sdd-implement

name	sdd-implement
description	Implement features by working through tasks.md step by step with TDD. Reads the full spec (requirements.md, design.md, tasks.md), implements each task in order, and updates progress. Works in both Claude Code and Cursor.

sdd-implement

Purpose

Execute the implementation phase of SDD by following tasks.md systematically. Ensures each task is implemented with TDD discipline and spec compliance.

When to Use

• After spec is complete (requirements.md + design.md + tasks.md finalized)
• To resume implementation of a partially completed spec
• When picking up implementation from a handoff report

Arguments

• $ARGUMENTS: Spec ID (e.g., KNOW-001) or path to spec directory

Step-by-Step Instructions

1. Load Context

1. Read the full spec:

   • specs/KNOW-{NNN}-*/requirements.md — acceptance criteria
   • specs/KNOW-{NNN}-*/design.md — architecture, interfaces
   • specs/KNOW-{NNN}-*/tasks.md — ordered task list

2. Check current progress: which tasks are already checked off?

3. If there's a handoff report, read it for additional context

2. For Each Unchecked Task

Execute the TDD cycle:

Red (Write failing test):

1. Read the task description and the relevant design.md section
2. Write a test that expresses the expected behavior
3. Run: pnpm test:run → confirm test FAILS

Green (Make it pass):

1. Write minimal code following design.md interfaces
2. Run: pnpm test:run → confirm test PASSES
3. Don't over-engineer; just satisfy the test

Refactor:

1. Clean up the implementation (if needed)
2. Run: pnpm verify → confirm everything still passes

Update Progress:

1. Check off the task in tasks.md: - [x] Task N
2. If the task was the last in a phase, run pnpm verify as a checkpoint

3. Handle Deviations

If during implementation you discover:

• Missing task: Add it to tasks.md before implementing
• Design needs change: Update design.md first, then implement
• Requirement unclear: Check requirements.md; if still unclear, ask the user
• Spec is wrong: Update the spec, then implement the correct version

4. Complete Implementation

After all tasks are checked off:

1. Run pnpm verify one final time
2. Run pnpm test:coverage to check coverage target (80%)
3. Update spec status to review in requirements.md
4. Create PR against develop with spec reference in description

Best Practices

• Never skip a task or implement out of order
• Commit after each task (atomic commits, Conventional Commits)
• If you get stuck, check knowledgine-recall for similar past work
• Record learnings with knowledgine-capture as you go

Reference Files

• docs/workflows/phase2-implementation.md — Detailed implementation guidance
• AGENTS.md — Code standards to follow
• CONTRIBUTING.md — Full coding standards reference