Skip to main content

Lab 4 Challenge: Structured Haiku & Sentiment Analysis

Goal​

Your task is to evolve your "Haiku Poet" agent into a "Structured Analyzer". Instead of returning plain text, the agent must now analyze the user's message and return a JSON object containing both a haiku and a sentiment analysis of the input.

Requirements​

  1. Navigate into your haiku_poet_agent directory (created by duplicating echo_agent).
  2. Define a Pydantic Schema: Create a class named HaikuAnalysis that defines two fields:
    • haiku: A string containing the 5-7-5 poem.
    • sentiment: A string (e.g., "positive", "negative", or "neutral").
  3. Update the Agent Configuration:
    • Set the output_schema to your HaikuAnalysis class.
    • Set the output_key to "last_analysis".
  4. Refine Instructions: Update the agent's instruction to ensure it understands it must now categorize the sentiment in addition to writing the haiku.
  5. Run and Verify: Run the agent using adk web haiku_poet_agent. In the Dev UI, verify that the response is a valid JSON object.
  6. Inspect State: After a few interactions, check the "Session State" in the Dev UI to confirm that "last_analysis" is being populated correctly.

Python Approach (Primary)​

Modify agent.py to include the Pydantic model and updated LlmAgent parameters.

from pydantic import BaseModel
from google.adk.agents import LlmAgent

# TODO: Define your Pydantic schema
class HaikuAnalysis(BaseModel):
    # TODO: Add fields
    pass

root_agent = LlmAgent(
    name="haiku_analyzer_agent",
    model="gemini-2.5-flash",
    instruction="...", # TODO: Update instructions for sentiment + haiku
    output_schema=...,  # TODO: Link the schema
    output_key=...      # TODO: Set the output key
)

Self-Reflection Questions​

  • Why is it better to use output_schema instead of just asking the LLM to "respond in JSON" in the text instructions?
  • What happened to the agent's ability to use tools once you enabled output_schema? Why does the ADK enforce this restriction?
  • Look at the Dev UI's "Session State". How could another agent in a future multi-agent system use the data stored in the "last_analysis" key?

🕵️ Hidden Solution 🕵️​

Looking for the solution? Here's a hint (Base64 decode me): L2RvYy1hZGstdHJhaW5pbmcvbW9kdWxlMDQtbGxtYWdlbnQtZGVlcC1kaXZlL2xhYi1zb2x1dGlvbg==

The direct link is: Lab Solution