Run a PRD-driven coding loop with Hal

Prerequisites

Install Hal first:

brew tap j-yw/tap && brew install --cask hal

Use Hal in a repository where you want product requirements to drive a sequence of coding-agent implementation iterations.

Manual workflow

hal init
hal plan
hal convert
hal validate
hal run

What each step does

• hal init creates the project workflow files.
• hal plan generates or captures a PRD.
• hal convert turns markdown requirements into structured runtime state.
• hal validate checks the workflow quality before execution.
• hal run executes implementation iterations.

When to use the loop

Use this workflow when a feature has multiple steps, when you want the coding agent to work from product requirements, and when every iteration should leave behind reviewable state.

Troubleshooting

• If Hal is unavailable after install, open a new terminal session.
• If validation fails, fix the PRD or structured state before running the coding loop.
• If a coding agent output is not acceptable, review the iteration artifacts before continuing.