implement

A workflow for implementing one clearly bounded software change from an approved plan, task, specification, or direct request.

In plain words
What is it for?
Use it to build or fix a defined outcome, update task progress, inspect affected tests, make the required code changes, and run suitable validation.
Why use it?
It keeps edits small, checks dependencies and existing code first, and leaves the repository in a verifiable state. It stops when a decision is still unclear instead of guessing.

Skill for Claude CodeCodex

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/rmjosea/agentic-sdlc-kit/implement
Any agent
npx skills add rmjosea/agentic-sdlc-kit --skill implement
Clone the repo
git clone --depth 1 https://github.com/rmjosea/agentic-sdlc-kit

Made for: Claude Code, Codex.

Per session 72 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 891 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 $0.00072 $0.00891
Opus 5 $0.00036 $0.00445
Sonnet 5 $0.00014 $0.00178
Haiku 4.5 $0.00007 $0.00089

Measured 2d ago against content hash 2b6f2c818254, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

implement 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 2d 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.

.agents/skills/implement/SKILL.md · 83 lines

How it starts

The opening of the file, as written. The whole thing — 83 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Implement a Bounded Change

Complete one bounded outcome at a time and leave the repository in a verifiable state.

Select and bound

  1. Read AGENTS.md, the selected source artifacts, and only required contracts.
  2. Select exactly one valid input:
    • a ready task from tasks.md: re-read task state, confirm every dependency is done, then transition it to in-progress;
    • one bounded, decision-complete outcome from an approved spec or plan that does not require a task graph: state the selected outcome and artifact evidence;
    • a direct-path change: confirm every direct-path condition in AGENTS.md and state Intent, Change, and Verification inline.
  3. Inspect the affected code and tests before editing.
  4. State the outcome, intended change surface, and validation.
  5. Stop for a material ambiguity; do not invent product or architecture choices.

If execution changes how, update the durable plan or inline approach. When a design change affects task boundaries, dependencies, validation, or change surfaces, mark affected tasks stale and run decompose-tasks again before continuing. If execution changes what, stop and reconfirm the accepted intent; amend a spec when one exists or the expanded scope requires one. Mark affected durable work stale.

Execute

  • Make the smallest coherent change that satisfies the task.
  • Follow existing repository conventions before introducing new patterns.
  • Avoid unrelated cleanup and speculative abstraction.
  • Work in short edit-run-observe loops.
  • Preserve compatibility unless the approved plan says otherwise.
  • Treat external input, secrets, permissions, and destructive effects as trust boundaries.

Read references/testing.md when selecting or writing tests. Read references/debugging.md only when a failure is not explained by the current change.

Verify

Run the narrowest useful checks during iteration, then all outcome-relevant checks before completion. Compare observed behavior with authoritative intent and the applicable artifact or inline evidence.

Read the full file on GitHub · 83 lines

Files

What ships with it

3 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. 2d ago First seen · 83 lines · 72 tokens per session scan A 2b6f2c818254

Subscribe to this mod's changes

implement is a skill published in the GitHub repository rmjosea/agentic-sdlc-kit (2 stars, last pushed 1mo ago), licensed MIT. It adds 72 tokens to every session and 891 once invoked, about $0.0004 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 2026-08-31.

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