agent-rules-books

<div align="center"> <img src="books-ai-rules.png" alt="AI agent rules from programming books" /> <h1 align="center">AI agents Rules / Skills from<br />Programming Books v0.5</h1> <p align="center"> <strong>AGENTS.md rules</strong> / <strong>skills</strong> for <strong>Codex</strong>, <strong>Cursor</strong>, <strong>Claude Code</strong>, distilled from classic <strong>software engineering books</strong> about refactoring, architecture, DDD and code quality. </p> <p align="center"> <a href="#about">About</a> · <a href="#release-matrix">Rules / Skills</a> · <a href="#books-list">Books List</a> · <a href="docs/USAGE.md">Usage</a> · <a href="docs/COMPATIBILITY.md">Books Compatibility</a> </p> </div>

About

MIT licensed universal project rules for coding agents.

This repository contains ready-to-use rule sets inspired by well-known books on software design, architecture, refactoring, legacy code, reliability, and data-intensive systems.

For editor-specific setup in Codex, Claude Code, and Cursor, see USAGE.md. It covers always-on vs on-demand usage, skills, scoped rules, MCP or RAG patterns, and the preferred setup for each editor.

Each rule set is released in three tool-agnostic Markdown versions:

• mini: the recommended version for most real task use
• nano: the compact fallback for very tight context budgets
• full: the canonical complete source and reference version

For constructive criticism from Reddit, see CRITICISM.md.

For release history, see CHANGELOG.md.

Release Matrix

Metrics:

• lines: physical line count from wc -l
• rules: Markdown list items counted with the deterministic release convention
• size: raw bytes from wc -c

| Rule Set | Full file | Full lines | Full rules | Full size | Mini file | Mini lines | Mini rules | Mini size | Nano file | Nano lines | Nano rules | Nano size | | --- | --- | ---: | ---: | ---: | --- | ---: | ---: | ---: | --- | ---: | ---: | ---: | | A Philosophy of Software Design | full | 370 | 177 | 13561 B | mini | 46 | 28 | 5774 B | nano | 35 | 17 | 2258 B | | Clean Architecture | full | 515 | 289 | 17782 B | mini | 49 | 31 | 5486 B | nano | 36 | 18 | 2254 B | | Clean Code | full | 297 | 220 | 13851 B | mini | 47 | 29 | 3804 B | nano | 32 | 14 | 1235 B | | Code Complete | full | 354 | 180 | 12407 B | mini | 56 | 38 | 6717 B | nano | 41 | 23 | 2544 B | | Designing Data-Intensive Applications | full | 393 | 205 | 16084 B | mini | 55 | 37 | 6949 B | nano | 34 | 16 | 2575 B | | Domain-Driven Design | full | 979 | 523 | 42424 B | mini | 48 | 30 | 5683 B | nano | 39 | 21 | 2266 B | | Domain-Driven Design Distilled | full | 317 | 158 | 11351 B | mini | 56 | 38 | 6438 B | nano | 41 | 23 | 2535 B | | Implementing Domain-Driven Design | full | 337 | 177 | 12848 B | mini | 57 | 39 | 7333 B | nano | 37 | 19 | 2723 B | | Patterns of Enterprise Application Architecture | full | 404 | 196 | 15501 B | mini | 54 | 36 | 8099 B | nano | 35 | 17 | 2823 B | | Refactoring | full | 433 | 242 | 17866 B | mini | 49 | 31 | 5167 B | nano | 37 | 19 | 1986 B | | Release It! | full | 382 | 204 | 13542 B | mini | 48 | 30 | 6372 B | nano | 38 | 20 | 2205 B | | The Pragmatic Programmer | full | 359 | 179 | 13398 B | mini | 65 | 47 | 7165 B | nano | 44 | 26 | 2263 B | | Working Effectively with Legacy Code | full | 371 | 193 | 13817 B | mini | 50 | 32 | 5707 B | nano | 35 | 17 | 1792 B | | Refactoring.Guru | full | 765 | 478 | 62561 B | mini | 64 | 46 | 6287 B | nano | 41 | 23 | 2593 B |

Books List

A Philosophy of Software Design

Author: John Ousterhout

The book focuses on fighting complexity through deep modules, simple interfaces, information hiding, and design choices that reduce cognitive load. This rule set is especially useful for API design, module design, and refactoring shallow abstractions.

Clean Architecture

Author: Robert C. Martin

The book describes designing systems around stable boundaries, the dependency rule, and the separation of business policies from details such as frameworks, databases, and UI. This rule set helps keep code resistant to technology churn.

Clean Code

Author: Robert C. Martin

The book focuses on readability, naming, small functions, responsibilities, tests, and simplicity. This rule set is a strong default for everyday coding and code review.

Code Complete

Author: Steve McConnell

The book covers a broad range of software construction practices: routine design, variables, classes, control flow, defensive programming, coding standards, and testing. This rule set helps agents make disciplined implementation decisions.

Designing Data-Intensive Applications

Author: Martin Kleppmann

The book covers reliability, scalability, consistency, replication, partitioning, transactions, data streams, and schema evolution. This rule set is intended for systems where data ownership, event flows, and consistency semantics matter.

Domain-Driven Design

Author: Eric Evans

The book introduces domain modeling, ubiquitous language, bounded contexts, tactical patterns, and strategic design. This rule set helps agents think in terms of the business model rather than tables, controllers, or DTOs.

Domain-Driven Design Distilled

Author: Vaughn Vernon

The book is a short, practical introduction to DDD. It focuses on subdomains, bounded contexts, context mapping, and basic tactical patterns. This rule set is a good fit when you want the benefits of DDD without excessive ceremony.

Implementing Domain-Driven Design

Author: Vaughn Vernon

The book shows how to apply DDD in real systems: aggregates, domain events, contexts, integrations, and application architecture. This rule set is more implementation-focused than domain-driven-design-distilled.

Patterns of Enterprise Application Architecture

Author: Martin Fowler

The book catalogues enterprise application patterns: layers, service layer, transaction script, domain model, data mapper, repository, unit of work, identity map, DTO, and integration patterns. This rule set helps choose an appropriate pattern instead of mixing responsibilities accidentally.

Refactoring

Author: Martin Fowler

The book describes safe ways to improve code structure without changing observable behavior. This rule set emphasizes small steps, tests, code smell detection, and keeping refactoring separate from feature changes.

Refactoring.Guru

Source: Refactoring.Guru

The site provides a practical refactoring process, code smell catalog, and catalog of refactoring techniques. This rule set is useful when an agent needs to diagnose smells, choose a safe treatment, preserve behavior, and stop before cleanup turns into uncontrolled redesign.

Release It!

Author: Michael T. Nygard

The book focuses on systems that survive production reality: failures, overload, timeouts, retries, circuit breakers, bulkheads, backpressure, observability, and deployment behavior. This rule set is useful for services, APIs, queues, integrations, and critical production paths.

The Pragmatic Programmer

Authors: Andrew Hunt, David Thomas

The book describes a pragmatic approach to software development: responsibility, DRY at the knowledge level, orthogonality, automation, fast feedback, prototyping, and adaptability. This rule set works well as a general engineering layer.

Working Effectively with Legacy Code

Author: Michael Feathers

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