implement-feature

implement-feature is a skill for Claude Code from arozumenko/sdlc-skills. It costs 54 tokens per session (884 once invoked), scanned A, original, MIT.

A workflow for delivering a software feature from an approved plan through testing, implementation, verification, and release. TDD, or test-driven development, means writing tests for the expected behavior before the implementation.

In plain words
What is it for?
Use it to load acceptance criteria, write tests, build the feature, run manual and automated checks, commit the work, open a pull request, and document progress on the issue.
Why use it?
It makes the definition of done explicit and checks the work at several stages. This helps catch unclear requirements, missing tests, and integration problems before release.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions subagents.

Part of the sdlc-skills plugin — 53 skills shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/arozumenko/sdlc-skills/implement-feature
Any agent
npx skills add arozumenko/sdlc-skills --skill implement-feature
Clone the repo
git clone --depth 1 https://github.com/arozumenko/sdlc-skills

Made for: Claude Code.

Or install sdlc-skills, the plugin that ships this one along with the rest of its 53 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for implement-feature

README.md
[![agentmods](https://agentmods.dev/badge/skills/arozumenko/sdlc-skills/implement-feature.svg)](https://agentmods.dev/skills/arozumenko/sdlc-skills/implement-feature)
Your own site
<a href="https://agentmods.dev/skills/arozumenko/sdlc-skills/implement-feature"><img src="https://agentmods.dev/badge/skills/arozumenko/sdlc-skills/implement-feature.svg" alt="Measured on agentmods" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 884 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00054 $0.00884
Opus 5 $0.00027 $0.00442
Sonnet 5 $0.00011 $0.00177
Haiku 4.5 $0.00005 $0.00088

Measured 6d ago against content hash 93469abefefc, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

implement-feature scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

Sanity check before running automated tests. API → `curl` the endpoint. UI →
bundles/feature-development/skills/implement-feature/SKILL.md · 102 lines

How it starts

The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Feature Implementation: Plan → Test → Build → Verify → Ship

Core philosophy: understand the plan, write tests first, implement to pass them, verify everything, ship clean.

Platform & systems

gh issue … / gh pr … below are the GitHub reference. Translate to your tracker per .agents/profile.md § Project systems (jira / gitlab-issues / azure-boards / linear) and your code host's CLI per .agents/workflow.md (GitLab glab, Azure DevOps az repos, Bitbucket bb, Gitea tea). If scout hasn't recorded them, ask before assuming GitHub.

The eight steps

1. Load the plan
2. Write test cases
3. Implement
4. Manual verification
5. Write automated tests
6. Run full test suite
7. Commit & PR
8. Document on ticket

1. Load the plan

gh issue view <N>. Identify acceptance criteria (definition of done), interface contract (input/output types if defined), dependencies, and what's explicitly in and out of scope. If anything is unclear, ask the tech-lead via a subagent call or tracker comment before writing code. Post a 🔧 **Started** comment so the team knows work is in progress.

2. Write test cases (TDD red phase)

Define "done" as executable tests before implementing. For each acceptance criterion, write a test. Cover happy path, error cases, edge cases. Run them and confirm they fail — that's the red phase.

3. Implement

Write the minimum code to pass the tests. Rules:

  • Follow existing patterns — read similar features in the codebase first
  • One change at a time — verify syntax after each file edit
  • Match the interface contract exactly if the task defines one
  • No scope creep — don't add features beyond the acceptance criteria
  • Don't refactor neighbors — a feature task is not a cleanup task
  • Don't optimize prematurely — make it work before making it fast

4. Manual verification

Sanity check before running automated tests. API → curl the endpoint. UI → browser snapshot + interaction. Backend logic → one-liner that calls the function. Catches the obvious breaks before test run.

Read the full file on GitHub · 102 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 6d ago First seen · 102 lines · 54 tokens per session scan A 93469abefefc

Subscribe to this mod's changes

implement-feature is a skill published in the GitHub repository arozumenko/sdlc-skills (20 stars, last pushed yesterday), licensed MIT. It adds 54 tokens to every session and 884 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.