AI仕様駆動開発: AIエージェント開発の新常識 (“AI spec-driven development: the new common sense of AI agent development”) is a Japanese technical book by 岡崎 太, published as a Kindle-only title in the AI Zamurai Tech Series. It gives a compact, systematic account of the spec-driven approach to development with AI agents — what role a specification plays when an agent writes the code, and the practical steps for working that way — and, as one title in that series, it limits itself to material directly applicable to practice.
A review of the book on note.com places it in the wave of interest in Spec-driven development that followed Amazon’s announcement of Kiro and the “80% design, 20% development” approach that KDDI-affiliated KAG brought into practice in the second half of 2025.
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According to the review, the theme running through the book is a division of labour in writing the specification itself: the human thinks through the core of the requirements, and the AI fleshes out the specification around them, so that writing a specification becomes a joint task with the AI. The reviewer singles out the book’s point that an AI writes far better code from a clear specification than from a vague instruction — a matter, in the reviewer’s reading, of how the input is structured rather than of model capability, because tacit knowledge in a person’s head has to be externalized as a specification before the AI can use it.
The reviewer also credits the book with lowering the entry barrier for engineers who do not know what to put in a specification, while noting that basic design skill still has to be developed separately, and describes what a reader takes away as a concrete picture of the order in which to work on the next project rather than a body of theory.