AI Software Design Specification Generator
create architecture docs with AI-generated diagrams
Transform system descriptions into complete software design specifications. Auto-generate architecture diagrams, component designs, data models, and API specs in minutes using AI.
What is a Software Design Specification?
A Software Design Specification (SDS) is a technical document that describes the architecture, components, interfaces, and data flow of a software system. Unlike a PRD which defines what to build, an SDS defines how to build it. It includes system architecture diagrams, component designs, database schemas, API specifications, security requirements, and performance considerations.
Our AI SDS generator creates comprehensive design specifications from natural language system descriptions. Engineers and architects use it to document microservices, monolithic applications, APIs, and distributed systems. The tool automatically generates Mermaid architecture diagrams, suggests design patterns, and creates API documentation following industry best practices.
Software teams at tech companies, startups, and enterprises use design specifications to align engineering teams, facilitate code reviews, onboard new developers, and maintain system documentation as architectures evolve.
Generate design specs in 3 steps
Describe Your System
Explain your software architecture, components, data flow, and technical requirements. Choose from templates: Microservices, Monolith, Serverless, or API.
AI Generates SDS + Diagrams
AI creates complete design specification with auto-generated Mermaid diagrams, component designs, data models, API specs, and security considerations.
Export & Share
Download as Markdown, PDF, or sync to Confluence, Notion, or GitHub wiki. Diagrams export as editable Mermaid code or PNG images.
Pre-built templates for every architecture
Microservices
Distributed service architecture
Monolithic App
Traditional layered systems
Serverless
FaaS & event-driven
REST API
API-first design
Event-Driven
Message queues & pub/sub
Data Pipeline
ETL & data processing
Everything engineers need to document architecture
Auto-Generated Diagrams
AI creates Mermaid architecture diagrams including system context, component, sequence, and data flow diagrams automatically.
API Specification Generator
Generates OpenAPI/Swagger specs for REST APIs with endpoints, request/response schemas, and authentication details.
Data Model Design
Creates entity-relationship diagrams, database schemas, and data dictionaries with relationships and constraints.
Security Requirements
Auto-includes authentication, authorization, data encryption, and security best practices based on your system type.
Performance Specs
Defines latency requirements, throughput targets, scalability considerations, and caching strategies.
Version Control Ready
Export as Markdown for GitHub/GitLab wiki integration. Track spec changes alongside code in version control.
Common questions about software design specifications
When should I write a software design specification?
Write an SDS before starting implementation for any non-trivial system. This includes new microservices, major refactors, architecture changes, or systems with multiple components. The design phase helps identify technical challenges, choose appropriate patterns, and ensure team alignment before code is written. For simple features or bug fixes, lightweight documentation like technical tickets is usually sufficient.
What's the difference between high-level and low-level design?
High-level design (HLD) focuses on system architecture, component interactions, and technology choices. It answers “what services/modules exist and how do they communicate?” Low-level design (LLD) drills into implementation details like class diagrams, algorithms, and data structures. Our tool generates HLD by default, but you can configure it to include LLD sections for specific components.
How do I create architecture diagrams?
Our AI automatically generates Mermaid diagrams from your system description. Mermaid is a text-based diagramming language that's version-control friendly and renders in GitHub, GitLab, and most documentation tools. Common diagram types include: system context diagrams (how your system fits in the ecosystem), component diagrams (internal structure), sequence diagrams (request flow), and ER diagrams (data models). All diagrams are editable and exportable.
Should I use a design spec template or start from scratch?
Start with a template! Our templates (Microservices, Monolith, Serverless, API) provide proven structure and ensure you don't miss critical sections. Templates include architecture-specific patterns—for example, the Microservices template covers service discovery, inter-service communication, and distributed tracing, while the Serverless template focuses on function triggers, cold starts, and event-driven patterns. You can always customize after generation.
How detailed should my API specifications be?
API specs should be detailed enough that another engineer could implement the endpoints without asking questions. Include: HTTP methods, URL paths, request/response schemas (with field types and validation rules), authentication requirements, error responses, and rate limits. Our tool generates OpenAPI 3.0 compatible specs with JSON schema definitions, making them both human-readable and machine-parseable for code generation.
How do I keep design docs up to date?
Store design specs in version control (Git) alongside code so they're versioned together. Update the spec when making architectural changes, similar to updating code comments. Many teams require spec updates in pull requests for architectural changes. Export specs as Markdown and store in your repository's /docs folder or GitHub wiki. With WhisperCode Pro, you can auto-sync specs with your docs site and track spec changes in pull requests.
Frequently asked questions
Sick of writing design docs manually?
Use WhisperCode to turn your voice explanations into complete software design specifications with AI-generated architecture diagrams. Perfect for design reviews, team onboarding, and keeping documentation updated.
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