Documentation fix to code for Function calling

Documentation
,
2

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Already “reported” here

This was already noted, but no action has been taken:

Letting GPT-5.2 coding pal loose on the Python vs Javascript versions:

What to edit (errors only)

Using your JS snippet’s approximate line numbers:

  1. Line 23: getHoroscope is written to accept a string, but you pass it the parsed arguments object. Fix by changing the function signature to accept { sign }.

  2. After line 37: you must append the model’s first response.output back into the running input array:

    • add input.push(...response.output);

  3. Line 41: if (...) : is Python syntax and will crash parsing in JS. Replace with a normal JS if (...) { ... }.

  4. Line 43: get_horoscope is not defined (your function is getHoroscope). Call the right function name.

  5. Line 46: input_list is not defined (your list is input). Push into input.

  6. Line 49: json.dumps doesn’t exist in JS. Use JSON.stringify(...).

Patch (unified diff)

--- a/horoscope.js
+++ b/horoscope.js
@@
-function getHoroscope(sign) {
+function getHoroscope({ sign }) {
   return sign + " Next Tuesday you will befriend a baby otter.";
 }
@@
 let response = await openai.responses.create({
   model: "gpt-5",
   tools,
   input,
 });
 
+input.push(...response.output);
+
 response.output.forEach((item) => {
   if (item.type == "function_call") {
-    if (item.name == "get_horoscope"):
-      // 3. Execute the function logic for get_horoscope
-      const horoscope = get_horoscope(JSON.parse(item.arguments))
-      
-      // 4. Provide function call results to the model
-      input_list.push({
-          type: "function_call_output",
-          call_id: item.call_id,
-          output: json.dumps({
-            horoscope
-          })
-      })
+    if (item.name == "get_horoscope") {
+      // 3. Execute the function logic for get_horoscope
+      const horoscope = getHoroscope(JSON.parse(item.arguments));
+
+      // 4. Provide function call results to the model
+      input.push({
+        type: "function_call_output",
+        call_id: item.call_id,
+        output: JSON.stringify({ horoscope }),
+      });
+    }
   }
 });

Complete corrected code

import OpenAI from "openai";
const openai = new OpenAI();

// 1. Define a list of callable tools for the model
const tools = [
  {
    type: "function",
    name: "get_horoscope",
    description: "Get today's horoscope for an astrological sign.",
    parameters: {
      type: "object",
      properties: {
        sign: {
          type: "string",
          description: "An astrological sign like Taurus or Aquarius",
        },
      },
      required: ["sign"],
    },
  },
];

function getHoroscope({ sign }) {
  return sign + " Next Tuesday you will befriend a baby otter.";
}

// Create a running input list we will add to over time
let input = [
  { role: "user", content: "What is my horoscope? I am an Aquarius." },
];

// 2. Prompt the model with tools defined
let response = await openai.responses.create({
  model: "gpt-5",
  tools,
  input,
});

input.push(...response.output);

response.output.forEach((item) => {
  if (item.type == "function_call") {
    if (item.name == "get_horoscope") {
      // 3. Execute the function logic for get_horoscope
      const horoscope = getHoroscope(JSON.parse(item.arguments));

      // 4. Provide function call results to the model
      input.push({
        type: "function_call_output",
        call_id: item.call_id,
        output: JSON.stringify({ horoscope }),
      });
    }
  }
});

console.log("Final input:");
console.log(JSON.stringify(input, null, 2));

response = await openai.responses.create({
  model: "gpt-5",
  instructions: "Respond only with a horoscope generated by a tool.",
  tools,
  input,
});

// 5. The model should be able to give a response!
console.log("Final output:");
console.log(JSON.stringify(response.output, null, 2));

Functions return request shape - Responses

If you just want to send a call and see the AI answer with the required message sequence of a strict structured tool call and a tool response as input, not have it use your fake function, I created a “get code” on the “playground”:

import OpenAI from "openai";

const openai = new OpenAI({
  apiKey: process.env.OPENAI_API_KEY,
});

const response = await openai.responses.create({
  model: "gpt-4.1",
  input: [
    {
      "role": "system",
      "content": [
        {
          "type": "input_text",
          "text": "Horoscopes: Respond only with a tool-generated horoscope."
        }
      ]
    },
    {
      "role": "user",
      "content": [
        {
          "type": "input_text",
          "text": "What is my horoscope? I am an Aquarius."
        }
      ]
    },
    {
      "type": "function_call",
      "id": "fc_05cc35f2b4b0667a0169628083c55881908b6b5e57a74037a8",
      "call_id": "call_tZlYuKgqFz03Hrd3suLXFxDX",
      "name": "get_horoscope",
      "arguments": "{\"sign\":\"Aquarius\"}"
    },
    {
      "type": "function_call_output",
      "call_id": "call_tZlYuKgqFz03Hrd3suLXFxDX",
      "output": " Aquarius Next Tuesday you will befriend a baby otter."
    }
  ],
  tools: [
    {
      "type": "function",
      "name": "get_horoscope",
      "description": "Get today's horoscope for an astrological sign.",
      "parameters": {
        "type": "object",
        "properties": {
          "sign": {
            "type": "string",
            "description": "An astrological sign like Taurus or Aquarius"
          }
        },
        "required": [
          "sign"
        ],
        "additionalProperties": false
      },
      "strict": true
    }
  ],
  max_output_tokens: 2048,
  top_p: 0.5,
  store: false,
});