> ## Documentation Index
> Fetch the complete documentation index at: https://docs.oxen.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Chat Completions

> Generate text with language models in minutes

## Overview

Generate text responses from language models using the OpenAI-compatible chat completions API. Supports streaming, vision, audio, documents (PDFs), tool calling, and structured output.

## Minimal Example

<CodeGroup>
  ```python Python theme={null}
  from openai import OpenAI

  client = OpenAI(
      base_url="https://hub.oxen.ai/api/ai",
      api_key="YOUR_API_KEY",
  )

  response = client.chat.completions.create(
      model="claude-sonnet-4-6",
      messages=[{"role": "user", "content": "What is Oxen.ai?"}],
      max_tokens=200,
  )

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

  ```bash cURL theme={null}
  curl -X POST https://hub.oxen.ai/api/ai/chat/completions \
    -H "Authorization: Bearer YOUR_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{
      "model": "claude-sonnet-4-6",
      "messages": [{"role": "user", "content": "What is Oxen.ai?"}],
      "max_tokens": 200
    }'
  ```
</CodeGroup>

## With Streaming

<CodeGroup>
  ```python Python theme={null}
  from openai import OpenAI

  client = OpenAI(
      base_url="https://hub.oxen.ai/api/ai",
      api_key="YOUR_API_KEY",
  )

  stream = client.chat.completions.create(
      model="gemini-3-1-flash-lite-preview",
      messages=[{"role": "user", "content": "Write a haiku about data"}],
      stream=True,
  )

  for chunk in stream:
      content = chunk.choices[0].delta.content
      if content:
          print(content, end="", flush=True)
  print()
  ```

  ```bash cURL theme={null}
  curl -X POST https://hub.oxen.ai/api/ai/chat/completions \
    -H "Authorization: Bearer YOUR_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{
      "model": "gemini-3-1-flash-lite-preview",
      "messages": [{"role": "user", "content": "Write a haiku about data"}],
      "stream": true
    }'
  ```
</CodeGroup>

## With a Document (PDF)

Attach a PDF with a `file` content part. Oxen.ai translates the document to each
provider's native format, so it works the same regardless of which model you
call.

<CodeGroup>
  ```python Python theme={null}
  import base64
  from openai import OpenAI

  client = OpenAI(
      base_url="https://hub.oxen.ai/api/ai",
      api_key="YOUR_API_KEY",
  )

  with open("report.pdf", "rb") as f:
      file_data = "data:application/pdf;base64," + base64.standard_b64encode(f.read()).decode()

  response = client.chat.completions.create(
      model="claude-sonnet-4-6",
      messages=[
          {
              "role": "user",
              "content": [
                  {"type": "file", "file": {"filename": "report.pdf", "file_data": file_data}},
                  {"type": "text", "text": "Summarize the key findings."},
              ],
          }
      ],
  )

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

  ```bash cURL theme={null}
  FILE_DATA="data:application/pdf;base64,$(base64 < report.pdf | tr -d '\n')"
  curl -X POST https://hub.oxen.ai/api/ai/chat/completions \
    -H "Authorization: Bearer YOUR_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{
      "model": "claude-sonnet-4-6",
      "messages": [{
        "role": "user",
        "content": [
          {"type": "file", "file": {"filename": "report.pdf", "file_data": "'"$FILE_DATA"'"}},
          {"type": "text", "text": "Summarize the key findings."}
        ]
      }]
    }'
  ```
</CodeGroup>

### Reference a document by URL

You can also point at a PDF by URL (handy for files generated in a
[workspace](/concepts/workspaces)):

<CodeGroup>
  ```python Python theme={null}
  from openai import OpenAI

  client = OpenAI(
      base_url="https://hub.oxen.ai/api/ai",
      api_key="YOUR_API_KEY",
  )

  pdf_url = "https://arxiv.org/pdf/1706.03762"

  response = client.chat.completions.create(
      model="claude-sonnet-4-6",
      messages=[
          {
              "role": "user",
              "content": [
                  {"type": "file", "file": {"file_url": pdf_url}},
                  {"type": "text", "text": "Summarize the key findings."},
              ],
          }
      ],
  )

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

  ```bash cURL theme={null}
  curl -X POST https://hub.oxen.ai/api/ai/chat/completions \
    -H "Authorization: Bearer YOUR_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{
      "model": "claude-sonnet-4-6",
      "messages": [{
        "role": "user",
        "content": [
          {"type": "file", "file": {"file_url": "https://arxiv.org/pdf/1706.03762"}},
          {"type": "text", "text": "Summarize the key findings."}
        ]
      }]
    }'
  ```
</CodeGroup>

The URL must be publicly accessible (and unexpired, if presigned). Only
`application/pdf` is supported, and a document must be 24 MB or smaller;
other inputs return a `400`. See the
[reference](/inference-api/reference/chat_completions) for details.

## What's Next

* [Chat Completions Reference](/inference-api/reference/chat_completions) for the full parameter list
* [Image Generation Quick Start](/inference-api/quickstart/image-generation) to generate images
* [Video Generation Quick Start](/inference-api/quickstart/video-generation) to generate videos