A field guideAI ENGINEERING 01 / 2026

A presentation for humans who ship

AI for
dummies.

You do not need an army of models. You need a system: one mind to frame the work, several hands to execute it, and a clean boundary between every task.

RULE ZEROStrong model for ambiguity.
Light model for bounded work.
ORCHESTRATOR

Decides what
needs to happen.

Opus / reasoning
UIComponent and visual statesagent/ui
TESTAcceptance casesagent/tests
DOCSGuide and examplesagent/docs

The orchestrator preserves intent, writes small contracts, and gathers results that can be verified. It does not need to type every line.

The subagent loop

Click a phase.
See the handoff.

Delegation means moving one bounded task into a smaller context—not giving away responsibility.

PackageContainsWhy it matters
Briefgoal, files, boundariesstops the worker inventing the problem
Worktreebranch and isolated checkoutparallel edits do not collide
Checkstests, build, criteriaturns “looks good” into evidence
Diffsmall, reviewable changeintegration and discard stay cheap

Git worktrees

One branch
per hand.

A worktree is another directory linked to the same repository. Each agent gets its own checkout and index; history remains shared.

git worktree add ../task-ui -b agent/ui · git worktree add ../task-tests -b agent/tests · git worktree list
REPOSITORYmainshared history
UIagent/uiisolated checkout
TESTagent/testsisolated checkout
DOCSagent/docsisolated checkout

Model routing

Do not pay for
reasoning where
you need rhythm.

WorkProfilePrompt shape
Planstrong / broadWhat changes? What can break?
Buildfast / focusedImplement this slice. Run these checks.
Exploreread-only / lightFind where this contract is used.
ReviewindependentDoes the diff satisfy the brief?

Skills

Write the right way
once.

A skill is a reusable procedure. It can carry instructions, references, scripts, and assets. It is not magical memory, and it does not replace acceptance criteria.

SKILL PACKAGE
SKILL.mdprocedure and limits
references/facts to consult
scripts/repeatable checks
assets/templates and examples
name: review-ui · check focus, mobile, reduced motion · run verification · return evidence

Based on Claude Code, Codex, Git, and agent-workflow research. Open the reference bundle →