Invoke your imported model

BedrockCompletion format is compatible with current Bedrock workflows and supports text-based inference requests.

Example request:

import json
import boto3

client = boto3.client('bedrock-runtime', region_name='us-east-1')

payload = {
    "prompt": "How is the rainbow formed?",
    "max_gen_len": 100,
    "temperature": 0.5
}

response = client.invoke_model(
    modelId='your-model-arn',
    body=json.dumps(payload),
    accept='application/json',
    contentType='application/json'
)

response_body = json.loads(response['body'].read())

Example response:

{
    "generation": " – A scientific explanation\nA rainbow is a beautiful natural phenomenon that occurs when sunlight passes through water droplets in the air. It is formed through a process called refraction, which is the bending of light as it passes from one medium to another.\nHere's a step-by-step explanation of how a rainbow is formed:\n1. Sunlight enters the Earth's atmosphere: The first step in forming a rainbow is for sunlight to enter the Earth's atmosphere. This sunlight is made up of a spectrum of",
    "prompt_token_count": 7,
    "generation_token_count": 100,
    "stop_reason": "length",
    "logprobs": null
}

BedrockCompletion supports structured outputs using response_format parameter with json_object and json_schema types.

OpenAICompletion format provides OpenAI Completions Schema compatibility. To use this format, include the max_tokens parameter instead of max_gen_len.

Example request:

import json
import boto3

client = boto3.client('bedrock-runtime', region_name='us-east-1')

payload = {
    "prompt": "How is the rainbow formed?",
    "max_tokens": 100,
    "temperature": 0.5
}

response = client.invoke_model(
    modelId='your-model-arn',
    body=json.dumps(payload),
    accept='application/json',
    contentType='application/json'
)

response_body = json.loads(response['body'].read())

Example response:

{
    "id": "cmpl-b09d5810bd64428f8a853be71c31f912",
    "object": "text_completion",
    "created": 1763166682,
    "choices": [
        {
            "index": 0,
            "text": " The formation of a rainbow is a complex process that involves the interaction of sunlight with water droplets in the air. Here's a simplified explanation: 1. Sunlight enters the Earth's atmosphere and is refracted, or bent, as it passes through the air. 2. When sunlight encounters a water droplet, such as a cloud, mist, or fog, it is refracted again and split into its individual colors, a process known as dispersion. 3. The refracted and",
            "finish_reason": "length"
        }
    ],
    "usage": {
        "prompt_tokens": 7,
        "total_tokens": 107,
        "completion_tokens": 100
    }
}

OpenAICompletion supports full structured outputs capabilities including json, regex, choice, and grammar constraints using the structured_outputs parameter.

OpenAIChatCompletion format provides full conversational Schema compatibility and supports both text and image inputs.

Example request:

import json
import boto3

client = boto3.client('bedrock-runtime', region_name='us-east-1')

payload = {
    "messages": [
        {
            "role": "user",
            "content": "How is the rainbow formed?"
        }
    ],
    "max_tokens": 100,
    "temperature": 0.5
}

response = client.invoke_model(
    modelId='your-model-arn',
    body=json.dumps(payload),
    accept='application/json',
    contentType='application/json'
)

response_body = json.loads(response['body'].read())

Example response:

{
    "id": "chatcmpl-1d84ce1d3d61418e8c6d1973f87173db",
    "object": "chat.completion",
    "created": 1763166683,
    "choices": [
        {
            "index": 0,
            "message": {
                "role": "assistant",
                "content": "A rainbow is a beautiful natural phenomenon that occurs when sunlight passes through water droplets in the air. The process of forming a rainbow involves several steps:\n\n1. **Sunlight**: The first requirement for a rainbow is sunlight. The sun should be shining brightly, but not directly overhead.\n2. **Water droplets**: The second requirement is water droplets in the air..."
            },
            "finish_reason": "length"
        }
    ],
    "usage": {
        "prompt_tokens": 41,
        "completion_tokens": 100,
        "total_tokens": 141
    }
}

OpenAIChatCompletion supports structured outputs using both response_format and structured_outputs parameters. For vision capabilities, include images in the content array with base64-encoded image data.