api-spectral

A linter and security checker for API description files, using Stoplight Spectral. It checks OpenAPI, AsyncAPI, and Arazzo specifications against defined rules.

In plain words
What is it for?
Validating API specifications against security best practices, the OWASP API Security Top 10, and custom organisational rules.
Why use it?
It can catch unclear, unsafe, or non-standard API definitions before they are used to build or publish an API. Teams can apply both security guidance and their own standards.

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/agentsecops/secopsagentkit/api-spectral
Any agent
npx skills add AgentSecOps/SecOpsAgentKit --skill api-spectral
Clone the repo
git clone --depth 1 https://github.com/AgentSecOps/SecOpsAgentKit

Made for: Claude Code, Codex.

Per session 138 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,267 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00138 $0.05267
Opus 5 $0.00069 $0.02634
Sonnet 5 $0.00028 $0.01053
Haiku 4.5 $0.00014 $0.00527

Measured yesterday against content hash 52f043e774ab, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

api-spectral 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 yesterday.

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/appsec/api-spectral/SKILL.md · 709 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

9 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. yesterday First seen · 709 lines · 138 tokens per session scan A 52f043e774ab

Subscribe to this mod's changes

api-spectral is a skill published in the GitHub repository AgentSecOps/SecOpsAgentKit (201 stars, last pushed 4mo ago), with no licence file. It adds 138 tokens to every session and 5,267 once invoked, about $0.0007 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.

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