Create Formatted Output

POST: https://www.kkiai.com/v1/messages

Given a prompt,, the model will return one or more predicted completions, and can also return the probability of alternative tokens at each position.

Create a completion for the provided messages and parameters.

Official documentation: https://docs.anthropic.com/en/docs/agents-and-tools/tool-use/overview#how-tool-use-works

Request Parameters

Authorization

Add the Authorization parameter to the Header, with its value being the Token concatenated after Bearer.

Example: Authorization: Bearer YOUR_API_KEY

Header Parameters

Parameter Name	Type	Required	Description	Example
`Content-Type`	string	Required		application/json
`Accept`	string	Required		application/json
`Authorization`	string	Required	API key used for authentication.	Bearer YOUR_API_KEY
`anthropic-beta`	string	Optional	Anthropic beta feature header.	structured-outputs-2025-11-13

Body Parameters (application/json)

Parameter Name	Type	Required	Description
`model`	string	Required	The ID of the model to use. For details on which models are available for use with the Chat API, see the model endpoint compatibility table.
`messages`	array[object]	Required	A list of messages comprising the conversation so far.
└ `role`	string	Required	The role of the message author, such as `user` or `assistant`.
└ `content`	string	Required	The text content of the message.
`temperature`	number	Optional	What sampling temperature to use, between 0 and 2. Higher values like 0.8 will make the output more random, while lower values like 0.2 will make it more focused and deterministic. We generally recommend altering this or `top_p`, but not both.
`top_p`	number	Optional	An alternative to sampling with temperature, called nucleus sampling, where the model considers the results of the tokens with top_p probability mass. So 0.1 means only the tokens comprising the top 10% probability mass are considered. We generally recommend altering this or `temperature`, but not both.
`n`	integer	Optional	Defaults to 1. How many chat completion choices to generate for each input message.
`stream`	boolean	Optional	Defaults to false. If set, partial message deltas will be sent, like in ChatGPT. Tokens will be sent as data-only server-sent events as they become available, with the stream terminated by a `data: [DONE]` message.
`stop`	string	Optional	Defaults to null. Up to 4 sequences where the API will stop generating further tokens.
`max_tokens`	integer	Optional	Defaults to inf. The maximum number of tokens to generate in the chat completion. The total length of input tokens and generated tokens is limited by the model's context length.
`presence_penalty`	number	Optional	Defaults to 0. A number between -2.0 and 2.0. Positive values penalize new tokens based on whether they appear in the text so far, increasing the model's likelihood to talk about new topics. See more information about frequency and presence penalties.
`frequency_penalty`	number	Optional	Defaults to 0. A number between -2.0 and 2.0. Positive values penalize new tokens based on their existing frequency in the text so far, decreasing the model's likelihood to repeat the same line verbatim. See more information about frequency and presence penalties.
`logit_bias`	object or null	Optional	Modify the likelihood of specified tokens appearing in the completion. Accepts a JSON object that maps tokens to an associated bias value from -100 to 100.
`user`	string	Optional	A unique identifier representing your end-user, which can help OpenAI monitor and detect abuse. Learn more.
`response_format`	object	Optional	An object specifying the format that the model must output.
`seed`	integer	Optional	This feature is in beta. If specified, our system will make a best effort to sample deterministically.
`tools`	array[string]	Required	A list of tools the model may call. Currently, only functions are supported as a tool.
`tool_choice`	object	Required	Controls which function, if any, the model calls.

Request Example

json

{
  "model": "claude-sonnet-4-5-20250929",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": "Extract the key information from this email: John Smith (john@example.com) is interested in our Enterprise plan and wants to schedule a demo for next Tuesday at 2pm."
    }
  ],
  "output_format": {
    "type": "json_schema",
    "schema": {
      "type": "object",
      "properties": {
        "name": { "type": "string" },
        "email": { "type": "string" },
        "plan_interest": { "type": "string" },
        "demo_requested": { "type": "boolean" }
      },
      "required": ["name", "email", "plan_interest", "demo_requested"],
      "additionalProperties": false
    }
  }
}

cURL Example

bash

curl --location --request POST 'https://www.kkiai.com/v1/messages' \
--header 'Accept: application/json' \
--header 'anthropic-beta: structured-outputs-2025-11-13' \
--header 'Authorization: Bearer YOUR_API_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "model": "claude-sonnet-4-5-20250929",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": "Extract the key information from this email: John Smith (john@example.com) is interested in our Enterprise plan and wants to schedule a demo for next Tuesday at 2pm."
    }
  ],
  "output_format": {
    "type": "json_schema",
    "schema": {
      "type": "object",
      "properties": {
        "name": { "type": "string" },
        "email": { "type": "string" },
        "plan_interest": { "type": "string" },
        "demo_requested": { "type": "boolean" }
      },
      "required": ["name", "email", "plan_interest", "demo_requested"],
      "additionalProperties": false
    }
  }
}'

Response

🟢 200 OK

Response Body

Parameter Name	Type	Required
`id`	string	Required
`object`	string	Required
`created`	integer	Required
`choices`	array[object]	Required
└ `index`	integer	Optional
└ `message`	object	Optional
└ `finish_reason`	string	Optional
`usage`	object	Required
└ `prompt_tokens`	integer	Required
└ `completion_tokens`	integer	Required
└ `total_tokens`	integer	Required

Response Example

json

{
  "id": "chatcmpl-123",
  "object": "chat.completion",
  "created": 1677652288,
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "\n\nHello there, how may I assist you today?"
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 9,
    "completion_tokens": 12,
    "total_tokens": 21
  }
}

Create Formatted Output ​

Request Parameters ​

Header Parameters ​

Body Parameters (application/json) ​

Request Example ​

cURL Example ​

Response ​

Response Body ​

Response Example ​