Openai compatible

OpenAI SDK compatibility

NeosantaraAI provides a compatibility layer that enables you to use the OpenAI SDK to test the NeosantaraAI API. With a few code changes, you can quickly evaluate NeosantaraAI model capabilities.

This compatibility layer is primarily intended to test and compare model capabilities, and is not considered a long-term or production-ready solution for most use cases. While we do intend to keep it fully functional and not make breaking changes, our priority is the reliability and effectiveness of the NeosantaraAI API.

For more information on known compatibility limitations, see Important OpenAI compatibility limitations.

If you encounter any issues with the OpenAI SDK compatibility feature, please let us know at [e-mail].

For the best experience and access to NeosantaraAI API full feature set, we recommend using our native API (check getting started guide).

Getting started with the OpenAI SDK

To use the OpenAI SDK compatibility feature, you’ll need to:

1. Use an official OpenAI SDK
2. Change the following
   • Update your base URL to point to NeosantaraAI’s API
   • Replace your API key with a NeosantaraAI API key
   • Update your model name to use a NeosantaraAI model
3. Review the documentation below for what features are supported

Quick start example

Python

from openai import OpenAI

client = OpenAI(
    api_key="NEOSANTARA_API_KEY",  # Your NeosantaraAI API key
    base_url="[https://api.neosantara.xyz/v1/](https://api.neosantara.xyz/v1/)"  # NeosantaraAI's API endpoint
)

response = client.chat.completions.create(
    model="nusantara-base", # NeosantaraAI model name
    messages=[
        {"role": "system", "content": "You are a helpful assistant."},
        {"role": "user", "content": "Who are you?"}
    ],
)

print(response.choices[0].message.content)

Important OpenAI compatibility limitations

API behavior

Here are the most substantial differences from using OpenAI:

• The strict parameter for function calling is ignored, which means the tool use JSON is not guaranteed to follow the supplied schema.
• Audio input is not supported; it will simply be ignored and stripped from input
• Prompt caching is not supported
• System messages are prepended to the first user message for some models.

Most unsupported fields are silently ignored rather than producing errors. These are all documented below.

Output quality considerations

If you’ve done lots of tweaking to your prompt, it’s likely to be well-tuned to OpenAI specifically.

System / Developer message hoisting

Most of the inputs to the OpenAI SDK clearly map directly to NeosantaraAI’s API parameters, but one distinct difference is the handling of system prompts. System messages are handled by prepending their content to the first user message for some underlying models, or passed as a system role to others.

Extended thinking support

NeosantaraAI supports advanced reasoning capabilities via its dedicated /v1/reasoning endpoint. This Anthropic-specific thinking parameter is ignored.

Python

response = client.chat.completions.create(
    model="nusantara-base",
    messages=...,
    # The 'thinking' parameter here will be ignored by NeosantaraAI
    extra_body={
        "thinking": { "type": "enabled", "budget_tokens": 2000 }
    }
)

Rate limits

Rate limits follow NeosantaraAI’s standard limits.

Detailed OpenAI Compatible API Support

Request fields

Simple fields

Field	Support status
model	Use NeosantaraAI model names
max_tokens	Fully supported
max_completion_tokens	Ignored (use max_tokens instead)
stream	Fully supported
stream_options	Ignored
top_p	Fully supported
parallel_tool_calls	Supported via tools array
stop	Fully supported
temperature	Fully supported
n	Must be exactly 1
logprobs	Ignored
metadata	Ignored
response_format	Fully supported (text, json_object)
prediction	Ignored
presence_penalty	Fully supported
frequency_penalty	Fully supported
seed	Ignored
service_tier	Ignored
audio	Ignored
logit_bias	Ignored
store	Ignored
user	Ignored
modalities	Ignored
top_logprobs	Ignored
reasoning_effort	Ignored (use /v1/reasoning endpoint instead)

tools / functions fields

Show fields

Tools

tools[n].function fields

Field	Support status
name	Fully supported
description	Fully supported
parameters	Fully supported
strict	Ignored

messages array fields

Show fields

Developer role

Fields for messages[n].role == "developer"

NeosantaraAI does not explicitly support a separate “developer” message role.

Field	Support status
content	Not applicable (ignored)
name	Ignored

Error message compatibility

The compatibility layer maintains consistent error formats with the OpenAI API. However, the detailed error messages will not be equivalent. We recommend only using the error messages for logging and debugging.

Header compatibility

While the OpenAI SDK automatically manages headers, here is the complete list of headers supported by NeosantaraAI’s API for developers who need to work with them directly.

Header	Support Status
x-ratelimit-limit-requests	Fully supported
x-ratelimit-limit-tokens	Fully supported
x-ratelimit-remaining-requests	Fully supported
x-ratelimit-remaining-tokens	Fully supported
x-ratelimit-reset-requests	Fully supported
x-ratelimit-reset-tokens	Fully supported
retry-after	Not supported
request-id	Not supported
openai-version	Not supported
authorization	Fully supported
openai-processing-ms	Not supported