the HTTP client, base URL, organization, or
headers before constructing a client:
config := openai.DefaultConfig(os.Getenv("OPENAI_API_KEY"))
config.BaseURL = "https://your-compatible-endpoint.example/v1"
client := openai.NewClientWithConfig(config)For Azure OpenAI, start with DefaultAzureConfig and configure the deployment
mapping or API version required by your Azure resource.
API failures can be inspected with errors.As:
var apiError *openai.APIError
if errors.As(err, &apiError) {
fmt.Printf("OpenAI error: status=%d code=%v message=%s\n",
apiError.HTTPStatusCode, apiError.Code, apiError.Message)
}Runnable examples live in examples/:
- Responses API with multi-turn state
- Chat Completions
- Chat Completions with a function tool
- Image generation
- Speech to text
To run one:
go run ./examples/responsesSee the contributing guidelines before opening a pull request.
Thank you to all of the project's contributors and sponsors, including Carson Kahn of Spindle AI.
