skills.rest
MileniumTick
MileniumTickCOMMUNITY
Explore all skills by this author →
GitHub

sdd-spec

Write delta specs with Given/When/Then scenarios and ADDED/MODIFIED/REMOVED blocks.

Updated Mar 25, 2026
Search Tags:#specification#exploration#scenarios#acceptance-criteria#given-when-then#delta-spec
One-click install
npx skills add https://github.com/MileniumTick/skills --skill sdd-spec-mileniumtick
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: sdd-spec
Source: https://github.com/MileniumTick/skills/tree/main/skills/sdd-workflow/skills/sdd-spec
Command: npx skills add https://github.com/MileniumTick/skills --skill sdd-spec-mileniumtick

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Delta specs provide a precise, repeatable way to specify WHAT a change must do, converting exploration findings into actionable guidance for implementation.

Core Features & Use Cases

  • Structured delta blocks: Capture ADDED, MODIFIED, and REMOVED items as scenario-based Given/When/Then.
  • Acceptance criteria guidance: Define concrete success criteria to drive validation and testing.
  • End-to-end workflow support: From exploration approval to spec delivery, ensuring alignment across teams.

Quick Start

Provide the change-name in the Spec header and write delta scenarios using Given/When/Then to specify expected behavior.

Frequently Asked Questions about sdd-spec

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
What is a delta spec and when do I need Given/When/Then scenarios for software changes?▼

A delta spec defines exactly what a software change must do by capturing ADDED, MODIFIED, and REMOVED items. You need Given/When/Then scenarios when converting exploration findings into actionable, testable implementation guidance.

How do I write acceptance criteria for exploration-driven software changes?▼

You write acceptance criteria by defining concrete success criteria within delta spec blocks. Using Given/When/Then scenarios, specify the expected behavior for ADDED, MODIFIED, and REMOVED items to drive validation and testing.

How do I structure delta blocks for ADDED, MODIFIED, and REMOVED functionality?▼

Structure delta blocks by categorizing changes into ADDED, MODIFIED, and REMOVED sections. Within each block, use Given/When/Then scenarios to formally specify the expected behavior and acceptance criteria for the software change.

What is the best way to specify software modifications for team alignment?▼

The best way to specify software modifications is using delta specs with Given/When/Then scenarios. This structured approach translates exploration findings into formal result contracts, ensuring alignment across teams from spec delivery to implementation.

Can I use delta specs to define both new features and removed items?▼

Yes, delta specs explicitly handle both new features and removed items through ADDED and REMOVED blocks. Each block uses Given/When/Then scenarios to specify expected behavior and acceptance criteria for the software change.

Do I need a specific format to define what a software change must do?▼

Yes, defining a software change requires a formal result contract format. Delta specs satisfy this requirement by using a Spec header, Given/When/Then scenarios, and structured ADDED, MODIFIED, and REMOVED delta blocks.

Related Skills

Explore More Software Engineering Skills→
arestivoarestivo

openspec-verify-change

Verify software changes against specs, tasks, and design artifacts using the openspec CLI.

Community
Advanced
SQDR2SQDR2

openspec-sync-specs

Merge delta specifications into main specs by applying ADDED, MODIFIED, REMOVED, and RENAMED blocks.

Community
Advanced
AsiaOstrichAsiaOstrich
70

bdd

Guides the end-to-end workflow for writing and implementing Gherkin-based tests.

Community
Intermediate
f-esquivelf-esquivel

spec

Generates formal specification documents for software changes from a prompt.

Community
Advanced