---
title: "Mock Completion Responses - Save Testing Costs"
description: "Trying to test making LLM Completion calls without calling the LLM APIs ? Pass `mock_response` to `litellm.completion` and litellm will directly return the response without neededing the call the LLM API and spend $$"
type: skill
canonical_url: https://claudary.paisolsolutions.com/skills/mock-completion
source: "Claudary"
difficulty: intermediate
author: "Claude Code Knowledge Pack"
date: 2026-07-10T11:31:04.073Z
license: CC-BY-4.0
attribution: "Mock Completion Responses - Save Testing Costs — Claudary (https://claudary.paisolsolutions.com/skills/mock-completion)"
---

# Mock Completion Responses - Save Testing Costs
Trying to test making LLM Completion calls without calling the LLM APIs ? Pass `mock_response` to `litellm.completion` and litellm will directly return the response without neededing the call the LLM API and spend $$

## Overview

# Mock Completion Responses - Save Testing Costs

Trying to test making LLM Completion calls without calling the LLM APIs ? 
Pass `mock_response` to `litellm.completion` and litellm will directly return the response without neededing the call the LLM API and spend $$ 

## Using `completion()` with `mock_response`

```python
from litellm import completion 

model = "gpt-3.5-turbo"
messages = [{"role":"user", "content":"Why is LiteLLM amazing?"}]

completion(model=model, messages=messages, mock_response="It's simple to use and easy to get started")
```

## Building a pytest function using `completion`

```python
from litellm import completion
import pytest

def test_completion_openai():
    try:
        response = completion(
            model="gpt-3.5-turbo",
            messages=[{"role":"user", "content":"Why is LiteLLM amazing?"}],
            mock_response="LiteLLM is awesome"
        )
        # Add any assertions here to check the response
        print(response)
        print(response['choices'][0]['finish_reason'])
    except Exception as e:
        pytest.fail(f"Error occurred: {e}")
```

---

Source: [Claudary](https://claudary.paisolsolutions.com/skills/mock-completion) · https://claudary.paisolsolutions.com