Implementation

Implementation is a skill for Claude Code, Codex from rsts-dev/claude-buddy-marketplace. It costs 47 tokens per session (486 once invoked), scanned A, original, MIT.

An implementation workflow that turns task documents into code in planned phases. TDD, or test-driven development, means writing a failing test before writing the code that makes it pass.

In plain words
What is it for?
Use it to discover tasks in a specs folder, write and run tests, build the core feature, integrate it, polish it, and update task checkboxes. It requires a LifeOS installation, a foundation file, and task documents.
Why use it?
It breaks implementation into trackable stages and checks each task as work progresses. It also stops after sequential failures instead of silently continuing with a broken result.

Skill for Claude CodeCodex

Part of the buddy plugin — 7 skills, 7 commands 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/rsts-dev/claude-buddy-marketplace/implementation
Any agent
npx skills add rsts-dev/claude-buddy-marketplace --skill implementation
Clone the repo
git clone --depth 1 https://github.com/rsts-dev/claude-buddy-marketplace

Made for: Claude Code, Codex.

Or install buddy, the plugin that ships this one along with the rest of its 7 skills, 7 commands.

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 Implementation

README.md
[![agentmods](https://agentmods.dev/badge/skills/rsts-dev/claude-buddy-marketplace/implementation.svg)](https://agentmods.dev/skills/rsts-dev/claude-buddy-marketplace/implementation)
Your own site
<a href="https://agentmods.dev/skills/rsts-dev/claude-buddy-marketplace/implementation"><img src="https://agentmods.dev/badge/skills/rsts-dev/claude-buddy-marketplace/implementation.svg" alt="Measured on agentmods" height="20"></a>
Per session 47 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 486 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. 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 $0.00047 $0.00486
Opus 5 $0.00023 $0.00243
Sonnet 5 $0.00009 $0.00097
Haiku 4.5 $0.00005 $0.00049

Measured 5d ago against content hash e8c356e442ed, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

Implementation scanned grade A with 0 findings 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 5d 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

plugins/buddy/skills/Implementation/SKILL.md · 58 lines

What it actually says

Implementation

Execute tasks from tasks.md following TDD workflow with phase-by-phase execution, progress tracking, and completion validation.

Customization

Before executing, check for user customizations at: ~/.claude/LIFEOS/USER/CUSTOMIZATIONS/SKILLS/Implementation/

If this directory exists, load and apply any PREFERENCES.md configurations. If not, proceed with defaults.

Prerequisites

  1. LifeOS must be installed. Check ~/.claude/LIFEOS/VERSION.
  2. Foundation must exist at /directive/foundation.md.
  3. Tasks must exist in specs/ directory.

Workflow Routing

Workflow Trigger File
ExecuteTasks Any invocation Workflows/ExecuteTasks.md

Task Discovery

Scans specs/ for folders containing tasks.md. If multiple found, asks user which to execute.

Execution Model

  • Phase-by-phase: Setup -> Tests (TDD) -> Core -> Integration -> Polish
  • TDD: Tests MUST fail first (red), then pass after implementation (green)
  • Progress: Updates checkboxes in tasks.md after each completed task
  • Errors: Halts on sequential task failure; continues on parallel [P] failure

Output

Updates tasks.md in-place with completion checkboxes. Changes status to "Completed" when done.

Examples

Example 1: Execute implementation

User: "/buddy:implement"
-> Discovers specs/20260402-user-authentication/tasks.md
-> Reads all design documents (spec, plan, tasks, data-model, etc.)
-> Executes Phase 3.1 Setup tasks
-> Executes Phase 3.2 Tests (expects failures - TDD red)
-> Executes Phase 3.3 Core (tests should pass - TDD green)
-> Executes Phase 3.4 Integration, Phase 3.5 Polish
-> Updates tasks.md checkboxes throughout
-> Reports completion summary
Files

What ships with it

1 file 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. 5d ago First seen · 58 lines · 47 tokens per session scan A e8c356e442ed

Subscribe to this mod's changes

Implementation is a skill published in the GitHub repository rsts-dev/claude-buddy-marketplace (17 stars, last pushed 14d ago), licensed MIT. It adds 47 tokens to every session and 486 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.