# Exercise 03: Design for the Loop
**Concept:** The Agent Loop (CC-001)
**Level:** Advanced
**Time:** ~20 minutes
---
## Objective
Design a multi-step task that takes advantage of the agent loop's
strengths. You will write a prompt that requires Claude to gather
information from multiple sources, make decisions based on what it
finds, and produce a structured output.
This exercise has no step-by-step walkthrough. You get a scenario,
constraints, and success criteria. How you get there is up to you.
---
## Before You Start
Confirm you have:
- [ ] Completed Exercises 01 and 02
- [ ] Claude Code open in this directory
- [ ] Internet access (Claude will use WebSearch)
---
## The Scenario
You want to evaluate whether a specific open-source tool is worth
adopting for your workflow. Instead of spending an hour researching
manually, you will write one prompt that makes Claude do the research
for you.
## Your Task
Write a prompt that makes Claude:
1. **Search** for information about a tool you are curious about
(pick any real tool: a CLI tool, a library, a framework)
2. **Read** the tool's documentation or README
3. **Compare** it against an alternative you already know
4. **Write** a structured evaluation to a file called `evaluation.md`
The evaluation file must include:
- Tool name and what it does (one sentence)
- Three strengths
- Three weaknesses or limitations
- A direct comparison with the alternative
- A verdict: adopt, wait, or skip
## Constraints
- Your prompt must be a single message (no back-and-forth)
- Do not tell Claude which tools to use (let the loop decide)
- The output must be a single file, not multiple files
- Use Plan Mode first to preview, then execute
## Success Criteria
- [ ] Claude made at least 5 tool calls to complete the task
- [ ] The evaluation file exists and contains all required sections
- [ ] The strengths and weaknesses are specific (not generic praise)
- [ ] The comparison is direct, not just two separate descriptions
- [ ] The verdict gives a clear recommendation with reasoning
---
## Hints (only if stuck)
Hint 1: Prompt structure
A good prompt for the agent loop includes:
- What to research (specific tool name)
- What to compare against (specific alternative)
- What output to produce (file name and structure)
- What NOT to do (no installation, no code generation)
Hint 2: Example prompt skeleton
```
Research [tool X] and compare it to [tool Y] for [use case].
Search the web for recent reviews and the official docs.
Write an evaluation to evaluation.md with:
- One-sentence description of each tool
- 3 specific strengths of [tool X]
- 3 specific weaknesses of [tool X]
- Direct comparison table: [tool X] vs [tool Y]
- Verdict: adopt, wait, or skip, with reasoning
Do not install anything. Do not write code. Research only.
```
---
## Reflection
After completing this exercise, consider:
- How many tool calls did Claude make? (Check the terminal output)
- Did the loop take any detours? Were they useful or wasteful?
- What would you change in your prompt to get a better result?
- How long would this research have taken you manually?
The agent loop is most powerful when the task requires gathering
and synthesizing information from multiple sources. A single prompt
replaces what used to be 30 minutes of tab-switching and note-taking.
---
## What You Learned
- **Single-prompt, multi-step tasks** are where the agent loop shines
- **Output structure in the prompt** gives the loop a clear target
- **Plan Mode first** lets you verify the approach before committing
- **The loop handles the how:** You specify the what and the where
---
## Clean Up
```bash
rm evaluation.md
```
---
## What Comes Next
You now understand the agent loop: what it is (Exercise 01), how to
control it (Exercise 02), and how to design tasks for it (Exercise 03).
Next concepts to explore:
- **CC-002 Built-in Tools** - The specific tools the loop uses
- **CC-010 CLAUDE.md** - How to give the loop standing instructions
- **CC-006 Permissions** - How to control what the loop is allowed to do