validate-api

validate-api is a skill for Claude Code, Codex from johnkozaris/jko-claude-plugins. It costs 20 tokens per session (243 once invoked), scanned A, original, MIT.

A test runner for Hurl scenarios, which are scripted checks that send requests to a web API and verify its responses. It obtains a development OIDC access token when needed; OIDC is a standard way for an application to prove a user's identity.

In plain words
What is it for?
Run selected or discovered Hurl API tests against a configured backend, using the project's existing health checks and token setup. It helps identify whether a failure comes from the backend, test data, token, environment, or test itself.
Why use it?
It removes the manual work of finding API checks, getting a login token, choosing the right server, and interpreting failures. It also asks for confirmation before contacting production.

Skill for Claude CodeCodex

Part of the backend-validator plugin — 3 skills shipped together

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/johnkozaris/jko-claude-plugins/validate-api
Any agent
npx skills add johnkozaris/jko-claude-plugins --skill validate-api
Clone the repo
git clone --depth 1 https://github.com/johnkozaris/jko-claude-plugins

Made for: Claude Code, Codex.

Or install backend-validator, the plugin that ships this one along with the rest of its 3 skills.

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 validate-api

README.md
[![agentmods](https://agentmods.dev/badge/skills/johnkozaris/jko-claude-plugins/validate-api.svg)](https://agentmods.dev/skills/johnkozaris/jko-claude-plugins/validate-api)
Your own site
<a href="https://agentmods.dev/skills/johnkozaris/jko-claude-plugins/validate-api"><img src="https://agentmods.dev/badge/skills/johnkozaris/jko-claude-plugins/validate-api.svg" alt="Measured on agentmods" height="20"></a>
Per session 20 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 243 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 $0.00020 $0.00243
Opus 5 $0.00010 $0.00121
Sonnet 5 $0.00004 $0.00049
Haiku 4.5 $0.00002 $0.00024

Measured 4d ago against content hash cb5aab225666, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

validate-api 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 4d 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.

plugins/backend-validator/skills/validate-api/SKILL.md · 34 lines

What it actually says

Validate API

Use $ARGUMENTS or discover the project's Hurl scenarios. Resolve API_BASE_URL from project configuration. Confirm before contacting production.

Use $TOKEN when present. Otherwise run ${TOKEN_COMMAND:-scripts/get-backend-token.sh}; if that command is absent, route through /backend-validator:get-dev-token.

Confirm the backend is reachable using a project-defined readiness or health surface when one exists. Do not invent an endpoint.

Run the target with the installed Hurl secret-variable interface:

hurl --test \
  --secret token="$TOKEN" \
  --variable base_url="$API_BASE_URL" \
  "$TARGET"

On failure, identify the exact scenario/assertion and distinguish backend, fixture, token, environment, and test defects.

Use the project's existing validation stack rather than replacing it. Load references/hurl-patterns.md for captures, retries, parallel isolation, and report-leakage details.

Files

What ships with it

1 file 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. 4d ago First seen · 34 lines · 20 tokens per session scan A cb5aab225666

Subscribe to this mod's changes

validate-api is a skill published in the GitHub repository johnkozaris/jko-claude-plugins (11 stars, last pushed 7d ago), licensed MIT. It adds 20 tokens to every session and 243 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.

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