check-portability

check-portability is a skill for Claude Code, Codex from leifericf/agentic-sdk. It costs 33 tokens per session (909 once invoked), scanned A, original, MIT.

A code-review checklist for platform differences, such as operating systems, byte order, file paths, file locking, and integer sizes. Portability means that software behaves correctly on every platform the project supports.

In plain words
What is it for?
Use it to inspect native and platform-specific code, filesystem handling, event watchers, platform checks, and assumptions about data representation.
Why use it?
Code can work on the developer's computer while failing elsewhere when operating-system or hardware assumptions are hidden in it.

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/leifericf/agentic-sdk/check-portability
Any agent
npx skills add leifericf/agentic-sdk --skill check-portability
Clone the repo
git clone --depth 1 https://github.com/leifericf/agentic-sdk

Made for: Claude Code, Codex.

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 check-portability

README.md
[![agentmods](https://agentmods.dev/badge/skills/leifericf/agentic-sdk/check-portability.svg)](https://agentmods.dev/skills/leifericf/agentic-sdk/check-portability)
Your own site
<a href="https://agentmods.dev/skills/leifericf/agentic-sdk/check-portability"><img src="https://agentmods.dev/badge/skills/leifericf/agentic-sdk/check-portability.svg" alt="Measured on agentmods" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 909 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 $0.00033 $0.00909
Opus 5 $0.00016 $0.00454
Sonnet 5 $0.00007 $0.00182
Haiku 4.5 $0.00003 $0.00091

Measured 5d ago against content hash 1f608dacf446, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

check-portability 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.

skills/check-portability/SKILL.md · 96 lines

How it starts

The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.

check-portability

Role: review the shard for behavior that works on one platform but breaks on another.

Failure model: the code runs on the development platform and silently misbehaves on a committed platform, because a platform difference was not gated or a host-order assumption leaked.

Read the design docs for the project's platform commitments before sweeping. A platform the project does not commit to is out of scope.

Look for

  1. Platform branches not compile-time gated. A platform check that runs at runtime when it could fold away at compile time; a platform path that ships in a release build for a platform it does not target; a check that tests the wrong platform predicate.
  2. Filesystem semantics that differ. Case sensitivity, path separators, max path length, reserved names, mandatory versus advisory file locking, atomic-rename guarantees, permission models. Use the platform library's path handling; do not hand-roll. A path built with a hardcoded separator or a hardcoded home directory is a finding.
  3. Watcher and event-source divergence. When the project watches the filesystem or subscribes to OS events, the shape of the event differs across platforms (rename versus modify coalescing, latency guarantees, recursive defaults). A body that assumes one platform's semantics and breaks on the other is a finding.
  4. Surface and windowing creation. Graphics or window surface creation is platform-specific. The surface code must gate the right path per platform. A call to the wrong platform's surface creator is a build failure, not a finding; an unused but compiled surface path that pulls the wrong system framework is.
  5. System-library availability. A decoder or integration that uses a system library on one platform and a bundled library on another. The dispatch must be platform-aware; a path that assumes the system library will not work where it is absent.
  6. Endianness and integer widths. External formats (file headers, wire protocols, serialized state) have specific byte orders; a host-order reinterpret is a finding. Pointer widths and the C fixed-width types (c_int, c_long, long) differ across platforms; a type whose width varies, used in a persistence or wire shape, is a finding. Use fixed-width types at every external boundary.
  7. Baked artifact portability. A build that produces a platform- specific artifact (a dylib, a shared object, an executable) must target every platform the project commits to, and the runtime must select the right one for the host. A bake that produces one platform only and tries to load it on another is a build-config finding.

Read the full file on GitHub · 96 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. 5d ago First seen · 96 lines · 33 tokens per session scan A 1f608dacf446

Subscribe to this mod's changes

check-portability is a skill published in the GitHub repository leifericf/agentic-sdk (5 stars, last pushed 3d ago), licensed MIT. It adds 33 tokens to every session and 909 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 2026-08-31.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

local-ai-agents

Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…

microsoft/ai-agents-for-beginners · 200 tokens

chronicle

Analyze Copilot session history for standup reports, usage tips, session search, and session reindexing. Use when the user asks for a standup, daily summary, usage tips, workflow recommendations, wants to search or find past sessions by keyword/file/PR, wants to reindex their session store, or asks about deleting…

microsoft/vscode · 72 tokens

imagegen

Generate or edit raster images when the task benefits from AI-created bitmap visuals such as photos, illustrations, textures, sprites, mockups, or transparent-background cutouts. Use when Codex should create a brand-new image, transform an existing image, or derive visual variants from references, and the output…

openai/codex · 113 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens