Tool Calling

{
  "type": "function",
  "function": {
    "name": "get_current_time",
    "description": "Get the current time in an IANA timezone, e.g. Asia/Dhaka.",
    "parameters": {
      "type": "object",
      "properties": {
        "timezone": { "type": "string", "description": "IANA timezone name" }
      },
      "required": ["timezone"]
    }
  }
}

{
  "role": "assistant",
  "content": null,
  "tool_calls": [
    {
      "id": "call_01",
      "type": "function",
      "function": { "name": "get_current_time", "arguments": "{\"timezone\": \"Asia/Dhaka\"}" }
    }
  ]
}

import json
import os
from datetime import datetime
from zoneinfo import ZoneInfo

from openai import OpenAI

client = OpenAI(base_url="https://tokens.bd/v1", api_key=os.environ["TOKENS_API_KEY"])
MODEL = "deepseek/deepseek-v4.1-flash"


def get_current_time(timezone: str) -> dict:
    return {"timezone": timezone, "time": datetime.now(ZoneInfo(timezone)).isoformat()}


def add(a: float, b: float) -> dict:
    return {"result": a + b}


FUNCTIONS = {"get_current_time": get_current_time, "add": add}

TOOLS = [
    {
        "type": "function",
        "function": {
            "name": "get_current_time",
            "description": "Get the current time in an IANA timezone, e.g. Asia/Dhaka.",
            "parameters": {
                "type": "object",
                "properties": {"timezone": {"type": "string"}},
                "required": ["timezone"],
            },
        },
    },
    {
        "type": "function",
        "function": {
            "name": "add",
            "description": "Add two numbers.",
            "parameters": {
                "type": "object",
                "properties": {"a": {"type": "number"}, "b": {"type": "number"}},
                "required": ["a", "b"],
            },
        },
    },
]

messages = [
    {"role": "user", "content": "What time is it in Dhaka and in London? Also, what is 1250.5 + 349.5?"}
]

for _ in range(8):  # hard stop so a confused model can't loop forever
    resp = client.chat.completions.create(
        model=MODEL, messages=messages, tools=TOOLS, tool_choice="auto", max_tokens=1024
    )
    msg = resp.choices[0].message
    messages.append(msg.model_dump(exclude_none=True))

    if not msg.tool_calls:
        print(msg.content)
        break

    for call in msg.tool_calls:
        fn = FUNCTIONS.get(call.function.name)
        try:
            args = json.loads(call.function.arguments or "{}")
            result = fn(**args) if fn else {"error": f"unknown tool {call.function.name}"}
        except Exception as exc:  # report errors back to the model instead of crashing
            result = {"error": str(exc)}
        messages.append(
            {"role": "tool", "tool_call_id": call.id, "content": json.dumps(result)}
        )
else:
    print("Stopped after 8 rounds without a final answer.")

import os
import anthropic

client = anthropic.Anthropic(base_url="https://tokens.bd", api_key=os.environ["TOKENS_API_KEY"])

tools = [{
    "name": "add",
    "description": "Add two numbers.",
    "input_schema": {
        "type": "object",
        "properties": {"a": {"type": "number"}, "b": {"type": "number"}},
        "required": ["a", "b"],
    },
}]
messages = [{"role": "user", "content": "What is 1250.5 + 349.5?"}]

resp = client.messages.create(
    model="deepseek/deepseek-v4.1-flash", max_tokens=1024, tools=tools, messages=messages
)
if resp.stop_reason == "tool_use":
    call = next(b for b in resp.content if b.type == "tool_use")
    total = call.input["a"] + call.input["b"]
    messages += [
        {"role": "assistant", "content": resp.content},
        {"role": "user", "content": [
            {"type": "tool_result", "tool_use_id": call.id, "content": str(total)}
        ]},
    ]
    resp = client.messages.create(
        model="deepseek/deepseek-v4.1-flash", max_tokens=1024, tools=tools, messages=messages
    )
print(resp.content[0].text)