improve-prompt

Review and rewrite prompts, system prompts, agent instructions, CLAUDE.md files, and Claude Code skills against Anthropic's prompt-engineering guidance and the Karpathy coding-behaviour principles. Diagnoses the artifact with a structured rubric (clarity, examples, XML structure, output format, hallucination guards, consistency, guardrails, token weight, rule craft, and — for skills — trigger description quality and progressive disclosure), then delivers a surgical rewrite with per-change rationale. Bundles the full Anthropic prompting docs (best practices, Opus 4.8 guide, guardrail guides, four production use-case guides) and the Karpathy material three ways: the guidelines verbatim, worked before/after examples, and a prompt-craft dissection (karpathy-prompt-craft.md) that treats the guidelines as a model of rule-writing — principle anatomy (name, bold directive, checkable behaviour bullets, self-test), tradeoff clauses, imperative-to-verifiable transforms, ownership-scoped cleanup, working-if success signals, a cross-surface reuse pattern (one canonical rule text wrapped per surface), and a mergeable hardening block — which the skill applies to every prompt it improves.