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    Anthropic Claude Certified Associate – Foundations (CCAO-F)· Lessons

    Domain 4 · Lesson 17/30

    Developing and iterating with Claude: plan, verify, judge, refine

    Use Claude to support solution design, development, and iteration

    8 min read
    3.2% of exam
    7 sources
    Published 4 Oct 2026
    Docs as of 30 Sep 2026

    What you will be able to do

    • Sequence Claude-assisted development as explore, plan, implement, commit, and review the plan before anything changes
    • Turn vague requests into requests that include a check Claude can run, and recognise verification loops
    • Judge Claude's output beyond whether it works, using user testing and the five discernment lenses
    • Iterate in small, measurable steps so a regression can be traced to the change that caused it

    1.Plan before Claude changes anything

    When it is time to build, Anthropic's guidance for Claude Code describes four phases. First Claude explores the existing material until it understands the current setup. Next it plans: it works out what needs to change and writes a plan. Then it implements that plan, writes tests and fixes any failures. Last, the change is committed with a clear description.

    The planning phase is where you keep control. In Plan mode, Claude explores and proposes a plan without editing your files, so you review the approach before anything changes. This is the cheapest point to catch a misunderstanding. Correcting a plan takes one message. Unpicking a finished build that went in the wrong direction takes much longer.

    Checkpoint 1 of 6· Put it in order

    Put the phases of a Claude-assisted build in the order the best-practices guide recommends.

    1. 1.Explore: Claude reads the relevant material and learns how things work now
    2. 2.Implement: Claude builds from the plan, writes tests and fixes failures
    3. 3.Commit: the change is recorded with a descriptive message
    4. 4.Plan: Claude identifies what needs to change and writes a plan

    Sources12

    2.Give Claude a check it can run

    The definition of done you wrote at design time pays off here. Most weak requests to Claude are missing a check. Anthropic's best-practices guide shows the same tasks written with and without a verification criterion:

    Vague requests compared with requests that tell Claude how to verify the result (from Claude Code best practices)
    StrategyBeforeAfter
    Provide verification criteriaimplement a function that validates email addresseswrite a validateEmail function, with example test cases, then run the tests after implementing
    Verify UI changes visuallymake the dashboard look betterimplement this design from a screenshot, screenshot the result, compare, list differences and fix them
    Address root causes, not symptomsthe build is failingpaste the error, fix it, verify the build succeeds, and do not suppress the error

    In every row, the improved request asks Claude to run the check and keep working until it passes, all in the same message. Anthropic calls this a verification loop: Claude checks its own work and attempts to fix whatever fails. Any check you find yourself doing by hand over and over is a candidate for one of these loops. For higher stakes, use a second opinion: a fresh model tries to refute the result, so the agent that did the work is not also the one grading it.

    Checkpoint 2 of 6· Check yourself

    A team keeps asking Claude to "make the weekly status report better" and gets inconsistent results. Which change to the request will help most?

    Checkpoint 3 of 6· Exam question

    A project lead is demonstrating a new Claude-assisted reporting workflow to executives who could fund its wider use. What should the demonstration make clear alongside the benefits?

    Sources34

    3.Judge the result, not just whether it runs

    Passing its checks does not make a result good. The AI Fluency course for builders warns that Claude's default output is often technically complete but misses the point. AI also has predictable blind spots: concurrency, security, and anything that only breaks at scale. The course gives five lenses for judging AI-generated work: correctness, quality, fit, experience and responsibility.

    The most revealing test is a real user. Hand your build to someone playing the user, and do not explain it or help them. Watch where they get confused, what they ignore, and what they wanted that you never built.

    Now compare the two signals. If the tests pass and the user is happy, you are on track. If the tests pass but the user is unhappy, the build is not at fault. You described the wrong intent. Go back up the Description Chain to the link that broke, whether that is the requirement or the spec, before you ask Claude for another version.

    Checkpoint 4 of 6· Check yourself

    A Claude-built intake form passes every acceptance test, but pilot users keep abandoning it halfway. What does this most likely tell you?

    Sources5

    4.Iterate in small, measurable steps

    Iteration means changing something, checking whether it helped, and keeping or reverting it. That only works if each change is small enough to evaluate on its own. Anthropic's workflow guidance says to make changes in small, testable increments and to verify each one. It also says to fix root causes rather than suppress symptoms.

    The same discipline applies to prompts and to Claude-assisted processes. Anthropic's classification cookbook lists two practices that matter once a system is in use. Regression detection makes sure a prompt change has not quietly hurt accuracy. Version control tracks performance over time as the system evolves. Put these together with the acceptance statements from your design phase and you get a working rhythm. Make one change. Measure it against the same criteria as before. Record the result. Then decide.

    If several changes ship together and quality drops, there is no way to tell which change caused the drop. And if the original criteria were never written down, there is nothing to compare the new version against.

    Checkpoint 5 of 6· Check yourself

    A team wants to make three improvements to its Claude-assisted proposal process: a new prompt, a new template and an extra review step. What is the soundest way to roll them out?

    Checkpoint 6 of 6· Exam question

    In a pilot of a new Claude-assisted briefing arrangement, three of eight testers report that the output is "not quite right" but say nothing more specific. What should the pilot's owner do first?

    Sources26

    Exam traps

    Each one states something that sounds right. Open it to see what is actually true.

    1. 1.If every acceptance test passes, the solution is done.Why is that wrong?

      Tests only check the intent you described. If users are unhappy even though the tests pass, the description was wrong and you need to revisit it upstream.

      Covered in Judge the result, not just whether it runs

    2. 2.Bundling several fixes into one revision is the fastest way to improve a Claude-assisted process.Why is that wrong?

      Changes should go in as small, testable increments so that any regression can be traced to the change that caused it.

      Covered in Iterate in small, measurable steps

    Sources

    Every claim above is drawn from one of these pages, quoted as it was written on the date shown.

    1. 1.
      “Plan: Claude explores and proposes a plan without editing your source files”
      ↩︎ Plan before Claude changes anything
    2. 2.
      “Plan before editing to review changes before they touch disk”
      ↩︎ Plan before Claude changes anything
      “Do refactoring in small, testable increments”
      ↩︎ Iterate in small, measurable steps
      “Do refactoring in small, testable increments”
      ↩︎ Exam trap 2
    3. 3.
      “has a fresh model try to refute the result”
      ↩︎ Give Claude a check it can run
      “In one prompt: ask Claude to run the check and iterate in the same message”
      ↩︎ Checkpoint
    4. 4.
      “a verification loop is an iterative process where Claude checks and attempts to fix the work.”
      ↩︎ Give Claude a check it can run
      “Anything you keep having to enforce by hand as a manual check qualifies for capture as a loop.”
      ↩︎ Give Claude a check it can run
    5. 5.
      “Code that runs can still fail. The default AI output is technically complete but often misses the point.”
      ↩︎ Judge the result, not just whether it runs
      “Evaluate AI-generated work across five lenses: correctness, quality, fit, experience, and responsibility”
      ↩︎ Judge the result, not just whether it runs
      “Watch where they get confused, what they ignore, and what they wanted that you never built.”
      ↩︎ Judge the result, not just whether it runs
    6. 6.
      “Regression detection: Ensuring prompt changes don't accidentally hurt accuracy”
      ↩︎ Iterate in small, measurable steps
      “Version control: Tracking prompt performance over time as your system evolves”
      ↩︎ Iterate in small, measurable steps

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