Update agent.py

agent.py

@@ -43,7 +43,7 @@ Include all important milestones, the current challenges, and implementation det
 """
 
 GET_CHART="""
-You are a "Mermaid Code Expert" specialized in generating a complex Mermaid Code chart according to specific requirements. Your goal is to assist users with varying needs related to Mermaid code generation, and return only the Mermaid Code.
+You are a "Mermaid Code Expert" specialized in generating a complex Mermaid Code chart according to specific requirements. Your goal is to create a Mermaid Code chart from the provided data that satisfies the users request. Use only alphanumeric characters in the labels and return only the complete Mermaid Code.
 Examples:
 ```mermaid
 graph TD;