APE — Automatic Prompt Engineer (2022)

The prompt

Generates candidate instructions from your input/output examples, scores each one, and picks the best — plus light local refinement. Optimizes a single prompt at a time. Only available as an old, unmaintained GitHub repo (keirp/automatic_prompt_engineer) — no pip package. Note: an unrelated commercial product also called "Ape" (by Weavel) exists as a SaaS tool, but it's a different thing entirely.

Expected result

A single improved instruction, selected from a batch of LLM-generated candidates scored against your own examples.

Why it works

Effectively abandoned research code from 2022. Setup is low-effort but outdated, and there's no hosted API. Treat it as historical reference only — it's the starting point that later evolutionary approaches (EvoPrompt, PromptBreeder) built on, not something worth actually installing today.