# Spec Driven Development — Front-Matter: Front matter (cover, title, contents) - **Source**: /library/Spec Driven Development/source-file.pdf - **PDF pages**: 1–10 - **Pages without text**: 1 --- Spec Driven Development J.C. Ködel Spec Driven Development 1. About the author 2. 0 - Why SDD is essential in the age of AI 1. The thesis: knowledge and specification are leverage 2. The three arguments: judge, decide, answer 3. The 70% and the 30% 4. What SDD is, in plain language 5. SDD is not exactly new 6. The next step 3. 0b - Trilogy map: what lives in each volume 4. 1 - Fundamentals: where SDD comes from 1. Waterfall: the right instinct, the wrong cost 2. The agile turn: learning to iterate cheaply 3. Scrum, the pillar; XP and Kanban, the support 4. What each method taught us 5. SDD: the synthesis that only now became viable 6. Why AI needs specification 7. The cycle, now with a name 8. The next step 5. 2 - Anatomy of a specification 1. From vague intent to a blueprint 2. What a spec is (and what it isn't) 3. The why part: problem and intent 4. The scope part: in, out, and non-goals 5. The behavior part: scenarios, rules, and acceptance criteria 6. The edges: exceptions, assumptions, and dependencies 7. The whole blueprint and what makes a spec good 8. The next step 6. 2b - Requirement Language: Writing What the AI Executes Without Guessing 1. The Blueprint Is Right, the Handwriting Is Not 2. Where Specifications Come From 3. Before Anything: Functional or Technical 4. EARS: The Syntax That Will Not Let the Condition Stay Implicit 5. Given/When/Then: Behavior as a Scene 6. Design by Contract: What Holds Before, After and Always 7. ATDD: The Acceptance Criterion Written First 8. Which to Use, and When 9. What a Badly Formed Sentence Costs an Agent 7. 2c - The Scope of a Spec: How Much Fits in One Specification 1. The Question That Comes Before Writing 2. The Criterion: A Spec Is What Fits in One Lap 3. Completing and Reopening Fit Together; Creating and Deleting Do Not 4. When the Feature Is Too Big 5. When the Method Does Not Pay Off 6. What You Take From Here 8. 3 - Hands on: the SDD tools 1. From the blueprint to the wall 2. Three ways of doing the same thing 3. The cycle is the same, the incarnation changes 4. The honest comparison 5. The choice and why 6. Lean setup and first contact 7. The bridge to the full cycle 9. 4 - speckit constitution: the rules before the first move 1. The rules before the first move 2. What a project constitution is 3. What goes in and what stays out 4. Running the constitution step on the To-Do 5. The To-Do's constitution, principle by principle 6. Why the stack stays out 7. Living artifact and the bridge to the first spec 0. 4.5 - Appendix: the To-Do constitution 11. To-Do Constitution 1. Core Principles 2. Engineering Standards 3. Workflow 4. Governance 2. 5 - The complete SDD cycle 1. Before the first specify , a map 2. What you're learning is the cycle, not the app 3. The feature lives on a branch: main → branch → merge 4. The map in a single figure 5. The constitution sits above the loop 6. The loop, step by step 7. The artifacts talk to each other; that's why you clear the context 8. The map is drawn: the bridge to Ch. 6 13. 6 - Create and list tasks: the first complete loop 1. From the map to the ground: the first feature 2. One feature at a time: the backlog 3. Spotlight: specify in action 4. The anatomy from Ch. 2, actually filled in 5. What is spec and what is plan : the boundary 6. The rest of the loop, at a follow-along pace 7. Commit, merge, and the bridge to Ch. 7 4. 6.5 - Creating and listing tasks in practice: the whole loop, file by file 1. How to read this chapter 2. The input: the /speckit-specify prompt 3. What specify and clarify returned: spec.md 4. The requirements check: checklists/requirements.md 5. What plan decided: plan.md 6. The plan 's design artifacts 7. The execution list from tasks : tasks.md 8. The code implement generated 9. The portrait of the lap 15. 6b - Specification Anti-Patterns: Six Ways to Get It Wrong, Over and Over 1. Six Defects, All Taken From This App 2. 1. A Rule Inherited by Reference 3. 2. Initial State Left Undeclared 4. 3. A Verb With Two Owners 5. 4. A Repeated Edge With No Answer 6. 5. Scope That Grows Out of Convenience 7. 6. Fixing at the End of the Chain 8. The Checklist, in Six Questions 6. 7 - Completing a Task: When the Obvious Hides Decisions 1. The state of git, again 2. The feature of the moment, and specify at a light pace 3. "Completing" seems obvious. It is not. 4. The answers go back into the spec 5. What changes down the line 6. How to distrust the obvious 7. End of the loop and the bridge to Ch. 8 17. 7.5 - Completing and Reopening a Task in Practice: the Whole Loop, File by File 1. How to read this chapter 2. The input: the /speckit-specify prompt 3. What specify and clarify returned: spec.md 4. What plan decided: plan.md 5. The plan 's state model: data-model.md 6. The tasks execution list: tasks.md 7. The code implement generated 8. The portrait of the lap 8. 8 - Filtering Tasks: The Spotlight on plan and checklist 1. The third loop starts on main 2. specify and clarify , at a light pace 3. The what is already decided; the how is missing 4. Spotlight: plan decides the how 5. The constitution check has teeth 6. Spotlight: checklist as a quality gate 7. Closing the loop, at a light pace 8. The bridge to Ch. 9 9. 8.5 - Filtering Tasks in Practice: the Whole Loop, File by File 1. How to read this chapter 2. The input: the /speckit-specify prompt 3. What specify and clarify returned: spec.md 4. The requirements review: checklists/requirements.md 5. What plan decided: plan.md 6. The plan 's view model: data-model.md 7. The tasks execution list: tasks.md 8. The code implement generated 9. The portrait of the lap 0. 9 - Deleting a Task: The Spotlight on tasks and analyze 1. The fourth loop starts: 004-excluir-tarefa 2. The early steps, at a light pace 3. tasks : the plan turns into a list of steps 4. Why this order: TDD and layers 5. analyze : reading the three artifacts together 6. A real conflict: the deletion against "completing" 7. Fix at the source, and the cascade it triggers 8. From the branch to the merge, and the bridge to Ch. 10 21. 9.5 - Deleting a Task in Practice: the Whole Loop, File by File 1. How to Read This Chapter 2. The Input: the /speckit-specify Prompt 3. What specify and clarify Returned: spec.md 4. The Completeness Check: checklists/requirements.md 5. What plan Decided: plan.md 6. The analyze Report: analyze-report.md 7. The plan 's Model of the Operation: data-model.md 8. The tasks Execution List: tasks.md 9. The Code implement Generated 10. The Portrait of the Lap 2. 10 - Edit Task: The Spotlight on implement 1. The Last Loop Starts on main 2. From specify to analyze , at a Light Pace 3. implement Reads the Artifacts, Not the Chat 4. Red, Green, Refactor 5. Reviewing What the Agent Wrote 6. Loop Closed, App Complete 3. 10.5 - Editing a Task in Practice: the Whole Loop, File by File 1. How to Read This Chapter 2. The Input: the /speckit-specify Prompt 3. What specify and clarify Returned: spec.md 4. The Completeness Check: checklists/requirements.md 5. What plan Decided: plan.md 6. The analyze Report: analyze-report.md 7. The plan 's Model of the Operation: data-model.md 8. The tasks Execution List: tasks.md 9. The Code implement Generated 10. The Second Iteration, in the Order It Happened 11. The Portrait of the Lap, and of the Five 4. 10b - Iterative Refinement: The Spec After It Already Exists 1. No Document Is Born Finished 2. Four Doors the Change Comes Through 3. The Chain, in the Order Things Move 4. What Changes and What Does Not 5. When the Spec Stops Being Trustworthy 6. The Document That Outlives the Project 5. 11 - The Whole App Was Born From Five Loops 1. Stop and Look Back 2. The Whole App Is Five Merges Into main 3. The Timeline in One Figure 4. Each Feature Lit a Spotlight 5. Together, They Covered the Whole Cycle 6. One Constitution Governed the Five Loops 7. The Cycle Is Yours Now 8. What If I Did This Without SDD? 9. The To-Do Was the Vehicle; the Process Was the Protagonist 6. Canonical Glossary 1. Terms 2. Rules