AI Reasoners

27 February 2025
AILLM

What Are AI Reasoners?

AI reasoners enable more structured, explicit and deliberate problem solving compared to standard large language model outputs. They are an evolution in how AI systems, more specifically LLMs, approach complex tasks by incorporating more explicit thinking processes. Most AI companies have now released reasoning models, like OpenAIs o1 to o3 model family, Anthropics Claude 3.7 Sonnet or Deepseeks r1.

How AI Reasoners Work

Fundamentally, reasoners work on the principle of breaking down problems into manageable steps and explicitly work through them before producing a final answer. This process involves several key mechanisms:

1. Step-by-Step Reasoning

Rather than producing an answer in one go, they take multiple steps:

  1. Parse the initial problem
  2. Identify what information is needed and what reasoning methods to apply
  3. Work through the intermediate steps explicitly
  4. Arrive at the final conclusion This resembles the human thought process, similar to when we solve a hard problem by writing out intermediate steps and solving them to reach the final solution.

2. Technical Implementation Approaches

From a technical perspective, reasoners can be implemented in different ways:

Chain-of-thought Prompting

By including phrases like “Let’s think step by step” in the prompt, the model is encouraged to think aloud before answering. This will lead to the generation of intermediate reasoning steps.

Self-Consistency Methods

These methods involve generating multiple reasoning paths for the same problem and selecting the most consistent answer. This helps to filter out inconsistencies or logical errors.

Reflection Mechanisms or Verifiers

By “critiquing” their own reasoning or by using verification modules, advanced reasoners can identify potential errors or gaps in their logic autonomically.

3. Architecture Integration

Typically, a reasoner operates as follows:

User Query -> Input Processor -> Reasoning Engine -> Verification Module -> Response Generator

The reasoning engine generally contains:

  • A component that breaks down the problem
  • A memory component to track intermediate results
  • Mechanisms to select reasoning strategies

Benefits of Reasoners

Reasoners offer several advantages over standard LLM outputs:

  1. Better Accuracy: Reasoners are less likely to make simple logical errors
  2. Verifiability: By outputting explicit intermediate steps, users can follow the AI’s thinking process and verify it
  3. Complex Problem Handling: Problems like hard math problems, logical thinking or detailed analysis are better handled by reasoners
  4. Reduced Hallucination: Explicit reasoning grounds responses in logical thinking instead of pure pattern matching, which can reduce hallucination

Example Use Cases

Code Debugging

def calculate_average(numbers):
    total = 0
    for num in numbers:
        total += num
    return total / len(numbers)

The above function crashes when the numbers list is empty, leading to a division by zero.

A reasoner might go through the following thinking steps:

  1. Let’s run the function with an empty list: numbers = []
  2. We initialize total = 0
  3. The for loop executes 0 times, so total stays at 0
  4. We therefore return 0 / 0, which leads to a python error
  5. We should therefore add a guard clause for an empty list

Suggested Fix:

def calculate_average(numbers):
    if not numbers:  # Check if the list is empty
        return None  # Or another appropriate default value
    total = 0
    for num in numbers:
        total += num
    return total / len(numbers)

Logical Reasoning for Scheduling Problem

Consider the following problem:

You need to schedule 5 one-hour meetings with 3 different clients. Client A is available Monday and Wednesday afternoons. Client B is available Monday, Tuesday, and Friday mornings. Client C is available Wednesday and Thursday all day. You need to meet with Client A twice, Client B twice, and Client C once. What's a valid schedule?

A reasoner would break this problem down systematically, resulting in something like this:

  • Step 1: Organize all availability information
    • Client A: Monday PM, Wednesday PM
    • Client B: Monday AM, Tuesday AM, Friday AM
    • Client C: Wednesday AM + PM, Thursday AM + PM
  • Step 2: Determine the constraints
    • Need 2 meetings with Client A
    • Need 2 meetings with Client B
    • Need 1 meeting with Client C
  • Step 3: Build a schedule
    • Client A (1): Wednesday PM
    • Client A (2): Monday PM
    • Client B (1): Monday AM
    • Client B (2): Tuesday AM
    • Client C (1): Thursday AM or PM
  • Step 4: Verify conflicts
    • Monday: Client A (PM), Client B (AM) → No conflict
    • Tuesday: Client B (AM) → No conflict
    • Wednesday: Client A (PM) → No conflict
    • Thursday: Client C (AM or PM) → No conflict
  • This is a valid schedule satisfying all constraints

Limitations and Challenges

Reasoners offer a lot of advantages, but also come with some challenges:

  1. Computational Overhead: The explicit reasoning process requires additional tokens and also more processing time
  2. Logic Errors: Even reasoners can still make subtle logic errors, especially in complex scenarios
  3. Verification Challenges: The creation of a verification module might be as hard as solving the problem itself