Responses API

Overview

The Responses API is an advanced endpoint that follows the OpenAI Responses API specification. Unlike Chat Completions, it supports built-in tools, structured outputs, and agent-like reasoning workflows natively.

Yunxin is one of the few API gateways that fully implements the Responses API — a critical milestone for agent-oriented applications.

Endpoint

POST /v1/responses

Request Body

{
  "model": "model-id",
  "input": "What is the weather in San Francisco?",
  "tools": [
    {
      "type": "web_search_preview"
    }
  ]
}

Parameters

Parameter	Type	Required	Description
`model`	string	Yes	Model ID to use
`input`	string/array	Yes	Input text or array of input items
`instructions`	string	No	System instructions for the model
`previous_response_id`	string	No	ID of a previous response to continue the conversation
`tools`	array	No	Array of tool definitions
`temperature`	number	No	Sampling temperature (0–2)
`max_output_tokens`	integer	No	Maximum output tokens
`stream`	boolean	No	Enable streaming
`metadata`	object	No	Arbitrary metadata to attach

Input Formats

The input field accepts multiple formats:

Simple text:

{
  "input": "Hello, how are you?"
}

Array of messages:

{
  "input": [
    {"role": "user", "content": "What is 2+2?"}
  ]
}

With previous response context:

{
  "input": [
    {"type": "message", "role": "user", "content": "Follow up question..."}
  ],
  "previous_response_id": "resp_abc123"
}

Built-in Tools

The Responses API supports built-in tools that don't require external implementation:

Tool	Description
`web_search_preview`	Search the web for real-time information
`code_interpreter`	Execute code for data analysis
`file_search`	Search through uploaded files

List Available Tools

GET /v1/responses/tools

Returns the list of built-in tools available for the Responses API.

Response

{
  "id": "resp_abc123",
  "object": "response",
  "created_at": 1709251200,
  "model": "model-id",
  "output": [
    {
      "type": "message",
      "role": "assistant",
      "content": [
        {
          "type": "output_text",
          "text": "Based on my search, the current weather in San Francisco is..."
        }
      ]
    }
  ],
  "usage": {
    "input_tokens": 15,
    "output_tokens": 42,
    "total_tokens": 57
  }
}

Examples

Basic Request

import httpx

response = httpx.post(
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "input": "Explain the theory of relativity."
    }
)

print(response.json())

With Web Search

response = httpx.post(
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "input": "What are the latest developments in fusion energy?",
        "tools": [{"type": "web_search_preview"}]
    }
)

With Instructions

response = httpx.post(
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "instructions": "You are a senior software engineer. Always provide code examples.",
        "input": "How do I implement a binary search tree?",
        "temperature": 0.3
    }
)

Streaming

import httpx

with httpx.stream(
    "POST",
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "input": "Write a poem about the ocean.",
        "stream": True
    }
) as response:
    for chunk in response.iter_lines():
        print(chunk)

Comparison with Chat Completions

Feature	Chat Completions	Responses API
Format	OpenAI Chat format	OpenAI Responses format
Built-in tools	No	Yes (web search, code interpreter)
Structured output	Via `response_format`	Native support
Agent workflows	Manual orchestration	Native support
Response chaining	Manual	Via `previous_response_id`
Compatibility	All OpenAI SDKs	Newer OpenAI SDK versions

Overview

Yunxin is one of the few API gateways that fully implements the Responses API — a critical milestone for agent-oriented applications.

Endpoint

POST /v1/responses

Request Body

{
  "model": "model-id",
  "input": "What is the weather in San Francisco?",
  "tools": [
    {
      "type": "web_search_preview"
    }
  ]
}

Parameters

Parameter	Type	Required	Description
`model`	string	Yes	Model ID to use
`input`	string/array	Yes	Input text or array of input items
`instructions`	string	No	System instructions for the model
`previous_response_id`	string	No	ID of a previous response to continue the conversation
`tools`	array	No	Array of tool definitions
`temperature`	number	No	Sampling temperature (0–2)
`max_output_tokens`	integer	No	Maximum output tokens
`stream`	boolean	No	Enable streaming
`metadata`	object	No	Arbitrary metadata to attach

Input Formats

The input field accepts multiple formats:

Simple text:

{
  "input": "Hello, how are you?"
}

Array of messages:

{
  "input": [
    {"role": "user", "content": "What is 2+2?"}
  ]
}

With previous response context:

{
  "input": [
    {"type": "message", "role": "user", "content": "Follow up question..."}
  ],
  "previous_response_id": "resp_abc123"
}

Built-in Tools

The Responses API supports built-in tools that don't require external implementation:

Tool	Description
`web_search_preview`	Search the web for real-time information
`code_interpreter`	Execute code for data analysis
`file_search`	Search through uploaded files

List Available Tools

GET /v1/responses/tools

Returns the list of built-in tools available for the Responses API.

Response

{
  "id": "resp_abc123",
  "object": "response",
  "created_at": 1709251200,
  "model": "model-id",
  "output": [
    {
      "type": "message",
      "role": "assistant",
      "content": [
        {
          "type": "output_text",
          "text": "Based on my search, the current weather in San Francisco is..."
        }
      ]
    }
  ],
  "usage": {
    "input_tokens": 15,
    "output_tokens": 42,
    "total_tokens": 57
  }
}

Examples

Basic Request

import httpx

response = httpx.post(
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "input": "Explain the theory of relativity."
    }
)

print(response.json())

With Web Search

response = httpx.post(
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "input": "What are the latest developments in fusion energy?",
        "tools": [{"type": "web_search_preview"}]
    }
)

With Instructions

response = httpx.post(
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "instructions": "You are a senior software engineer. Always provide code examples.",
        "input": "How do I implement a binary search tree?",
        "temperature": 0.3
    }
)

Streaming

import httpx

with httpx.stream(
    "POST",
    "https://api.yuhuanstudio.com/v1/responses",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
        "model": "model-id",
        "input": "Write a poem about the ocean.",
        "stream": True
    }
) as response:
    for chunk in response.iter_lines():
        print(chunk)

Comparison with Chat Completions

Feature	Chat Completions	Responses API
Format	OpenAI Chat format	OpenAI Responses format
Built-in tools	No	Yes (web search, code interpreter)
Structured output	Via `response_format`	Native support
Agent workflows	Manual orchestration	Native support
Response chaining	Manual	Via `previous_response_id`
Compatibility	All OpenAI SDKs	Newer OpenAI SDK versions

Overview

Endpoint

Request Body

Parameters

Input Formats

Built-in Tools

List Available Tools

Response

Examples

Basic Request

With Web Search

With Instructions

Streaming

Comparison with Chat Completions

On this page

Responses API

Overview

Endpoint

Request Body

Parameters

Input Formats

Built-in Tools

List Available Tools

Response

Examples

Basic Request

With Web Search

With Instructions

Streaming

Comparison with Chat Completions

On this page