Learn SARSA the Easy Way: Your First Temporal Difference Algorithm
Last Updated on November 11, 2025 by Editorial Team
Author(s): Rem E
Originally published on Towards AI.
Tutorial 9.1: Implementing the SARSA Algorithm for Our Maze Problem
Now we’re ready to start implementing our first Temporal Difference (TD) method: SARSA!
This tutorial builds on Tutorial 8.2, so make sure to check that one out first if you haven’t already.
If you’re not yet familiar with the SARSA algorithm, take a look at my previous story: Temporal Difference Learning: The Most Powerful RL Solution.
Ready? Let’s dive into the implementation!

This tutorial covers the implementation of the SARSA algorithm, explaining its core components and how it improves learning through the utilization of the Q-value updates for selecting actions and refining the policy over time. It details the project setup, initialization of variables, including the learning rate and discount factor, as well as the epsilon decay strategy to optimize action selection leading to the discovery of near-optimal policies.
Read the full blog for free on Medium.
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