ACI-008: The Prompt That Worked

Thesis

The quality of a task definition shapes the quality of agentic output. A good definition asks a question, fences the purpose as well as the features, and checks its dependencies before the work starts. A definition that asks for an outcome, such as parity with an existing application, gives neither you nor the agent a test for when the work is done or when it has become a different job.

Story

Laksa, a CMS built with Elixir, Phoenix and Ash, began on 14 July 2025 as a port of Postcard, a Rails personal website builder (Laksa@8433c8d39, 2025-07-14). By 31 March 2026 it had completed 48 steel threads (Laksa@c22d5c6d4, 2026-03-31). A steel thread is the project's written definition of one unit of work, the document the human and the agent work from; ACI-020: Steel Threads Beat Feature Branches teaches the method at 2xx. Three early threads show how a definition shapes what gets built.