implementation-approach

A decision process for choosing the smallest implementation that meets the current requirements and can be checked against repository evidence.

In plain words
What is it for?
Use it to select an implementation strategy, evaluate risks, and define the right amount of verification for a coding task.
Why use it?
It reduces unnecessary code, dependencies, testing, and maintenance by adding complexity only when the simpler approach fails.

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/shinpr/agentic-code/implementation-approach
Any agent
npx skills add shinpr/agentic-code --skill implementation-approach
Clone the repo
git clone --depth 1 https://github.com/shinpr/agentic-code

Made for: Claude Code, Codex.

Per session 22 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 542 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 $0.00022 $0.00542
Opus 5 $0.00011 $0.00271
Sonnet 5 $0.00004 $0.00108
Haiku 4.5 $0.00002 $0.00054

Measured 2d ago against content hash f4e88ce2807d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

implementation-approach 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/implementation-approach/SKILL.md · 48 lines

How it starts

The opening of the file, as written. The whole thing — 48 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Implementation Approach

Strategy Selection

Use this sequence when a design or task needs an implementation approach:

  1. Current evidence: Inspect the relevant responsibility, data or control path, representative repository pattern, and constraints that can change the choice.
  2. Direct implementation: Describe the simplest end-to-end change that delivers the confirmed outcome through the existing architecture and dependencies.
  3. Failure check: Test the direct implementation against current requirements, verified constraints, observed problems, and evidence-backed material risks within scope.
  4. Targeted expansion: Add only what resolves a failed item. Compare the smaller design with and without the addition.
  5. Value and subtraction check: Retain an addition only when evidence shows that its outcome benefit justifies its implementation, testing, documentation, runtime, and maintenance cost.

Possible future reuse, generic best practice, speculative edge cases, and optional hardening are not failed items. File count is supporting evidence, not a strategy rule.

Keep unselected candidates in the active execution context. Create a durable artifact only for a named downstream consumer.

Slicing Choice

Choose the smallest structure that preserves real dependency order and yields observable progress:

  • Vertical: One user- or consumer-visible outcome can be completed across its layers without first creating a shared foundation.
  • Foundation-first: Multiple required outcomes depend on the same contract or mechanism that must exist before any can work.
  • Hybrid: One verified shared dependency comes first, followed by outcome-oriented slices.

Create phases from verified dependencies rather than architecture layers. Keep independently executable work separate when combining it would obscure ownership or verification.

Verification Level

Select the narrowest level that exercises the boundary named by the requirement:

  • L1: Local: A unit, pure transformation, local command, build, or artifact check.
  • L2: Integration: Interaction across components, persistence, processes, or another named integration boundary.
  • L3: End-to-end: The complete user, browser, process, or service journey required by the acceptance criterion.

Read the full file on GitHub · 48 lines

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 · 48 lines · 22 tokens per session scan A f4e88ce2807d

Subscribe to this mod's changes

implementation-approach is a skill published in the GitHub repository shinpr/agentic-code (49 stars, last pushed 3d ago), licensed MIT. It adds 22 tokens to every session and 542 once invoked, about $0.0001 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.