openapi-lint

An OpenAPI checking skill for API specifications. OpenAPI is a standard format for describing an API's operations, inputs, and responses.

In plain words
What is it for?
Checking schemas, component definitions, and operation IDs in an OpenAPI document.
Why use it?
It catches missing data definitions and naming that is inconsistent across the specification.

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/tarekkharsa/agentstack/openapi-lint
Any agent
npx skills add Tarekkharsa/agentstack --skill openapi-lint
Clone the repo
git clone --depth 1 https://github.com/Tarekkharsa/agentstack

Made for: Claude Code, Codex.

Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 36 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 $0.00017 $0.00036
Opus 5 $0.00009 $0.00018
Sonnet 5 $0.00003 $0.00007
Haiku 4.5 $0.00002 $0.00004

Measured 2d ago against content hash 26317a4b7af5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

openapi-lint 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.

examples/sandbox/projects/api-service/skills/openapi-lint/SKILL.md · 9 lines

What it actually says

openapi-lint

Validate components and operationIds.

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 · 9 lines · 17 tokens per session scan A 26317a4b7af5

Subscribe to this mod's changes

openapi-lint is a skill published in the GitHub repository Tarekkharsa/agentstack (3 stars, last pushed 19d ago), licensed Apache-2.0. It adds 17 tokens to every session and 36 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 2026-08-31.