🧪Lesson 08AI Engineer Loopcraft Workshop 2026

Compare a candidate check beside the current check

Use the same event file and check command while a small TypeScript candidate check says the next state and reason. The current checker still decides.

Use the same event file and check command from earlier lessons. First add a plain TypeScript candidate check that returns the next state and reason for one issue. Then compare its answer with the current checker: the current checker still decides, and any mismatch stops here.

Your next move

You already have

The current checker, event file, check command, status output, dispatch receipts, and read-only review path.
Enough evidence to compare a new decision path without letting it drive the loop.

Add now

A plain TypeScript candidate check that returns the next state and reason for one issue event.
A compare command that runs the current checker and candidate check against the same input.
One normal comparison receipt and one recovery drill receipt.

Stop before

Replacing the current checker with the candidate check.
Letting the candidate write to GitHub, APIs, product files, timers, or parallel worktrees.
Moving past a mismatch without explaining it.

Tiny compare-only receipt shape

mode: compare-only
inputEvent: ISSUE-001 ready
currentDecision: ready -> dry-run claim allowed
candidateDecision: ready -> dry-run claim allowed
agreement: yes
currentCheckerStillInCharge: true
recoveryDrill: stale claim -> stopped with reason

Starter prompt

Use the event file and check command from earlier lessons. Add a plain TypeScript candidate check that returns the next state and reason for one issue. Run it beside the current checker as a compare-only check. Save a receipt with inputEvent, currentDecision, candidateDecision, agreement, reason, current checker still in charge, and one stale/failed/interrupted recovery case. Do not let the candidate check write to GitHub, APIs, product files, timers, or parallel worktrees yet.

Build checklist

0/4 done

Write the candidate check

Start with plain TypeScript data or one function, not a library. Name the events it accepts, then return next state and reason.

Compare beside the current checker

Use the same event file and check command. Keep the current checker in charge; the candidate answer is for comparison only.

Record agreement or mismatch

Write a receipt that includes inputEvent, currentDecision, candidateDecision, agreement, reason, and current checker still in charge.

Drill recovery

Simulate stale, failed, or interrupted work and show the next state, reason, and stop message.

Proof to save

Save proof that the candidate check matches one normal decision and one recovery case without taking over.

A plain TypeScript function, data table, or transition table returns the next state and reason from one issue event.
The compare command runs the current checker and candidate check against the same input.
A compare-only receipt shows inputEvent, currentDecision, candidateDecision, agreement, reason, and current checker still in charge.
One recovery drill proves stale, running, failed, or interrupted work stops with a reason.

mode: compare-only; current checker stays in charge
inputEvent: event or issue inspected
currentDecision: current checker result
candidateDecision: candidate check result
agreement: yes / no plus reason
recoveryDrill: scenario and result
nextAction: keep comparing, fix mismatch, or promote later

Done when

One compare-only receipt shows the current checker and candidate check agree for a normal issue, and one recovery receipt shows stale, failed, or interrupted work stops safely.

Why it matters

Risk reduced: the candidate decision is visible before it can decide anything.
Temptation avoided: swapping in a new controller before its answers match the current checker.
Do not automate yet: parallel worktrees, timers, provider switching, or real reviewer launches.

Try this 🔨

For one issue, name the event read, the current checker decision, and the candidate check decision.

Exploration prompts

Use these when you want to ask an agent for a narrower pass instead of handing it the whole lesson.

Name the candidate check

List the events, checks, actions, command, and receipt path. Start with a TypeScript table or function, then say which current checker code remains in charge.

Compare decisions

Run or simulate one issue through the current checker and the candidate check. Write a comparison table: input, currentDecision, candidateDecision, agreement, reason, and receipt path.

Practice recovery

Pick one bad state: stale claim, failed check, interrupted run, or missing receipt. Describe the recovery event, next safe action, stop message, and proof that the checker stopped safely.