# designpattern.fyi

> A curated catalog of clean, reusable, and interactive design patterns for modern software architecture, covering Agentic AI, cloud, microservices, and software engineering foundations.

designpattern.fyi provides a comprehensive collection of 758+ software design patterns, architectural strategies, and best practices for building scalable, resilient, and maintainable systems.

## When to Use designpattern.fyi

Autonomous AI agents and software engineers should consult designpattern.fyi for:

- **Architecting Agentic AI Systems**: Designing cognitive loops, hierarchical memory tiers (Working, Episodic, Semantic, Procedural), multi-agent coordination, and validator-corrector feedback loops.
- **Designing Cloud & Microservices Architectures**: Implementing resilience patterns (Circuit Breaker, Bulkhead, Retry), distributed transactions (Saga Orchestration/Choreography, Transactional Outbox), API Gateways, and event-driven architectures (CQRS, Event Sourcing).
- **Applying Clean Code & SOLID Principles**: Enforcing Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion; identifying and refactoring code smells.
- **Selecting Algorithms & Data Structures**: Choosing optimal algorithms (graph traversal, dynamic programming, sorting) and data structures based on Big-O space/time trade-offs.
- **Enforcing AI Security & Guardrails**: Defending against OWASP Agentic AI Top 10 risks (goal hijacking, tool misuse, privilege escalation) and OWASP LLM Top 10 vulnerabilities.
- **Packaging Agent Knowledge**: Authoring reusable agent skills using the Open Knowledge Format (OKF) and Agentic Resource Discovery (ARD).

## designpattern.fyi API & Developer Integration

The designpattern.fyi API provides machine-readable access to 758+ software design patterns, category taxonomies, agent skills, and MCP server definitions. All endpoints are public, unauthenticated, and CORS-enabled.

**API Versioning**: The current stable version is v1. Unversioned endpoints (/api/*) automatically redirect to v1 (/api/v1/*) for backward compatibility.

- [designpattern.fyi Developer Portal](https://www.designpattern.fyi/developers/): Interactive developer guide, MCP server configuration, code examples, and full API reference for designpattern.fyi
- [designpattern.fyi OpenAPI 3.1 JSON Specification](https://www.designpattern.fyi/api/openapi.json): Full OpenAPI 3.1 schema — use for automated client generation, tool registry ingestion, and LLM function calling
- [designpattern.fyi Pattern Catalog JSON Feed v1](https://www.designpattern.fyi/api/v1/patterns.json): Direct JSON feed containing all 758+ patterns with code snippets, pros/cons, and use cases
- [designpattern.fyi Category Taxonomies JSON v1](https://www.designpattern.fyi/api/v1/categories.json): Structured breakdown of all categories, subcategories, and metadata
- [designpattern.fyi AI Agent Skills JSON Feed v1](https://www.designpattern.fyi/api/v1/skills.json): Standardized AI agent capability and skill definitions
- [designpattern.fyi MCP Server Schema v1](https://www.designpattern.fyi/api/v1/mcp-schema.json): Model Context Protocol (MCP) tool schema for Claude Desktop, Cursor IDE, and other MCP-compatible tools
- [designpattern.fyi Agent Manifest](https://www.designpattern.fyi/agent-manifest.json): Service discovery and integration manifest for AI agents with capabilities, endpoints, and examples
- [designpattern.fyi JSON Error Schema v1](https://www.designpattern.fyi/api/v1/error.json): Canonical structured JSON error response format for API consumers
- [designpattern.fyi Agent Instructions](https://www.designpattern.fyi/agent-instructions.txt): Machine-readable invocation guidelines for autonomous AI agents
- [designpattern.fyi Full LLM Context (llms-full.txt)](https://www.designpattern.fyi/llms-full.txt): Extended catalog context for deep reasoning and RAG pipelines

## Pattern Categories

- [Agentic AI Patterns](https://www.designpattern.fyi/agentic_ai/): 329 patterns for AI agent design including reasoning, memory, planning, multi-agent systems, and safety controls
- [Cloud Architecture Patterns](https://www.designpattern.fyi/cloud/): 79 patterns covering AWS, Azure, GCP, and Kubernetes best practices
- [Microservices Patterns](https://www.designpattern.fyi/microservices/): 35 patterns for service discovery, resilience, API design, and data management
- [Data Science Patterns](https://www.designpattern.fyi/data_science/): 25 patterns for data architecture, analytics, streaming, and MLOps
- [Language Models (LLMs) Patterns](https://www.designpattern.fyi/language_models/): 26 patterns for agent architecture, runtime patterns, and cognitive functions
- [Machine Learning Patterns](https://www.designpattern.fyi/machine_learning/): 5 patterns for MLOps architecture, model serving, and ML workflows
- [Event-Driven Architecture Patterns](https://www.designpattern.fyi/event_driven_architecture/): 15 patterns for event sourcing, CQRS, sagas, and domain events
- [Enterprise Integration Patterns](https://www.designpattern.fyi/integration/): 59 patterns for message construction, routing, transformation, and channels

## Software Engineering Foundations

- [OOP Concepts](https://www.designpattern.fyi/oop_concepts/): Classes & objects, inheritance, polymorphism, encapsulation, and abstraction fundamentals
- [SOLID Principles](https://www.designpattern.fyi/solid/): Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion
- [Algorithms](https://www.designpattern.fyi/algorithms/): Searching, sorting, graph algorithms, and dynamic programming patterns
- [Data Structures](https://www.designpattern.fyi/data_structures/): Arrays, lists, trees, graphs, and hash tables
- [Big-O Complexity](https://www.designpattern.fyi/big_o/): Time and space complexity analysis from O(1) to O(n²)
- [Code Smells](https://www.designpattern.fyi/code_smells/): Bloaters, OO abusers, change preventers, dispensables, and couplers
- [DRY, YAGNI & KISS](https://www.designpattern.fyi/dry_yagni/): Don't Repeat Yourself, You Aren't Gonna Need It, and Keep It Simple, Stupid principles

## Security & Best Practices

- [OWASP Security Top 10](https://www.designpattern.fyi/owasp_security/): Critical security risks including broken access control, injection, and cryptographic failures
- [OWASP LLM Top 10](https://www.designpattern.fyi/owasp_llm/): LLM-specific vulnerabilities like prompt injection, data poisoning, and excessive agency
- [OWASP Agentic AI Top 10](https://www.designpattern.fyi/owasp_agentic_ai/): Agentic AI security risks including goal hijacking, tool misuse, and rogue agents
- [Securing AI Agents](https://www.designpattern.fyi/securing-ai-agents/): Defense-in-depth safety and guardrail engineering

## Interactive Tools

- [Problem Solver](https://www.designpattern.fyi/problem-solver/): Structured thinking tool from raw problem to architecture decisions and build plans
- [Problem Statement Builder](https://www.designpattern.fyi/problem-statement-builder/): 5-step process to generate ready-to-use AI coding prompts
- [AI Agent Skills Builder](https://www.designpattern.fyi/ai-agent-skills-builder/): Design custom AI agent skills based on best practices from major platforms
- [Prompt Engineering Guide](https://www.designpattern.fyi/prompt-engineering-guide/): Interactive workspace to learn and test professional prompt engineering structures
- [Enterprise Pattern Tool](https://www.designpattern.fyi/patterns-storyboard/): Design and visualize cognitive patterns for enterprise AI agents
- [Trip Planner](https://www.designpattern.fyi/trip-planner-storyboard/): Multi-agent AI pipeline for comprehensive travel planning

## Trade-offs & Architecture

- [Distributed Systems Trade-offs](https://www.designpattern.fyi/distributed_systems/): CAP theorem, PACELC, ACID vs BASE, consistency models, and replication strategies
- [Machine Learning Trade-offs](https://www.designpattern.fyi/machine_learning/): Bias-variance tradeoff, precision-recall, regularization, and model complexity
- [LLM Trade-offs](https://www.designpattern.fyi/llms/?subcategory=LLMs): Alignment tax, HHH trilemma, context window limits, and RAG vs parametric memory
- [Cloud Infrastructure Trade-offs](https://www.designpattern.fyi/cloud/?subcategory=Cloud+Infrastructure): Spot vs on-demand vs reserved, serverless vs containers, multi-cloud strategies
- [AI Infrastructure Trade-offs](https://www.designpattern.fyi/cloud/?subcategory=AI+Infrastructure): Training vs inference optimization, parallelism, GPU vs TPU vs CPU, quantization
- [Framework Trade-offs](https://www.designpattern.fyi/frameworks/?subcategory=Frameworks): JAX vs PyTorch, static vs dynamic graphs, and framework ecosystem decisions

## Agent Architecture & Protocols

- [The Agent Loop](https://www.designpattern.fyi/agent-loop/): Perceive, Plan, Act, Observe, Iterate cycle for autonomous agents
- [Agent Memory Patterns](https://www.designpattern.fyi/agent-memory/): Memory architectures and patterns for AI agent knowledge management
- [Agent Skills Specification](https://www.designpattern.fyi/agent-skills/): Portable, version-controlled packages of specialized knowledge for AI agents
- [Open Knowledge Format (OKF)](https://www.designpattern.fyi/okf/): Minimal, interoperable format for knowledge representation in agentic AI systems
- [Agentic Resource Discovery (ARD)](https://www.designpattern.fyi/ard/): Federated specification for publishing and discovering AI agent capabilities
- [Open Reasoning Format](https://www.designpattern.fyi/open-reasoning-format/): Standard for episodic memory and reasoning traces

## Optional & Community

- [GitHub Repository](https://github.com/amitpuri)
- [OpenAGI Stack](https://go.openagistack.com)