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Features

AI coding agents are only as good as their input. SPECLAN gives you the framework to turn loose ideas into structured specifications that AI can actually act on — layered, traceable, Git-native, and built right into VS Code.

Layered Specifications

Structure requirements from business goals down to detailed requirements using a layered hierarchy: Goals, Features (with hierarchical Sub-Features), and Requirements. Features can nest to any depth, letting you decompose complex systems naturally. The hierarchy is flexible — start at any level and let AI fill in the rest.

G-001  Business Goal
  |- F-3012  Feature
    |- F-3013  Sub-Feature
      |- R-4821  Requirement
      |- R-4822  Requirement
    |- F-3014  Sub-Feature

Git-Native Workflow

Specifications live as Markdown files with YAML frontmatter, stored directly in your repository. Track changes with git diff, review specs in pull requests, branch for experiments, and merge when ready. No external database, no vendor lock-in, no syncing headaches. Your specs travel with your code — always in context, always versioned.

---
id: R-4821
type: requirement
status: approved
parent: F-3012
---
# User Authentication
The system **shall** authenticate
users via OAuth 2.0 before granting
access to protected resources.

AI-Powered Agents

Integrated AI agents — powered by Claude, Google Gemini, or OpenAI — generate, refine, and validate specifications on your behalf. Describe a feature in a sentence and watch the agent produce a full requirement tree. Agents also detect gaps, suggest improvements, and flag inconsistencies. You stay in control — every suggestion is a proposal, never an override.

Generate specs for "user login"
Created F-4010: User Login
Created F-4011: OAuth 2.0 Login
Created F-4012: Password Reset
Created R-7301: Authenticate via OAuth
Created R-7302: Handle invalid credentials
Created R-7303: Lock after failed attempts
Review and approve? (y/n)

VS Code Integration

A purpose-built extension with spec tree views, a WYSIWYG Markdown editor, status badges, and contextual actions. Create, navigate, and edit specifications without leaving your editor. Git status colors show which specs have changed, and the command palette gives you quick access to every operation. It feels like a native part of VS Code because it is.

Explorer
>SPECLAN: Goals
>User Managementapproved
>Authenticationreview
OAuth 2.0 Logindraft
Password Resetapproved
>Authorizationdraft

Full Traceability

Trace any requirement back through sub-features, features, and business goals. Bidirectional links mean you can also start at a goal and see every requirement that implements it. Traceability reports surface orphaned specs and incomplete chains. Know exactly why every line of code exists — and prove it.

R-4821Requirement
F-3013Sub-Feature
F-3012Feature
G-001Goal

Status Lifecycle

Move specifications through a formal lifecycle: draft, review, approved, in-development, and released. Status transitions enforce rules — you cannot approve a spec that still has draft children. Once a spec enters development, it is locked to prevent moving targets. When you need to change a spec in development or later, create a change request — it follows its own lifecycle and merges in the next sprint.

draft
review
approved
in-development
under-test
released
deprecated

Ready to Get Started?

Install the SPECLAN extension from the VS Code Marketplace and start structuring your specifications today.