Skip to main content
The /v1/chat/completions endpoint is the primary interface for text-based workflows. It supports streaming, tool calling, and structured outputs across all providers.

​
Standard Request

curl --request POST \
  --url https://api.inworld.ai/v1/chat/completions \
  --header 'Authorization: Bearer <your-api-key>' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "auto",
    "messages": [
      {"role": "system", "content": "You are a helpful assistant."},
      {"role": "user", "content": "Write a 50-word bio for a software engineer."}
    ],
    "stream": true
  }'

​
Multimodal Inputs

To send images or audio alongside text, use the array form of content with typed content blocks.

​
Images

Use image_url with a base64 data URI or an HTTP URL. Google AI Studio and Vertex AI require base64 data URIs; other providers also accept HTTP URLs. 
curl --request POST \
  --url https://api.inworld.ai/v1/chat/completions \
  --header 'Authorization: Bearer <your-api-key>' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "google-ai-studio/gemini-2.5-flash",
    "messages": [
      {
        "role": "user",
        "content": [
          { "type": "text", "text": "Describe this image." },
          { "type": "image_url", "image_url": { "url": "data:image/jpeg;base64,/9j/4AAQ..." } }
        ]
      }
    ]
  }'

​
Audio

Use input_audio with base64-encoded audio data: 
curl --request POST \
  --url https://api.inworld.ai/v1/chat/completions \
  --header 'Authorization: Bearer <your-api-key>' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "google-ai-studio/gemini-2.5-flash",
    "messages": [
      {
        "role": "user",
        "content": [
          { "type": "text", "text": "Transcribe this audio." },
          { "type": "input_audio", "input_audio": { "data": "UklGRi...", "format": "wav" } }
        ]
      }
    ]
  }'
Multimodal support depends on the underlying model. Refer to the provider’s documentation for supported input types, formats, and limits.

​
Advanced Features

​
Tool Calling (Function Calling)

Inworld Router normalizes tool calling. You define tools in the OpenAI format, and the router translates them for Anthropic or Google models.

​
Structured Outputs (JSON Mode)

Force the model to return valid JSON by setting response_format: { "type": "json_object" }. Inworld Router ensures the underlying provider respects this constraint.

​
Streaming

Real-time token streaming is supported for all providers. The stream format is identical to OpenAI’s Server-Sent Events (SSE). See Web search for extra_body.web_search, web_search_options, and citation annotations.