How to use AI coding agents with PRDs

How do you use AI coding agents with PRDs?

Use a PRD with an AI coding agent by turning product intent into scoped stories, acceptance criteria, constraints, and review checkpoints before implementation starts. In Hal, that means planning the requirement, validating the resulting work units, running a bounded loop, and reviewing output before merge.

Prerequisites

• A repository under version control.
• A small product change or feature idea.
• Access to a supported coding engine such as Codex, Claude Code, or Pi.
• A willingness to review generated code before merging.

Step 1: Write the smallest useful PRD

Include:

• user or operator affected by the change
• desired behavior
• in-scope and out-of-scope work
• constraints such as auth, data, performance, or UI rules
• acceptance criteria
• review notes and risky files

If the requirement is still vague, use the PRD readiness checker or AI coding PRD generator before implementation.

Step 2: Plan and validate in Hal

Use the documented Hal flow as the reviewable boundary:

hal plan "describe the product change"
hal convert
hal validate

Review the generated plan or story output. Do not continue if stories are too broad, criteria are untestable, or constraints are missing.

Step 3: Run one bounded implementation loop

hal run

Start with one story or one narrow requirement. The goal is to create output that can be reviewed in one sitting, not to hand over a broad roadmap.

Step 4: Review before merge

Inspect changed files, commits, reports, tests, unresolved criteria, and unexpected edits. If the output is partially correct, keep only what you can verify and rerun a smaller loop if needed.

PRD checklist for agent work

PRD section	Why it matters for agents
Scope	Prevents broad diffs and invented work.
Non-goals	Tells the agent what not to touch.
Acceptance criteria	Gives reviewers observable checks.
Constraints	Carries local product and technical rules.
Review plan	Makes the human checkpoint explicit.

Verification and no-guarantees rule

Before adopting Hal, verify the current source repository, install guide, release notes, and engine support. Hal structures coding loops; it does not guarantee correctness or replace developer review.