OpenAI compatibility

Note: OpenAI compatibility is experimental and is subject to major adjustments including breaking changes. For fully-featured access to the Ollama API, see the Ollama Python library, JavaScript library and REST API.

Ollama provides experimental compatibility with parts of the OpenAI API to help connect existing applications to Ollama.

Usage

OpenAI Python library

from openai import OpenAI

client = OpenAI(
    base_url='http://localhost:11434/v1/',

    # required but ignored
    api_key='ollama',
)

chat_completion = client.chat.completions.create(
    messages=[
        {
            'role': 'user',
            'content': 'Say this is a test',
        }
    ],
    model='llama3',
)

OpenAI JavaScript library

import OpenAI from 'openai'

const openai = new OpenAI({
  baseURL: 'http://localhost:11434/v1/',

  // required but ignored
  apiKey: 'ollama',
})

const chatCompletion = await openai.chat.completions.create({
  messages: [{ role: 'user', content: 'Say this is a test' }],
  model: 'llama3',
})

`curl`

curl http://localhost:11434/v1/chat/completions \
    -H "Content-Type: application/json" \
    -d '{
        "model": "llama3",
        "messages": [
            {
                "role": "system",
                "content": "You are a helpful assistant."
            },
            {
                "role": "user",
                "content": "Hello!"
            }
        ]
    }'

Endpoints

`/v1/chat/completions`

Supported features

Chat completions
Streaming
JSON mode
Reproducible outputs
Vision
Function calling
Logprobs

Supported request fields

model
messages
- Text content
- Array of content parts
frequency_penalty
presence_penalty
response_format
seed
stop
stream
temperature
top_p
max_tokens
logit_bias
tools
tool_choice
user
n

Notes

finish_reason will always be stop
usage.prompt_tokens will be 0 for completions where prompt evaluation is cached

Models

Before using a model, pull it locally ollama pull:

ollama pull llama3

Default model names

For tooling that relies on default OpenAI model names such as gpt-3.5-turbo, use ollama cp to copy an existing model name to a temporary name:

ollama cp llama3 gpt-3.5-turbo

Afterwards, this new model name can be specified the model field:

curl http://localhost:11434/v1/chat/completions \
    -H "Content-Type: application/json" \
    -d '{
        "model": "gpt-3.5-turbo",
        "messages": [
            {
                "role": "user",
                "content": "Hello!"
            }
        ]
    }'