Remove Reasoning from Response

2025-02-17 16:24 UTC gpt-4o Open in ChatGPT ↗

To remove the reasoning portion from the response string and extract only the actual response that comes after the </think> marker, you can use Python’s split function or regular expressions.

Method 1: Using `split`

This method is simple and works if the </think> marker is always present in the response.

def extract_response(response: str):
    return response.split("</think>")[-1].strip()

# Example
response = "This is the reasoning explanation. </think> Here is the actual response."
clean_response = extract_response(response)
print(clean_response)  # Output: "Here is the actual response."

Method 2: Using Regular Expressions

If the format varies, a regex approach provides more flexibility.

import re

def extract_response(response: str):
    match = re.search(r"</think>\s*(.*)", response, re.DOTALL)
    return match.group(1).strip() if match else response

# Example
response = "This is the reasoning explanation. </think> Here is the actual response."
clean_response = extract_response(response)
print(clean_response)  # Output: "Here is the actual response."

Let me know if you need a modification based on your response format! 🚀

Of course! Let’s break down Method 2 (Using Regular Expressions) step by step in a way that’s easy to understand.

What is Regular Expression (Regex)?

A regular expression (regex) is a pattern-matching technique used to find and manipulate text. Python provides a built-in module called re that allows us to use regex.

Breaking Down the Code

import re  # Importing the regular expressions module

def extract_response(response: str):
    # Use regex to find everything AFTER '</think>'
    match = re.search(r"</think>\s*(.*)", response, re.DOTALL)

    # If there's a match, return only the actual response (after '</think>')
    return match.group(1).strip() if match else response

Understanding the Regex Pattern:

r"</think>\s*(.*)"

Let’s break this pattern down:

</think> – This literally looks for the marker </think>.
\s* – This means “match any whitespace characters (spaces, newlines, tabs) after </think>”. The * means “match zero or more times”.
(.*) – The parentheses capture everything after </think>, including newlines.
- . means “any character”.
- * means “zero or more occurrences of any character”.

The re.DOTALL flag ensures that . also matches newlines, allowing multi-line responses.

Example in Action

response = """This is the reasoning explanation.
It explains the logic before providing an answer.
</think> Here is the actual response."""

When we run:

clean_response = extract_response(response)
print(clean_response)

Output:

Here is the actual response.

✅ The reasoning part is removed!

What Happens If `</think>` is Missing?

If there’s no </think> in the response, the function will return the original response without any changes.

response_without_think = "This is a response without the think marker."
print(extract_response(response_without_think))

Output:

This is a response without the think marker.

✅ This ensures the function won’t break if the marker is missing.

Why Use Regular Expressions Instead of `split`?

If the text format changes slightly (e.g., extra spaces, multiple lines), regex can handle it more flexibly.
split("</think>")[-1] works but doesn’t allow fine control over whitespace and newlines.

Final Thoughts

If you’re new to Python, this regex approach is a powerful and flexible way to extract text from structured responses. If you’re unsure about regex, the split method is a simpler alternative.

Let me know if you need more explanation! 🚀