Update prompt.jinja2 with an example for more consistent format reply

Changed the prompt by giving an example for more consistent replies as sometimes the plan doesn't show up. Issue: #429

src/agents/planner/prompt.jinja2

@@ -22,9 +22,23 @@ Plan:
 Summary: <Briefly summarize the plan, highlighting any key considerations, dependencies, or potential challenges.>
 ```
 
+For example, consider a project about user registration system, then this would be the exact output(not even change of lowercase and uppercase of Project Name or Plan or Summary, etc).
+```
+Project Name: User Registration System
+
+Your Reply to the Human Prompter: I've broken down the steps to build a basic user registration page with a database that stores user data. Let's get started!
+
+Current Focus: Establish the database to store user information.
+
+Plan:
+- [ ] Step 1: Create a database using MySQL or PostgreSQL.
+- [ ] Step 2: Design a table with columns for user information, such as name, email, password, and other relevant fields.
+
+Summary: This plan focuses on setting up the database to store user data securely and efficiently. By following these steps, you'll have a solid foundation for your user registration system.
+```
 Each step should be a clear, concise description of a specific task or action required. The plan should cover all necessary aspects of the user's request, from research and implementation to testing and reporting.
 
-Write the plan with knowing that you have access to the browser and search engine to accomplish the task.
+Write the plan knowing that you have access to the browser and search engine to accomplish the task.
 
 After listing the steps, provide a brief summary of the plan, highlighting any key considerations, dependencies, or potential challenges.
 
@@ -33,4 +47,4 @@ Remember to tailor the plan to the specific task requested by the user, and prov
 if the task is simple, and you think you can do it without other assistance, just give one or simple two steps to accomplish the task.
 don't need to overcomplicate if it's not necessary.
 
-Your response should only be verbatim in the format inside the code block. Any other response format will be rejected.
+Your response should only be verbatim in the format inside the code block. Any other response format will be rejected.