How to control agent's thoughts?

[Hetvi-Solanki]

Describe the bug

• We are getting too much of thinking from agent even for the simplest queries like "Hi"
• Is there any way to control the thoughts?
• I have tried setting thinking budget to small no. of tokens, yet it does not show any effect

To Reproduce

root_agent = Agent(
    name="manager",
    model=settings.GEMINI_MODEL,
    description="Manager agent",
    instruction=manager_instruction,
    generate_content_config=GenerateContentConfig(
        temperature=settings.TEMPERATURE,
        http_options=HttpOptions(
            # milliseconds
            timeout=settings.AGENT_TIMEOUT,
        ),
    ),
    tools=[
        AgentTool(query_agent),
        AgentTool(tax_agent),
        describe_table,
        explain_query,
        get_schema,
        sample_rows
    ],
    output_schema=ManagerResponse,
    planner=BuiltInPlanner(
        thinking_config=ThinkingConfig(
            include_thoughts=True, thinking_budget=settings.MANAGER_THINKING_BUDGET
        )
    ),
)

Expected behavior
A very small thought with minimal tokens and only necessary thinking.

Screenshots

Desktop (please complete the following information):

• OS: Linux
• Python version : 3.12
• ADK version(pip show google-adk): 1.15.1

Model Information:

• Are you using LiteLLM: No
• Which model is being used : gemini-2.5-flash

Additional context
Also, can you explain why are somethings in [] , like "[briefly describe the initial instinct]". Refer the second photo